Shoulder Pain Traumatic PCAs

Shoulder Pain Traumatic PCAs. CT Arthrography Shoulder CT Arthrography Shoulder CT arthrography has shown fair agreement between observers and is comparable to MR arthrography in diagnosing Bankart and Hill-Sachs lesions [12,13]. However, CT arthrography is inferior to MRI in diagnosing other soft-tissue pathology [12]. CT arthrography can be considered a reasonable imaging alternative in patients with contraindication to MRI.


Shoulder Pain Traumatic PCAs

Shoulder Pain Traumatic PCAs. US Shoulder US Shoulder There is no role for US in assessment of Bankart or Hill-Sachs lesions. US has been demonstrated to be inferior to MRI in diagnosing both labroligamentous injury and Hill-Sachs lesions [17].


Shoulder Pain Traumatic PCAs

Shoulder Pain Traumatic PCAs. FDG-PET/CT Skull Base to Mid-Thigh There is no role for FDG-PET/CT in assessment of Bankart or Hill-Sachs lesions.


Shoulder Pain Traumatic PCAs

Shoulder Pain Traumatic PCAs. Bone Scan Shoulder Bone Scan Shoulder There is no role for bone scintigraphy in assessment of Bankart or Hill-Sachs lesions.


Shoulder Pain Traumatic PCAs

Shoulder Pain Traumatic PCAs. Variant 6: Traumatic shoulder pain. Radiographs normal. Physical examination and history consistent with dislocation event or instability. Next imaging study. Shoulder dislocation or instability is most common in the anterior direction. Younger patients are more likely to have labroligamentous injury and persistent instability after dislocation compared with older patients [54]. Older patients are more likely to have rotator cuff tears in association with shoulder dislocation [55]. Coexisting humeral avulsion of the glenohumeral ligament and significant glenoid bone loss have been found in up to 10% of patients with recurrent shoulder instability [56], which underscores the need to assess both osseous and labroligamentous pathology in patients with shoulder dislocation or instability. Glenoid morphology and bone loss can play a significant factor in recurrent shoulder dislocations [15,16,57], which may require bone grafting in order to restore stability [57].


Shoulder Pain Traumatic PCAs

Shoulder Pain Traumatic PCAs. MR Arthrography Shoulder MR arthrography is the preferred examination for the evaluation of subacute shoulder dislocations or recurrent shoulder instability. MRI has been shown to have similar performance to CT in the evaluation of Hill-Sachs lesions and glenoid bone loss [12,18]. MR arthrography has also been found to be reliable in diagnosing anterior shoulder instability and labroligamentous injuries [58,59]. MR arthrography has specifically outperformed noncontrast MRI in assessment of glenohumeral ligament and anterior labral injuries [17,19], which are commonly seen in shoulder instability. MR arthrography has also outperformed noncontrast MRI in diagnosis of rotator cuff tears [17,19], which is a common associated finding in older patients with shoulder dislocation. However, high sensitivities reported for MR arthrography in the detection of labral pathology may not be applicable to patients with clinically unstable shoulders. A retrospective review of 90 patients with clinically unstable shoulders selected for arthroscopy [60] found that MR arthrography had a sensitivity of 65% for detection of labral tears. The authors proposed that this discrepancy with prior studies was the result of different patient selection criteria (clinically unstable in their study versus less-specific symptoms such as shoulder pain in others) and the interpretation of MR arthrography by experienced musculoskeletal radiologists [60]. For this document, it is assumed the procedure is performed and interpreted by an expert.


Shoulder Pain Traumatic PCAs

Shoulder Pain Traumatic PCAs. MRI Shoulder MRI without contrast may be preferred to MR arthrography in the setting of acute shoulder dislocation when a post-traumatic joint effusion is present to provide sufficient visualization of soft-tissue structures. In the subacute or chronic setting, the glenohumeral joint effusion is usually too small to provide adequate joint distention for optimal assessment of soft-tissue structures. Noncontrast MRI has been shown to be inferior to MR arthrography in diagnosing labroligamentous and rotator cuff injuries [17,19]. Noncontrast MRI performs comparably to CT in evaluating glenoid and humeral head bone loss [12,18], which may obviate the need for noncontrast CT.


Shoulder Pain Traumatic PCAs

Shoulder Pain Traumatic PCAs. CT Arthrography Shoulder CT Arthrography Shoulder CT arthrography is effective in evaluation of shoulder instability. CT arthrography is comparable to MR arthrography in the diagnosis of Bankart and Hill-Sachs lesions [12], and moderate agreement has been found between readers for diagnosing anterior capsule laxity on CT arthrography. However, CT arthrography has been shown to be inferior to MR arthrography in assessing partial-thickness rotator cuff tears [12], which makes CT arthrography less desirable in older patients with dislocation/instability where rotator cuff tears are common. CT arthrography may be considered in a patient with shoulder dislocation/instability and contraindication to MRI.


Shoulder Pain Traumatic PCAs

Shoulder Pain Traumatic PCAs. CT Shoulder Noncontrast CT has historically been performed to assess bone loss in patients with recurrent dislocation or chronic instability. However, recent studies have shown MRI to be equivalent to CT in assessment of glenoid and humeral head bone loss [12,18], which places in question the need for noncontrast CT in the assessment of shoulder instability. Noncontrast CT is also unable to assess rotator cuff and labroligamentous pathology commonly seen in shoulder dislocations/instability. In general, CT should be reserved for patients with a contraindication to MRI or patients in whom MRI assessment of bone loss is limited.


Shoulder Pain Traumatic PCAs

Shoulder Pain Traumatic PCAs. US Shoulder There is no defined role for US in the assessment of shoulder dislocation or instability. There is a potential limited role for use of dynamic US in assessing Hill-Sachs lesion engagement [61]. However, this is not common practice, and US has been shown to be inferior to MRI in diagnosing the common structural abnormalities associated with shoulder instability, such as labroligamentous injuries, Hill-Sachs lesions, and partial rotator cuff tears [17].


Shoulder Pain Traumatic PCAs

Shoulder Pain Traumatic PCAs. FDG-PET/CT Skull Base to Mid-Thigh There is no role for FDG-PET/CT in assessment of shoulder instability.


Shoulder Pain Traumatic PCAs

Shoulder Pain Traumatic PCAs. Bone Scan Shoulder Bone Scan Shoulder There is no role for bone scintigraphy in assessment of shoulder instability.


Shoulder Pain Traumatic PCAs

Shoulder Pain Traumatic PCAs. Variant 7: Traumatic shoulder pain. Radiographs normal. Physical examination findings consistent with labral tear. Next imaging study. MR Arthrography Shoulder MR arthrography has been reported to have a high sensitivity for detection of labral injury, ranging from 86% to 100% [20,59,62-65]; however, the issue of selection bias is inherent in the design of many of these retrospective


Shoulder Pain Traumatic PCAs

Shoulder Pain Traumatic PCAs. MRI Shoulder MRI without contrast may be preferred to MR arthrography in the setting of acute shoulder dislocation when a post-traumatic joint effusion is typically present to provide sufficient visualization of soft-tissue structures. In the subacute or chronic setting, the glenohumeral joint effusion is usually too small to provide adequate joint distention to adequately assess soft-tissue structures. Noncontrast MRI has been shown to be inferior to MR arthrography in diagnosing labroligamentous and rotator cuff injuries [17,19].


Shoulder Pain Traumatic PCAs

Shoulder Pain Traumatic PCAs. CT Arthrography Shoulder CT arthrography provides comparable sensitivity and possibly improved specificity in detection of labral lesions compared to MR arthrography [12,67] and can provide improved visualization of the bones in cases of complex trauma. However, interobserver variability in reporting of labral lesions is low [13]. CT arthrography has also been shown to be inferior to MR arthrography in assessing partial-thickness rotator cuff tears [12], which makes CT arthrography less desirable in patients where rotator cuff tears may be suspected. However, CT arthrography may be considered in a patient with shoulder dislocation/instability and contraindication to MRI.


Shoulder Pain Traumatic PCAs

Shoulder Pain Traumatic PCAs. CT Shoulder CT Shoulder Noncontrast CT is unable to assess rotator cuff and labroligamentous pathology.


Shoulder Pain Traumatic PCAs

Shoulder Pain Traumatic PCAs. US Shoulder Although there have been efforts to use US in diagnosis of labral lesions, it currently has no defined role in this setting.


Shoulder Pain Traumatic PCAs

Shoulder Pain Traumatic PCAs. FDG-PET/CT Skull Base to Mid-Thigh There is no role for FDG-PET/CT in assessment of suspected labral tear.


Shoulder Pain Traumatic PCAs

Shoulder Pain Traumatic PCAs. Bone Scan Shoulder There is no role for bone scintigraphy in assessment of suspected labral tear.


Shoulder Pain Traumatic PCAs

Shoulder Pain Traumatic PCAs. Variant 8: Traumatic shoulder pain. Radiographs normal. Physical examination findings consistent with rotator cuff tear. Next imaging study. US, MRI, and MR arthrography have similarly high sensitivity and specificity in detection of full-thickness rotator cuff tears. US and MRI have somewhat lower sensitivity for detection of partial-thickness tears when compared to MR arthrography [68]. However, because full-thickness tears are the main decision point on pursuing surgical repair, institutional preference may be the driving force for the selection of imaging modality for assessment of traumatic rotator cuff pathology.


Shoulder Pain Traumatic PCAs

Shoulder Pain Traumatic PCAs. MRI Shoulder MRI Shoulder MRI is generally considered the best modality for adequately assessing most soft-tissue injuries, including labroligamentous, cartilage, and rotator cuff pathology [12,17,69]. It has high sensitivity and specificity in detection of full-thickness rotator cuff tears, but lower sensitivity compared to MR arthrography for detection of partial-thickness tears [68].


Shoulder Pain Traumatic PCAs

Shoulder Pain Traumatic PCAs. MR Arthrography Shoulder MR arthrography is generally preferred to noncontrast MRI for assessing intra-articular pathology, particularly in diagnosing labral and partial-thickness rotator cuff tears [17,19,54]. MR arthrography may have increased sensitivity for detection of partial-thickness articular surface supraspinatus tears compared with conventional MRI [19].


Shoulder Pain Traumatic PCAs

Shoulder Pain Traumatic PCAs. CT Arthrography Shoulder CT Arthrography Shoulder CT arthrography has similar performance as MR arthrography for detection of full-thickness rotator cuff tears, but has significantly poorer performance for partial-thickness cuff tears [12]. CT arthrogram may be a good imaging alternative in patients with suspected intra-articular soft-tissue injury and contraindication to MRI.


Shoulder Pain Traumatic PCAs

Shoulder Pain Traumatic PCAs. US Shoulder In the post-traumatic setting, US has been shown to detect abnormalities, including rotator cuff tears [25]. In general, US can have high sensitivity and specificity for the detection of full-thickness rotator cuff tears [70-72]. There is conflicting evidence on the ability of US to diagnose partial-thickness rotator cuff tears [17,22,24,44,72]. Similarly, although interobserver agreement in detection of full-thickness rotator cuff tears can be high, it is much more variable for detection of partial-thickness tears [73,74].


Shoulder Pain Traumatic PCAs

Shoulder Pain Traumatic PCAs. FDG-PET/CT Skull Base to Mid-Thigh FDG-PET/CT is not routinely used for describing rotator cuff tears. Indirect identification of symptomatic rotator cuff tears has been described on FDG-PET/CT by decreased radiotracer activity in the muscles of the torn tendons and increased activity of surrounding shoulder girdle muscles due to muscle recruitment [28,29]. However, FDG- PET/CT cannot describe the extent of rotator cuff tear or degree of rotator cuff atrophy, which are relevant for clinical management.


Shoulder Pain Traumatic PCAs

Shoulder Pain Traumatic PCAs. Bone Scan Shoulder Bone scintigraphy is not routinely used for describing rotator cuff tears. Increased radiotracer activity has been associated with symptomatic rotator cuff tears [33]. However, bone scintigraphy cannot describe the extent of rotator cuff tear or degree of rotator cuff atrophy, which are relevant for clinical management.


Shoulder Pain Traumatic PCAs

Shoulder Pain Traumatic PCAs. Variant 9: Traumatic shoulder pain. Radiographs already performed. Physical examination consistent with vascular compromise. Next imaging study. The subclavian, axillary, and brachial arteries are uncommonly injured following fractures and dislocations about the shoulder; however, the consequences can be debilitating. Of these, the axillary artery is more likely to be injured in patients with proximal humeral fractures, and the risk increases in the presence of open fractures, shoulder dislocation, and fractures of the scapula and ribs [75]. No systematic or comparative data is available on detection of arterial injuries in the post-traumatic setting.


Shoulder Pain Traumatic PCAs

Shoulder Pain Traumatic PCAs. CT Shoulder Noncontrast CT may be able to demonstrate hematomas; however, it is not an adequate modality for evaluation of acute arterial compromise. Contrast-enhanced CT using intravenous (IV) contrast can identify some vascular injuries. However, contrast bolus timing and image reformatting using routine contrast-enhanced CT protocols is suboptimal for identifying and characterizing vascular injuries.


Shoulder Pain Traumatic PCAs

Shoulder Pain Traumatic PCAs. CTA Shoulder CTA Shoulder CT angiography (CTA) is a specialized protocol for contrast-enhanced CT in which image acquisition occurs during maximum arterial opacification by IV contrast. Thin-slice axial images of the region of interest is performed, which helps in detection of subtle vascular injuries. Maximum intensity projection (MIP) images in multiple planes are also commonly performed, allowing for long segments of vessels to be visualized on a single image. CTA is the preferred examination for evaluation of suspected arterial injury. It can delineate the extent of injury and has the added benefit of providing optimal assessment of osseous injuries [76,77].


Shoulder Pain Traumatic PCAs

Shoulder Pain Traumatic PCAs. MRI Shoulder Because of the length of time required for MRI, it is not the modality of choice for assessment of acute arterial injury. Both routine noncontrast and contrast-enhanced MRI protocols lack the spatial and temporal resolution as well as imaging plane orientation to identify and characterize most arterial injuries.


Shoulder Pain Traumatic PCAs

Shoulder Pain Traumatic PCAs. MRA Shoulder MRA Shoulder MR angiography (MRA) is MR imaging tailored to evaluate for arterial compromise using sequences such as time-of-flight, phase-contrast, and dynamic postcontrast imaging. MRA can produce 2D images or dynamic 3D images of the arteries that simulates arteriography. However, the special resolution of MRA is inferior to CTA and arteriography. MRA can be performed with or without IV contrast, although use of IV contrast is generally preferred. Because of the length of time required for MRA, it is not the modality of choice for assessment of acute arterial injury.


Shoulder Pain Traumatic PCAs

Shoulder Pain Traumatic PCAs. US Duplex Doppler Shoulder Bedside US can be used to assess the subclavian, axillary, and brachial arteries as permitted by patient condition.


Shoulder Pain Traumatic PCAs

Shoulder Pain Traumatic PCAs. FDG-PET/CT Skull Base to Mid-Thigh There is no role for FDG-PET/CT in assessment of vascular compromise.


Shoulder Pain Traumatic PCAs

Shoulder Pain Traumatic PCAs. 3-phase Bone Scan Shoulder Three-phase bone scintigraphy can demonstrate a lack of blood flow to an extremity, with blood pool and delayed images showing decreased or absent uptake in the affected area [78]. However, limited resolution precludes precise anatomic definition of the site of abnormality [78]. In addition, because of the length of time required for image acquisition, scintigraphy is not the modality of choice for assessing acute vascular compromise.


Shoulder Pain Traumatic PCAs

Shoulder Pain Traumatic PCAs. CT Shoulder CT without contrast may be obtained in the setting of trauma for detection or delineation of fracture and can suggest neural injury based on expected course of the nerves. However, CT is not the modality of choice for assessment of the nerves.


Shoulder Pain Traumatic PCAs

Shoulder Pain Traumatic PCAs. CT with contrast may be obtained in the setting of trauma for detection or delineation of arterial injury, and may suggest neural injury based on the expected course of the nerves. However, CT is not the modality of choice for assessment of the nerves.


Shoulder Pain Traumatic PCAs

Shoulder Pain Traumatic PCAs. There is no role for biphasic CT in the setting of suspected traumatic nerve injury.


Shoulder Pain Traumatic PCAs

Shoulder Pain Traumatic PCAs. CT Arthrography Shoulder There is no role for CT arthrography in the setting of suspected traumatic nerve injury.


Shoulder Pain Traumatic PCAs

Shoulder Pain Traumatic PCAs. MRI Shoulder Noncontrast MRI may demonstrate discontinuity of nerves, neuromas, or perineural musculofascial edema; however, the imaging planes and resolution of routine noncontrast MRI is not adequate for confident and complete assessment of the nerves that can be injured at the shoulder [81].


Shoulder Pain Traumatic PCAs

Shoulder Pain Traumatic PCAs. There are no systematic studies on MR neurography in assessment of the peripheral nerves about the shoulder in the post-traumatic setting; however, MR neurography is gaining acceptance in assessment of peripheral nerve injuries [82]. Use of 3T imaging allows for high resolution and excellent soft-tissue contrast and can delineate focal nerve discontinuities, neuromas, and musculofascial edema [83].


Shoulder Pain Traumatic PCAs

Shoulder Pain Traumatic PCAs. There is no role for addition of contrast to the standard shoulder MRI in assessment of peripheral nerve injury.


Shoulder Pain Traumatic PCAs

Shoulder Pain Traumatic PCAs. MR Arthrography Shoulder There is no role for MR arthrography in the setting of suspected traumatic nerve injury.


Shoulder Pain Traumatic PCAs

Shoulder Pain Traumatic PCAs. US Shoulder There is no role for US in the setting of suspected traumatic nerve injury.


Shoulder Pain Traumatic PCAs

Shoulder Pain Traumatic PCAs. Bone Scan Shoulder Bone scintigraphic abnormalities may be seen in patients with complex regional pain syndrome (CRPS), formerly known as reflex sympathetic dystrophy [84-86]. Bone scintigraphy may be helpful in assessing for CRPS in patients experiencing chronic post-traumatic pain without clear etiology. Meta-analyses have found only moderate concordance between bone scintigraphy and the presence or absence of CRPS [87] and low sensitivity for detection of CRPS when compared to clinical diagnostic criteria [88-90]. However, bone scintigraphy does have high specificity and can be used to rule out CRPS [90].


Shoulder Pain Traumatic PCAs

Shoulder Pain Traumatic PCAs. Although there are references that report on studies with design limitations, 28 good-quality studies provide good evidence.


Shoulder Pain Traumatic PCAs

30-100 mSv

Shoulder Pain Traumatic PCAs. 30-100 mSv


Shoulder Pain Traumatic PCAs

10-30 mSv

Shoulder Pain Traumatic PCAs. 10-30 mSv


Shoulder Pain Traumatic PCAs

Shoulder Pain Traumatic PCAs. Supporting Documents For additional information on the Appropriateness Criteria methodology and other supporting documents go to www.acr.org/ac. References


Acutely Limping Child Up To Age 5 PCAs

Acutely Limping Child Up To Age 5 PCAs. Introduction/Background Acute onset of limp or refusal to walk is a common complaint in children, accounting for approximately 4% of visits in one pediatric emergency department [1]. The acutely limping child can be a diagnostic dilemma for clinicians. Most commonly, the acute limp is caused by minor trauma or self-limiting benign conditions but can also be caused by limb-threatening or life-threatening etiologies [2-6]. The cause of limp can usually be determined by a careful history and physical examination. The differential diagnosis of limping is broad and depends on the presence of signs of infection, localization of pain, and history of trauma [6]. The differential diagnosis in a limping child also depends on age. This discussion relates to the initial imaging of the ambulatory child under the age of 5 years who presents with an acute onset of a limp.


Acutely Limping Child Up To Age 5 PCAs

Acutely Limping Child Up To Age 5 PCAs. The presence of fever, elevated white blood cell count, elevated erythrocyte sedimentation rate, or elevated C- reactive protein suggests infection. Localization of pathology is based on site of pain, tenderness, presence of erythema, swelling, and positive physical maneuvers and signs, such as the Trendelenburg test, Galeazzi sign, Patrick/FABER test, pelvic compression test, and psoas sign [7]. A detailed analysis of gait can suggest the diagnosis [6].


Acutely Limping Child Up To Age 5 PCAs

Acutely Limping Child Up To Age 5 PCAs. Discussion of Procedures by Variant Variant 1: Child up to age 5. Acute limp. Nonlocalized symptoms. No concern for infection. Initial imaging. The most common noninfectious etiology of acute limping in children is a minor traumatic injury [8]. Unfortunately, particularly in younger children, it is common that the pain cannot be accurately localized to one focal area. When there is no concern for infection and pain cannot be localized through history or physical examination, an imaging strategy designed to first localize the source of the pain and subsequently better characterize the cause is typically pursued.


Acutely Limping Child Up To Age 5 PCAs

Acutely Limping Child Up To Age 5 PCAs. Reprint requests to: publications@acr.org


Acutely Limping Child Up To Age 5 PCAs

Acutely Limping Child Up To Age 5

Acutely Limping Child Up To Age 5 PCAs. Acutely Limping Child Up To Age 5


Acutely Limping Child Up To Age 5 PCAs

Acutely Limping Child Up To Age 5 PCAs. If initial imaging is normal but symptoms persist, follow-up radiographs or radiographs of areas besides the tibia/fibula may be useful. In the Baron et al study [13], approximately 10% of tibial fractures were only visible on follow-up radiographs and not initial imaging. One patient, who was discharged, later returned with worsening symptoms and signs of infection and was found to have spinal discitis and epidural abscess. As these examples illustrate, if the initial evaluation is negative and symptoms persist or worsen, a follow-up clinical reassessment and further imaging evaluation may be necessary.


Acutely Limping Child Up To Age 5 PCAs

Acutely Limping Child Up To Age 5 PCAs. US Hips or Lower Extremity There is no relevant literature regarding the use of ultrasound (US) in the initial evaluation of acute limp with nonlocalized symptoms and no concern for infection.


Acutely Limping Child Up To Age 5 PCAs

Acutely Limping Child Up To Age 5 PCAs. US is sensitive in evaluation of joint effusions and soft-tissue fluid collections; however, the typical field of view is small, limiting the role of US when symptoms and clinical evaluation cannot localize the site of pathology [14]. Because pain that is due to hip pathology can be referred elsewhere in the lower extremity, such as the thigh, knee, or buttock [15], US of the hip could be considered if initial radiographs are negative and symptoms persist.


Acutely Limping Child Up To Age 5 PCAs

Acutely Limping Child Up To Age 5 PCAs. 3-Phase Bone Scan Pelvis and Lower Extremity There is no relevant literature regarding the use of bone scan in the initial evaluation of acute limp with nonlocalized symptoms and no concern for infection.


Acutely Limping Child Up To Age 5 PCAs

Acutely Limping Child Up To Age 5 PCAs. Scintigraphic bone scan is sensitive in detecting bone pathology and could have a role in localizing the pathology in limping children when the examination is nonfocal, radiographs are negative, and symptoms persist [1,10,16,17]. However, a bone scan lacks specificity in this clinical scenario [1,10,16].


Acutely Limping Child Up To Age 5 PCAs

Acutely Limping Child Up To Age 5 PCAs. CT Lower Extremity There is no relevant literature regarding the use of CT in the initial evaluation of acute limp with nonlocalized symptoms and no concern for infection.


Acutely Limping Child Up To Age 5 PCAs

Acutely Limping Child Up To Age 5 PCAs. CT without intravenous (IV) contrast can be useful in a few selected cases for preoperative planning after radiographs demonstrate a complex fracture [18].


Acutely Limping Child Up To Age 5 PCAs

Acutely Limping Child Up To Age 5 PCAs. MRI Lower Extremity There is no relevant literature regarding the use of MRI pelvis/hips to feet in the initial evaluation of acute limp with nonlocalized symptoms and no concern for infection.


Acutely Limping Child Up To Age 5 PCAs

Acutely Limping Child Up To Age 5 PCAs. MRI is sensitive and specific for soft-tissue, cartilage, and bony pathology, including detection of stress reaction/fractures [19]. It may be performed in selected children when radiographs, clinical and imaging follow- up, and thorough physical examination fail to provide diagnostic clues about the source of symptoms.


Acutely Limping Child Up To Age 5 PCAs

Acutely Limping Child Up To Age 5 PCAs. MRI Whole-Body There is no relevant literature regarding the use of whole-body MRI in the initial evaluation of acute limp with nonlocalized symptoms and no concern for infection.


Acutely Limping Child Up To Age 5 PCAs

Acutely Limping Child Up To Age 5 PCAs. Because whole-body MRI is sensitive and specific for soft-tissue, joint, and bony pathology, and it allows for coverage of all musculoskeletal anatomy, it could play a role in localizing pathology in the limping child when the examination is nonfocal, the initial imaging workup is negative, and symptoms persist. Whole-body MRI has been shown to have more superior sensitivity than scintigraphic bone scans or radiography in detection of multifocal neoplastic lesions and chronic nonbacterial osteomyelitis/chronic recurrent multifocal osteomyelitis [20-22]. Whole-body MRI may be sensitive for detecting sites of involvement with inflammatory arthritides or osteonecrosis [23-25].


Acutely Limping Child Up To Age 5 PCAs

Acutely Limping Child Up To Age 5 PCAs. Variant 2: Child up to age 5. Acute limp. Pain. Localized symptoms. No concern for infection. Initial imaging. The body regions covered in this clinical scenario are: hip, femur, knee, tibia/fibula, ankle, and foot.


Acutely Limping Child Up To Age 5 PCAs

Acutely Limping Child Up To Age 5 PCAs. Localized pain may be due to trauma, in which case it is important to exclude an underlying fracture. Clinical examination and history may allow localization of the pain or injury to a specific area, which allows a more focused imaging evaluation [26].


Acutely Limping Child Up To Age 5 PCAs

Acutely Limping Child Up To Age 5 PCAs. Radiography Lower Extremity Targeted radiographs of the areas of concern have a role in evaluating for possible fracture [12,26-29]. Negative radiographs do not completely exclude the possibility of a nondisplaced fracture. Dunbar et al [30] first described


Acutely Limping Child Up To Age 5 PCAs

Acutely Limping Child Up To Age 5


Acutely Limping Child Up To Age 5 PCAs

Acutely Limping Child Up To Age 5 PCAs. Other causes of limp or pain, such as osteochondritis, apophysitis, osteonecrosis, or tumor, may be diagnosed with radiographs, though MRI has better sensitivity for such pathologies [31,32].


Acutely Limping Child Up To Age 5 PCAs

Acutely Limping Child Up To Age 5 PCAs. US Hips or Lower Extremity US has a limited field of view and has lower accuracy in detection of fractures as compared with radiographs. Weinberg et al [33] showed that clinician-performed US had a sensitivity and specificity of 73% and 92%, respectively, for the evaluation of fractures in children and young adults, with radiography or CT as the reference standard.


Acutely Limping Child Up To Age 5 PCAs

Acutely Limping Child Up To Age 5 PCAs. 3-Phase Bone Scan Pelvis and Lower Extremity There is no relevant literature regarding the use of bone scan in the initial evaluation of acute limp with localized symptoms and no concern for infection.


Acutely Limping Child Up To Age 5 PCAs

Acutely Limping Child Up To Age 5 PCAs. CT Lower Extremity There is no relevant literature regarding the use of CT in the initial evaluation of acute limp with localized symptoms and no concern for infection.


Acutely Limping Child Up To Age 5 PCAs

Acutely Limping Child Up To Age 5 PCAs. CT without IV contrast can be useful in a few selected cases for preoperative planning after radiographs demonstrate a complex or intra-articular fracture [18].


Acutely Limping Child Up To Age 5 PCAs

Acutely Limping Child Up To Age 5 PCAs. MRI Lower Extremity There is no relevant literature regarding the use of MRI in the initial evaluation of acute limp with localized symptoms and no concern for infection.


Acutely Limping Child Up To Age 5 PCAs

Acutely Limping Child Up To Age 5 PCAs. In children with persistent limp and negative radiographs, MRI is highly sensitive in detection of stress reaction/fractures [6]. When there are clinical signs of nonseptic arthritis, MRI is superior to both US and radiography in detecting inflammatory changes, early erosions, and cartilage thinning [34-37]. MRI should be performed when a tumor is suspected as it is sensitive for evaluation of bone marrow and soft-tissue extension [38].


Acutely Limping Child Up To Age 5 PCAs

Acutely Limping Child Up To Age 5 PCAs. Variant 3: Child up to age 5. Acute limp. Nonlocalized symptoms. Concern for infection. Initial imaging. Limping in the presence of one or more of the following clinical and laboratory signs should suggest the possibility of infection: fever, elevated white blood cell count, elevated erythrocyte sedimentation rate, or elevated C-reactive protein. The differential diagnoses in this scenario most commonly include septic arthritis, osteomyelitis, discitis, pyomyositis, Langerhans cell histiocytosis, and tumor (eg, leukemia, osteosarcoma, Ewing sarcoma, and metastatic disease).


Acutely Limping Child Up To Age 5 PCAs

Acutely Limping Child Up To Age 5 PCAs. When there are signs and symptoms suggestive of an infectious process, imaging has a role in substantiating the diagnosis, localizing the site of infection, evaluating for complications that require surgical intervention, and excluding other pathologies that mimic infection.


Acutely Limping Child Up To Age 5 PCAs

Acutely Limping Child Up To Age 5 PCAs. Radiography Lower Extremities Radiographs have low yield in detecting infection when symptoms and signs are not localized [39,40].


Acutely Limping Child Up To Age 5 PCAs

Acutely Limping Child Up To Age 5 PCAs. US Hips or Lower Extremity A small field of view limits the role of US when symptoms and clinical evaluation cannot localize the site of pathology [14]. Because pain that is due to hip pathology can be referred elsewhere in the lower extremity, such as the thigh, knee, or buttock [15], US of the hip could be considered even when symptoms cannot be well localized.


Acutely Limping Child Up To Age 5 PCAs

Acutely Limping Child Up To Age 5 PCAs. 3-Phase Bone Scan Pelvis and Lower Extremity Bone scan is reported to have a high sensitivity for the diagnosis of osteomyelitis [17]. Advantages of bone scan in the evaluation of infection include whole-body imaging for site localization, with the main disadvantage being the lack of soft-tissue evaluation and anatomic detail, particularly for the detection of small abscesses [16]. Bone scan may be particularly helpful in cases with implanted hardware and postoperative patients already with


Acutely Limping Child Up To Age 5 PCAs

Acutely Limping Child Up To Age 5 PCAs. Acutely Limping Child Up To Age 5 extensive edema and tissue alternations. A few case series suggest that bone scan has a lower sensitivity in the detection of source of infection relative to MRI [39-41].


Acutely Limping Child Up To Age 5 PCAs

Acutely Limping Child Up To Age 5 PCAs. MRI Lower Extremity MRI, given its sensitivity to soft-tissue and bone marrow pathology, has high accuracy in diagnosing infection, including septic arthritis, osteomyelitis, pyomyositis, and discitis [42,43], and could be considered as the initial imaging study [44]. Large field-of-view coronal T1-weighted and fluid-sensitive sequences covering from the pelvis and hips to the ankles may be performed to identify any abnormality. Inclusion of the lower thoracic spine and lumbar spine should be considered if lower extremity or hip pathology is not found and symptoms persist, as some patients with discitis may not have localized symptoms to the back [45-48]. Once localized, additional MRI sequences with smaller fields of view can be performed for further characterization [49]. Contrast administration in the MRI evaluation of suspected soft-tissue or osseous infection does not increase sensitivity or specificity but may increase reader confidence and better delineate abscesses [50,51]. Contrast administration during MRI should be considered in specific cases to improve detection of an abscess when there is significant soft-tissue edema [50,51]. An exception to this may be infants, in whom infection of the epiphyses can be occult on unenhanced MRI sequences [52]. Given these considerations, the use of IV contrast may vary with institutional protocol.


Acutely Limping Child Up To Age 5 PCAs

Acutely Limping Child Up To Age 5 PCAs. While no prospective study of MRI versus bone scan has been performed, there are retrospective studies suggesting superiority of MRI over bone scan in detecting the source of infection, with sensitivity of 99% to 100% for MRI compared to 53% to 71% for bone scan [39,40]. Because of low bone scan sensitivity for soft- tissue pathology, MRI is often obtained after a positive bone scan for further evaluation of soft-tissues, primarily to detect abscess formation that requires drainage [41].


Acutely Limping Child Up To Age 5 PCAs

Acutely Limping Child Up To Age 5 PCAs. MRI Whole-Body MRI, given its sensitivity to soft-tissue and bone marrow pathology, has high accuracy in diagnosing infection, including septic arthritis, osteomyelitis, pyomyositis, and discitis [42,43]. Like bone scan, whole-body MRI provides a total-body screen and is sensitive in detecting osseous abnormalities. As such, whole-body MRI may be an appropriate choice when there is suspicion for multifocal osteomyelitis [22,53,54]. While there is no single protocol for whole-body MRI, sequences may include the use of fluid-sensitive, T1-weighted, diffusion-weighted imaging, or chemical shift imaging, with or without the use of IV contrast [53,55].


Acutely Limping Child Up To Age 5 PCAs

Acutely Limping Child Up To Age 5 PCAs. CT Lower Extremity There is no relevant literature regarding the use of CT in the initial evaluation of acute limp with nonlocalized symptoms and concern for infection.


Acutely Limping Child Up To Age 5 PCAs

Acutely Limping Child Up To Age 5 PCAs. Variant 4: Child up to age 5. Acute limp. Symptoms localized to the hip. Concern for infection. Initial imaging. If pain or physical examination appears localized to the hip, the diagnosis is septic arthritis until proven otherwise. Septic arthritis is the most common cause of acute severe monoarticular pain in children. It typically results from hematogenous and subsequent intra-articular spread of Staphylococcus aureus, with the hip being the most common site of involvement. In some cases, septic arthritis of the hip may be secondary to adjacent osteomyelitis [56]. Septic arthritis requires rapid diagnosis and intervention to prevent permanent damage to the joint [57]. In children with signs of infection and absence of a hip effusion, a diagnosis of pelvic osteomyelitis or pyomyositis should be considered [40].


Acutely Limping Child Up To Age 5 PCAs

Acutely Limping Child Up To Age 5 PCAs. Radiography Pelvis or Lumbar Spine There are limited data to support the use of radiographs in the initial evaluation of possible septic hip. The sensitivity and specificity of radiographs for the diagnosis of septic hip are low [58].


Acutely Limping Child Up To Age 5 PCAs

Acutely Limping Child Up To Age 5 PCAs. US Hips US of the hip allows quick and accurate diagnosis of a joint effusion and can be used to guide aspiration [59,60]. Various investigators have had differing results in differentiating septic arthritis from transient synovitis of the hip when using US in combination with laboratory and clinical data [57,61]. A false-negative US is uncommon and could occur when sonography is performed within 24 hours of onset of symptoms [62]. It is important to be aware that there may be other etiologies to a hip effusion, including fractures, osteonecrosis, and juvenile idiopathic arthritis.


Acutely Limping Child Up To Age 5 PCAs

Acutely Limping Child Up To Age 5

Acutely Limping Child Up To Age 5 PCAs. Acutely Limping Child Up To Age 5


Acutely Limping Child Up To Age 5 PCAs

Acutely Limping Child Up To Age 5 PCAs. 3-Phase Bone Scan Pelvis and Lower Extremity Bone scan was found to have only 70% sensitivity, as compared to MRI, in a series of 33 patients in detecting source of infection in children presented with acute hip pain who did not have septic hip [40].


Acutely Limping Child Up To Age 5 PCAs

Acutely Limping Child Up To Age 5 PCAs. CT Pelvis CT has decreased sensitivity in the detection of bone marrow pathology and decreased soft-tissue contrast compared to MRI [63-65]. CT with IV contrast could be considered in children with contraindications to MRI [66].


Acutely Limping Child Up To Age 5 PCAs

Acutely Limping Child Up To Age 5 PCAs. MRI Pelvis MRI has high sensitivity and specificity for musculoskeletal infection, such as septic arthritis, osteomyelitis, and pyomyositis [67]. MRI detected osteomyelitis in about half of children with clinically suspected septic arthritis [56], and septic arthritis was found to be associated with osteomyelitis in MRI in about 70% of patients. Some also have soft-tissue abscesses [67]. For this reason, some advocate using MRI in the initial evaluation of suspected septic arthritis of the hips.


Acutely Limping Child Up To Age 5 PCAs

Acutely Limping Child Up To Age 5 PCAs. In children with signs of infection and acute hip pain with no evidence of septic arthritis, MRI was shown to have better sensitivity than bone scan in detection of the source of infection [40,41]. In addition, osteomyelitis of the pelvis is commonly (28%) associated with soft-tissue abscesses [68], which are easily detected by MRI. Some advocate performing MRI of the pelvis even in children with known septic arthritis because of the possibility of associated osteomyelitis and soft-tissue abscess [69].


Acutely Limping Child Up To Age 5 PCAs

Acutely Limping Child Up To Age 5 PCAs. Findings of hip effusion associated with bone marrow edema or decreased enhancement of the femoral head should raise the possibility of septic arthritis [70,71]; although, definite diagnosis of septic arthritis requires joint aspiration and fluid analysis.


Acutely Limping Child Up To Age 5 PCAs

Acutely Limping Child Up To Age 5 PCAs. Contrast administration in the MRI evaluation of suspected soft-tissue or osseous infection does not increase sensitivity or specificity but increases reader confidence and better delineates abscesses [50,51]. An exception to this may be in infants and younger children with an abundance of nonossified cartilage, in whom infection limited to the intrinsically hyperintense cartilaginous growth plate and epiphyses/apophyses can be occult on unenhanced MRI sequences. Given these considerations, the use of IV contrast may vary with institutional protocol.


Acutely Limping Child Up To Age 5 PCAs

Acutely Limping Child Up To Age 5 PCAs. Variant 5: Child up to age 5. Acute limp. Symptoms localized to lower extremity (not pelvis or hips). Concern for infection. Initial imaging. The body regions covered in this clinical scenario are: femur, knee, tibia/fibula, ankle, and foot.


Acutely Limping Child Up To Age 5 PCAs

Acutely Limping Child Up To Age 5 PCAs. Radiography Lower Extremity There are limited evidence to support the use of radiographs for the acute evaluation of localized infection. The sensitivity of radiographs in detecting early osteomyelitis or soft-tissue infection is low [39,40]. While soft-tissue signs of swelling and edema may be detected early by radiographs and nonspecific signs, such as periosteal reaction and osteopenia, detection of bone destruction may take up to 3 weeks after onset of symptoms [54,64,72].


Acutely Limping Child Up To Age 5 PCAs

Acutely Limping Child Up To Age 5 PCAs. US Lower Extremity US may play a role in diagnosing pyomyositis, in which inflammatory change may lead to an altered sonographic appearance in affected muscle [73,74]. Because US will not penetrate cortex, it is unable to evaluate bone marrow and is not sensitive for osteomyelitis. US is sensitive to subperiosteal collections, which can be seen with osteomyelitis [54,75].


Acutely Limping Child Up To Age 5 PCAs

Acutely Limping Child Up To Age 5 PCAs. 3-Phase Bone Scan Pelvis and Lower Extremity Bone scan has been reported to have a high sensitivity for the diagnosis of osteomyelitis, albeit with lower reported specificity. However, its utility is greatest when symptoms cannot be localized. The main limitation of bone scan with a localized examination is in the detection of soft-tissue abscess [39,41].


Acutely Limping Child Up To Age 5 PCAs

Acutely Limping Child Up To Age 5 PCAs. CT Lower Extremity CT has decreased sensitivity in the detection of bone marrow pathology and decreased soft-tissue contrast compared to MRI [63-65]. CT with IV contrast can be considered when soft-tissue infection is of concern or in children with contraindications to MRI [66].


Acutely Limping Child Up To Age 5 PCAs

Acutely Limping Child Up To Age 5 PCAs. Acutely Limping Child Up To Age 5 MRI Lower Extremity MRI, given its sensitivity to musculoskeletal injury and inflammation, has high accuracy in diagnosing infection, specifically osteomyelitis and pyomyositis [43,76]. Contrast administration improves detection of soft-tissue abscesses in selected patients with soft-tissue edema [50,51]. Because of low bone scan sensitivity for soft-tissue pathology, MRI may sometimes need to be obtained after a positive bone scan for further evaluation of soft- tissues pathology mainly to detect any abscess formation that requires drainage [41].


Acutely Limping Child Up To Age 5 PCAs

Acutely Limping Child Up To Age 5 PCAs. Contrast administration in the MRI evaluation of suspected soft-tissue or osseous infection does not increase sensitivity or specificity but may increase reader confidence and better delineate abscesses [50,51]. Contrast administration during MRI should be considered in specific cases to improve detection of small abscesses when there is significant soft-tissue edema [50,51]. The need for sedation in young patients undergoing MRI is a consideration.


Acutely Limping Child Up To Age 5 PCAs

Acutely Limping Child Up To Age 5 PCAs. MRI Whole-Body There is no relevant literature regarding the use of whole-body MRI in the initial evaluation of acute limp with localized symptoms to the lower extremity and concern for infection.


Acutely Limping Child Up To Age 5 PCAs

Acutely Limping Child Up To Age 5 PCAs. Whole-body MRI may be very sensitive for osteomyelitis. However, its greatest utility is when multifocal osteomyelitis is suspected or symptoms cannot be localized [22,53,54].


Acutely Limping Child Up To Age 5 PCAs

Acutely Limping Child Up To Age 5 PCAs. Although there are references that report on studies with design limitations, 7 good-quality studies provide good evidence.


Acutely Limping Child Up To Age 5 PCAs

Acutely Limping Child Up To Age 5

Acutely Limping Child Up To Age 5 PCAs. Acutely Limping Child Up To Age 5


Acutely Limping Child Up To Age 5 PCAs

Acutely Limping Child Up To Age 5 PCAs. Supporting Documents For additional information on the Appropriateness Criteria methodology and other supporting documents go to www.acr.org/ac.


Anorectal Disease

Anorectal Disease. Introduction/Background Inflammatory and infectious disorders of the anorectum are commonly encountered in clinical practice, but their exact incidence is unknown. They encompass a variety of anorectal disorders in a diverse population of patients who may present to the emergency department, urgent care clinic, primary care physician, or subspecialty physician such as a gastroenterologist or colorectal surgeon. Patients with inflammatory and infectious disorders of the anorectum may come in need of medical attention with acute symptoms such as pain, tenesmus, discharge, bleeding, and/or findings of sepsis. Other patients may have chronic symptoms, or their complaints may relate to a prior surgical procedure or underlying disease. Depending upon the condition and presentation, a variety of imaging modalities may be used for the initial evaluation of an anorectal complaint.


Anorectal Disease

Anorectal Disease. Imaging may also be helpful for planning the management of rectovaginal fistulas that are the consequence of obstetric trauma from childbirth, iatrogenic anorectal or rectovaginal fistulas that are caused by radiation or surgical complications, and fistulas that result from other forms of trauma.


Anorectal Disease

Anorectal Disease. The initial imaging in 4 anorectal disease categories is covered in this document: suspected perianal disease (perianal fistula and abscess); suspected rectal fistula (rectovescicular or rectovaginal); suspected proctitis or pouchitis; and suspected complication after proctectomy, coloproctectomy, or colectomy with pouch or other anastomosis.


Anorectal Disease

Anorectal Disease. Special Imaging Considerations Anorectal Fistulae and Malignancy Though the focus of this topic is on inflammatory and infectious disorders of the anorectum, it is important to recognize that inflammatory disease of the anorectum may be a complication of malignancy or associated with malignancy. For example, approximately 11% of colovesical and colovaginal fistulae are caused by malignancy [1]. Recently, carcinoma has been reported in association with anal fistulae in Crohn disease (CD), and carcinomas may rarely arise in chronic fistula in the anorectum [2,3]. Consequently, the concern for malignancy should be raised when the imaging findings of a soft mass, mass-like thickening of the wall of the anorectum, or malignant- appearing lymphadenopathy are present during evaluation of the anorectum for suspected benign inflammatory disease.


Anorectal Disease

Anorectal Disease. OR aMedstar Georgetown University Hospital, Washington, District of Columbia. bCleveland Clinic, Cleveland, Ohio. cPanel Chair, University of Wisconsin Hospital & Clinics, Madison, Wisconsin. dPanel Vice-Chair, University of California San Diego, San Diego, California. eMayo Clinic, Rochester, Minnesota, American Gastroenterological Association. fBoston University Medical Center, Boston, Massachusetts. gMedstar Georgetown University Hospital, Washington, District of Columbia, Primary care physician. hH. Lee Moffitt Cancer Center and Research Institute, Tampa, Florida. iVirginia Tech Carilion School of Medicine, Roanoke, Virginia. jMassachusetts General Hospital, Boston, Massachusetts. kOregon Health and Science University, Portland, Oregon. lDuke University Medical Center, Durham, North Carolina. mEmory University, Atlanta, Georgia. nUniversity of Alabama at Birmingham, Birmingham, Alabama. oUniversity of California San Diego, San Diego, California. pUniversity of California San Francisco, San Francisco, California. qCleveland Clinic Florida, Weston, Florida, American College of Surgeons. rSpecialty Chair, Virginia Commonwealth University Medical Center, Richmond, Virginia.


Anorectal Disease

Anorectal Disease. The American College of Radiology seeks and encourages collaboration with other organizations on the development of the ACR Appropriateness Criteria through society representation on expert panels. Participation by representatives from collaborating societies on the expert panel does not necessarily imply individual or society endorsement of the final document.


Anorectal Disease

Anorectal Disease. Reprint requests to: publications@acr.org


Anorectal Disease

Anorectal Disease. Anorectal Disease Discussion of Procedures by Variant Variant 1: Suspected perianal disease. Abscess or fistula. Initial imaging. Anorectal abscesses result from infection of the intersphincteric anal glands. Obstruction of the draining duct may produce an intersphincteric abscess or the infection may rupture through the external sphincter to form an abscess in the ischiorectal or ischioanal spaces. Cephalad extension results in a high intramuscular or perirectal abscess, or a supralevator abscess if it extends above the levator muscles. Posterior extension may result in a horseshoe abscess in the intersphincteric plane or ischiorectal fossa [4]. Patients with anorectal abscess may present with pain that is typically throbbing, visible redness and swelling of the anus, and/or sepsis. On physical examination, there is often tenderness to palpation and an area of fluctuance. In some cases, the abscess may be occult on physical examination.


Anorectal Disease

Anorectal Disease. The majority of anal fistulae (fistula-in-ano) arise from a preexisting abscess and as such are believed to represent a spectrum of the same disease. Clinically, patients with fistula-in-ano present with drainage of blood, pus, or fecal material from an external opening in the perianal region, intermittent pain, and perianal itching. The majority of patients with fistula-in-ano are male (2:1) and have a mean age at presentation of 40 years [5]. Other diseases that may cause anal fistula include CD, radiation proctitis, foreign body, prior anal surgery, infections (such as human immunodeficiency virus [HIV], tuberculosis, actinomycosis), and malignancy [6]. Perianal fistulae are a very common component of CD, occurring in 13% to 27% of these patients [7,8]. Perianal fistulae may be the initial manifestation of CD in up to 81% of patients who develop perianal disease, and in a small number of patients, it is the only manifestation of their disease [9]. Complex and multifocal fistulae are more common in CD.


Anorectal Disease

Anorectal Disease. Imaging is used in suspected cases of anorectal abscess and/or fistula to confirm the diagnosis, assist in surgical planning, predict surgical outcome, assess for recurrent or residual disease, and monitor medical therapy in patients with CD [10].


Anorectal Disease

Anorectal Disease. CT Pelvis The appropriate CT protocol for imaging a patient with an anorectal complaint depends upon the presentation and differential diagnosis. Intravenous (IV) contrast is preferred to a noncontrast examination to help visualize and characterize fluid collections, abscesses, and fistulous tracts. Water-soluble rectal contrast is generally not necessary to diagnose a rectal abscess and may be challenging to administer depending on symptom severity. However, rectal contrast may help delineate perforation or leak in a patient with a history of trauma or recent surgery. Water-soluble rectal contrast is preferred over barium to avoid the possibility of barium spilling into the peritoneal cavity or spaces of the extraperitoneal pelvis. Water-soluble rectal contrast is also preferred in a patient who could potentially be undergoing surgery.


Anorectal Disease

Anorectal Disease. CT is commonly used in the acute setting to evaluate for anorectal abscess. The inherent lack of contrast resolution of CT limits the differentiation of subtle attenuation changes to differentiate small abscesses and fistulae from the anal sphincter complex and the soft tissue of the pelvic floor. To our knowledge, there is no recent literature evaluating the accuracy of modern CT technology for the detection of anorectal abscesses and there are no studies comparing IV contrast-enhanced scans to scans obtained without IV contrast. CT with and without IV contrast would only be useful when there is benefit from dual-phase imaging (eg, gastrointestinal bleeding). However, IV contrast is important to delineate rim-enhancement of fluid collections to aid in the diagnosis of abscess. The reported sensitivity of CT for anorectal abscess is 77% [11]. Comparing CT with endoanal ultrasound (US) and surgical findings, only 24% of perianal fistulae were correctly classified on CT, as compared with 82% by endoanal US in a small series of 25 patients reported by Schratter-Sehn et al [12].


Anorectal Disease

Anorectal Disease. Fluoroscopy Contrast Enema Fluoroscopic contrast enema is not useful in this clinical scenario because it cannot assess the presence or absence of an abscess or fistula tract. There is no relevant literature regarding the use of contrast enema in the evaluation of perianal disease.


Anorectal Disease

Anorectal Disease. Fluoroscopy Fistulography Fluoroscopic fistulography is performed by cannulating the external opening of a fistula with a small-gauge catheter, such as an IV catheter, pediatric feeding tube, or lacrimal cannula. Scout radiographs are obtained prior to careful injection of water-soluble contrast material into the fistula tract while obtaining spot radiographs [13]. Care


Anorectal Disease

Anorectal Disease

Anorectal Disease. Anorectal Disease


Anorectal Disease

Anorectal Disease. should be taken not to inadvertently obscure a distal fistula with the enema or catheter tip or the balloon of a catheter. Fistulography may also be performed with CT by injecting a dilute water-soluble contrast material into an external opening of a fistula; however, there is limited published experience with this technique [14,15].


Anorectal Disease

Anorectal Disease. Fluoroscopic fistulography is rarely performed for perianal disease and has been replaced by modern cross-sectional imaging in this setting. Data on the accuracy of fluoroscopic fistulography are available from small series reported in older medical literature. Weisman et al [13] reported the highest sensitivity (89%) for identification of the primary tract in a retrospective review of 27 patients. In contrast, Kuijpers and Schulpen [16] found fistulography was accurate in only 16% of patients in a retrospective review of 25 patients [16]. The limitations of fistulography include lack of filling of the entire tract or extensions of the tract because inflammatory debris in the tract may prevent contrast filling. In these cases, the internal opening may not be defined. Furthermore, the anal sphincter complex and levator ani are not visualized fluoroscopically; as such, the relationship of the fistula to these structures cannot be defined.


Anorectal Disease

Anorectal Disease. Pelvic MRI with a multichannel phased array body coil has become the standard for imaging perianal fistula, especially those associated with CD, because they are more frequently complex with clinically occult tracts. Imaging with a body coil is better tolerated and is not limited by the field of view compared with MRI with an endoanal coil. The surgical concordance with fistula detection has been shown to be better with a body coil (96%) compared with an endoanal coil (68%) [20].


Anorectal Disease

Anorectal Disease. In multiple studies, MRI has been shown to have high sensitivity and specificity for the evaluation of perianal fistula. The meta-analysis by Zbar and Armitage [21] showed MRI had a sensitivity ranging from 81% to 100% and specificity from 67% to 100%, with accuracy for identification of the internal opening of 74% to 97%, and delineation of horseshoe fistula of 97% to 100% [21]. Sahni et al [22] showed that, for diagnosis of the primary fistula in CD patients, MRI had an accuracy of 64% to 100%. Comparing MRI to examination under anesthesia with or without endoanal US, the sensitivity and specificity for discriminating complex from simple perianal fistula was 97% and 96%, 92% and 85% for MRI, and 75% and 64% for endoanal US.


Anorectal Disease

Anorectal Disease. Though fistula can be readily identified on MRI without IV contrast as hyperintense tracts on FSE T2-weighted sequences and short-tau inversion recovery sequences, the use of IV contrast facilitates visualization because tracts with active inflammation will avidly enhance and small associated abscesses will show ring enhancement around a central fluid collection. IV contrast enables the differentiation of inactive tracts containing granulation tissue, which diffusely enhance from active tracts that have ring or rim-like enhancement [18].


Anorectal Disease

Anorectal Disease. Lo Re et al [23] retrospectively evaluated MRI in 31 patients with CD suspected of having perianal fistula and a surgical examination under anesthesia showing that short-tau inversion recovery sequences were equivalent to IV contrast-enhanced fat-suppressed T1-weighted sequences in detection and classification of anal fistula with sensitivity of 96%, specificity of 75%, positive predictive value (PPV) of 93%, and negative predictive value (NPV) of 86% for both sequences [23]. However, their study did not evaluate tract activity. In another retrospective study of 17 patients that underwent MRI prior to surgery, the contribution of MRI sequences to fistula classification was evaluated. All 3 readers showed statistically significant concordance between fistula classification and surgery with IV contrast-enhanced fat-suppressed T1-weighted sequences. The highest concordance for all 3 readers was reached


Anorectal Disease

Anorectal Disease. with the combination of T2-weighted sequences and IV contrast-enhanced fat-suppressed T1-weighted sequences [24].


Anorectal Disease

Anorectal Disease. Finally, Dohan et al [19] evaluated the addition of diffusion imaging in a retrospective study of 24 patients with perianal fistula that went to surgery. The sensitivity for anal fistula detection for fat-suppressed FSE T2-weighted sequences was 91.2% and for diffusion imaging was 100%, with statistically significant greater fistula conspicuity on diffusion imaging than fat-suppressed FSE T2-weighted sequences.


Anorectal Disease

Anorectal Disease. Radiography Pelvis Radiography is not useful in this clinical scenario because it cannot assess the presence or absence of an abscess or fistula tract. There is no relevant literature to support the use of radiography in the evaluation of perianal fistula.


Anorectal Disease

Anorectal Disease. In a recent study of 122 patients by Sun et al [27], the reported sensitivity, specificity, and accuracy for the diagnosis of perianal fistula compared with surgery was 92%, 100%, and 93%, respectively. This study reported an accuracy of identification of the internal opening of the fistula of 95%. In an earlier study of 104 patients by Buchanan et al [28], comparing endoanal US with MRI, endoanal US correctly classified 81% of perianal fistulae compared with 90% by MRI. Their accuracy for detection of the internal opening was 91% by endoanal US and 97% by MRI. Endoanal US is limited by the field of view and depth of penetration. Accuracy for identification of extrasphincteric and suprasphincteric tracts (50% and 67%, respectively) is lower compared with transsphincteric and intersphincteric tracts (93% and 88%, respectively) [27]. Other limitations include obscuration of the tract or secondary extensions by gas in the tract or gas in an associated abscess. In patients with recurrent disease, it may be impossible to distinguish tracts with active inflammation from those with fibrosis and granulation tissue, which is often a clinical question in patients with CD.


Anorectal Disease

Anorectal Disease. Hydrogen peroxide may be injected into the external opening of the fistula during endoanal US to enhance visualization of fistula tracts [29]. A tract filled with hydrogen peroxide is brightly hyperechoic on endoanal US, improving its visualization and connection to abscess cavities as well as differentiating it from scar tissue [25].


Anorectal Disease

Anorectal Disease. Variant 2: Suspected rectal fistula. Rectovesicular or rectovaginal. Initial imaging. Rectovaginal and rectovesicular fistulae are uncommon. The most common cause of a rectovaginal fistula is obstetric or vaginal trauma (88% of cases) [32], followed by CD, which accounts for approximately 9% of cases [33]. Other causes include radiation; pelvic infections (diverticulitis, tuberculosis, lymphogranuloma venereum, human papilloma virus, HIV, cytomegalovirus, and schistosomiasis); malignancies of the anorectum, perineum, and gynecologic organs; and iatrogenic injury and postoperative complications. Upon initial imaging, the organ of origin may be unknown. Rectovaginal fistulae are subclassified as high or low fistulae. High fistula, referred to as rectovaginal fistula, are communications to the rectum, proximal to the anal sphincter. These often involve the posterior vaginal fornix. Low fistula are anovaginal, which are communications from the anal sphincter complex to the lower half of the vagina [34]. Women with rectovaginal or anovaginal fistulae present with stool, gas, or odorous


Anorectal Disease

Anorectal Disease. mucopurulent discharge from the vagina. These symptoms may be confused for incontinence. Other symptoms include dyspareunia, perineal pain, and recurrent vaginal infections. Rectovesicular fistulae are characterized by the clinical presentation of pneumaturia or fecaluria, which are pathognomonic [1]. Recurrent urinary tract infection may also be a presenting manifestation. Diverticulitis, CD, colorectal or pelvic malignancies, radiation, iatrogenic injury, and postoperative complications are the most common causes.


Anorectal Disease

Anorectal Disease. CT Pelvis The appropriate CT protocol for imaging a patient with an anorectal complaint depends upon the presentation and differential diagnosis. IV contrast is preferred to a noncontrast examination to help visualize and characterize fluid collections, abscesses, and fistulous tracts. CT without contrast is not useful in this clinical scenario. CT with and without IV contrast would only be useful when there is benefit from dual-phase imaging, but is not typically performed in this scenario. Water-soluble rectal contrast is generally not necessary to diagnose a rectal abscess and may be challenging to administer, depending on symptom severity. However, rectal contrast may help delineate perforation or leak in a patient with a history of trauma or recent surgery. Water-soluble rectal contrast is preferred over barium to avoid the possibility of barium spilling into the peritoneal cavity or spaces of the extraperitoneal pelvis. Water-soluble rectal contrast is also preferred in a patient who could potentially be undergoing surgery.


Anorectal Disease

Anorectal Disease. CT provides important information in the diagnosis of the underlying etiology of the fistula, as well as detecting the course and locations of fistulae. To our knowledge, there are no data in the literature regarding the use of IV contrast in the detection of rectovaginal or rectovesicular fistula. Water-soluble contrast should be placed in the bowel or bladder to try to opacify fistulous tracts, depending upon the clinically suspected location of the tract. The bladder can be opacified retrograde (CT cystogram) or antegrade with delayed imaging after IV contrast administration. Kuhlman et al [35] reported an accuracy of 60% for the CT detection of enterovaginal or vesicovaginal fistula by the identification of contrast material in the vagina from the bowel or bladder. In a study of 37 patients with colovaginal and colovesicular fistulae, CT had a diagnostic sensitivity of 76.5% for fistula detection and 94.1% for defining the etiology of the fistula [1]. However, this study does not report how the diagnosis of fistula was made and what type of contrast material was used.


Anorectal Disease

Anorectal Disease. Fluoroscopy Contrast Enema Fluoroscopic contrast enemas performed for the diagnosis of perforation or leak, rectovaginal or rectovesicular fistula, pouchitis, or proctitis can be performed with water-soluble contrast or barium. Though this procedure is reported to have low sensitivity and specificity as detailed in the following paragraph, it may be useful for observing subtle fistulas. In general, water-soluble contrast is preferred if a leak or perforation are suspected to avoid barium spillage into the peritoneal cavity or extraperitoneal pelvis. Using barium may also interfere with a subsequent CT scan because of the streak artifact that it causes on CT. Care should be taken not to inadvertently obscure a distal fistula with the enema or catheter tip or the balloon of a catheter.


Anorectal Disease

Anorectal Disease. The performance of contrast enema for the detection of rectovaginal fistulas is reported in small series from older published literature. In 13 enemas performed by Giordano et al [36], the overall sensitivity was 7.7% for all fistula and 9% for those that involved the colon only. In a previous series of sigmoid vaginal fistulae, contrast enema detected the fistulae in 34% of cases [37]. For fistula to the urinary tract, Amendola et al compared contrast enema and cystography, which showed 50% and 30% of fistula, respectively, in 28 patients with surgically proven colovesicular fistula [38].


Anorectal Disease

Anorectal Disease. Fluoroscopy Cystography The data on diagnosis of rectovesicular fistula by cystography is limited to small series in older medical literature. In series of 30 patients with enterovesicular fistula, Hsieh et al [39] reported 90% were detected by cystography and 75% by contrast enema.


Anorectal Disease

Anorectal Disease. Fluoroscopy Vaginography Fluoroscopic vaginography is performed after obtaining anterolateral and lateral scout radiographs or spot films. A large-gauge Foley catheter, such as a 26-guage with a 30-mL balloon, is placed in the vaginal lumen. The balloon is inflated to prevent the spillage of contrast material out of the vagina. Water-soluble contrast is injected under fluoroscopic guidance, and spot radiographs are obtained in the anteroposterior, right and left, oblique, and lateral views. Water-soluble contrast is preferred over barium because the endometrial cavity may fill in normal patients, and contrast may thus spill into the peritoneal cavity. Vaginography may also be performed with CT [40]. An unenhanced scan is obtained prior to vaginal opacification. The vagina is opacified in the same manner as in


Anorectal Disease

Anorectal Disease

Anorectal Disease. Anorectal Disease


Anorectal Disease

Anorectal Disease. fluoroscopy; however, the water-soluble contrast is diluted with sterile water or normal saline (1/10, V/V) [40]. A second CT is obtained after vaginal filling. It may be acquired with or without IV contrast, depending upon the clinical indication.


Anorectal Disease

Anorectal Disease. Giordano et al [36] reported a sensitivity of 79% and PPV of 100% for fluoroscopic vaginography for identification of fistulous tracts in 27 patients with suspected fistulae. Earlier series in a smaller number of patients reported sensitivities of 100% [41,42]. Limitations of vaginography include occlusion of low fistula by the Foley catheter balloon and completely filling complex fistulous tracts that may have several branches. The high sensitivity and PPV supports the use of this procedure in certain clinical scenarios.


Anorectal Disease

Anorectal Disease. MRI Pelvis Rectovaginal and anovaginal fistula may be visualized on MRI performed with a phased array body coil, but to our knowledge, there are no published studies reporting the accuracy of fistula detection. As such, the advantages of scanning with or without IV contrast have not been studied. Based on our knowledge of anorectal fistula, there is a clear advantage to using IV contrast to visualize collapsed tracts that do not contain fluid and would be difficult to see on T2-weighted sequences. MRI pelvis without IV contrast may be helpful in certain clinical situations but is not as good as one performed with IV contrast. Stoker et al [43] compared endoluminal coil MRI with and without IV contrast to endoluminal US, reporting a PPV for detection of fistula tracts of 92% and 100%, respectively.


Anorectal Disease

Anorectal Disease. Radiography Pelvis Radiography is not useful in this clinical scenario because it cannot assess the presence or absence of an abscess or fistula tract.


Anorectal Disease

Anorectal Disease. US Pelvis Transrectal Yee et al [44] reported that endoluminal US detected only 28% of rectovaginal fistula in 25 patients prior to surgical repair. However, more recent reports show improved detection; consequently, this procedure can be useful in certain clinical situations for fistula detection. In 28 patients, Yin et al [45] had a PPV of 100% for the identification of the anorectal opening of the fistula and 93% for the identification of the vaginal opening, and an overall PPV of the fistula of 90%. The limitation of endoluminal US is identification of complex fistulas with secondary branches, visualization of occluded branches, and visualization of fistula that extend beyond the field of view.


Anorectal Disease

Anorectal Disease. Variant 3: Suspected proctitis or pouchitis. Initial imaging. Proctitis, inflammation of the rectum, is a common manifestation of inflammatory bowel disease (ulcerative colitis and CD). Other causes include infections (gonorrhea, chlamydia, herpes simplex virus, HIV/acquired immunodeficiency syndrome), radiation, and ischemia. Patients present with rectal pain, discomfort, tenesmus, purulent discharge, abdominal pain, and urgency. In most patients, imaging is not required. However, if a more complex disease is clinically suspected, imaging may be indicated to define the extent of disease and/or complications.


Anorectal Disease

Anorectal Disease. An ileal pouch anal anastomosis (IPAA), also known as a J-pouch, is the most common surgical approach for creating a continent reservoir following total proctocolectomy. This is typically performed in a two-stage procedure in patients with ulcerative colitis or familial adenomatous polyposis. Pouchitis is a common complication of IPAA, occurring in approximately 20% of patients within 1 year of surgery and 50% of patients within 10 years of surgery [46]. Pouchitis may be caused by primary infection or an immune response to an altered microbiome in the pouch lumen or mucosa. Patients may present with increased stool frequency and fluidity, tenesmus, incontinence, pain, malaise, fever, or bleeding. The symptoms of pouchitis overlap with other postoperative complications, such as dehiscence and abscess, as well as occult CD such as in patients that have presumed ulcerative colitis with undiagnosed CD or subsequently developed CD [47]. Imaging is an important complementary technique to endoscopy with biopsy to accurately diagnose and manage inflammation in the pouch.


Anorectal Disease

Anorectal Disease. CT Enterography CT enterography techniques provide better visualization of the small bowel compared with routine CT. To optimize small-bowel distention and visualization of the mucosa, patients ingest a large volume (1,000 to 2,000 cc) of neutral contrast material (such as low w/v barium solutions, water, polyethylene glycol, or methylcellulose suspensions) prior to the examination. IV contrast enhances the small-bowel wall such that it is well seen adjacent to the neutral intraluminal contrast. Single- or dual-phase (arterial and portal venous, respectively) acquisitions may be obtained.


Anorectal Disease

Anorectal Disease. Using CT findings of inflammation (wall thickening, mucosal hyperenhancement, mural stratification, peripouch stranding, peripouch hyperemia, and peripouch abscess, fistula, or sinus tract), Liszewski et al [48] showed that IV


Anorectal Disease

Anorectal Disease. contrast-enhanced CT enterography had a 90% sensitivity, 67% specificity, 90% PPV, 67% NPV, and 85% accuracy for diagnosis of pouchitis when more than 2 signs of inflammation were present.


Anorectal Disease

Anorectal Disease. CT Pelvis The appropriate CT protocol for imaging a patient with an anorectal complaint depends upon the presentation and differential diagnosis. IV contrast is preferred to a noncontrast examination to help visualize and characterize fluid collections, abscesses, and fistulous tracts. CT without contrast is not useful in this clinical scenario. CT with and without IV contrast would only be useful when there is benefit from dual-phase imaging, but it is not typically performed in this scenario. Water-soluble rectal contrast is generally not necessary to diagnose a rectal abscess and may be challenging to administer, depending on symptom severity. However, rectal contrast may help delineate perforation or leak in a patient with a history of trauma or recent surgery. Water-soluble rectal contrast is preferred over barium to avoid the possibility of barium spilling into the peritoneal cavity or spaces of the extraperitoneal pelvis. Water-soluble rectal contrast is also preferred in patients who could potentially be undergoing surgery.


Anorectal Disease

Anorectal Disease. CT is often the initial examination for patients with clinical findings of proctitis or pouchitis because of its ability to evaluate inflammatory thickening of the rectal or pouch wall, associated abscess, possible fistula, or anastomotic leak in an IPAA. IV contrast-enhanced CT is preferred over a noncontrast CT because the presence of IV contrast will allow detection of abnormal enhancement of the bowel wall as well as the presence of rim-enhancement that would suggest abscess in any associated fluid collection. To our knowledge, there are no studies in the literature using modern CT technology that evaluate the accuracy of routine pelvic CT with or without IV contrast for the diagnosis of proctitis or pouchitis.


Anorectal Disease

Anorectal Disease. FDG-PET/CT Skull Base to Mid-Thigh Fluorine-18-2-fluoro-2-deoxy-D-glucose (FDG)-PET/CT has been reported to be a useful tool in assessing the degree of inflammatory activity in patients with ulcerative colitis and CD [49,50]. Shyn et al [51] compared FDG- PET/CT enterography to conventional CT enterography in evaluating patients with CD. In this study, FDG-PET/CT enterography showed sites of active inflammation in 3 of 13 cases (23.1%) that were not seen on CT enterography, though these areas were not in the rectum or a surgical pouch. To our knowledge, there is no relevant recent literature regarding the use of FDG-PET/CT in the evaluation of suspected proctitis or pouchitis.


Anorectal Disease

Anorectal Disease. Fluoroscopy Contrast Enema Fluoroscopic contrast enemas performed for the diagnosis of perforation or leak, rectovaginal or rectovesicular fistula, pouchitis, or proctitis can be performed with water-soluble contrast or barium. In general, water-soluble contrast is preferred if a leak or perforation is suspected in order to avoid barium spillage into the peritoneal cavity or extraperitoneal pelvis. Using barium may also interfere with a subsequent CT scan because of the streak artifact that it causes on CT.


Anorectal Disease

Anorectal Disease. A retrospective review by Brown et al [52] published in 1990 compared CT to fluoroscopic examination of patients with IPAA. Some of the fluoroscopic examinations were performed antegrade through the distal limb of the loop ileostomy, whereas others were performed retrograde. In these 18 patients, 10 had infectious symptoms and 8 did not. CT more clearly delineated the site and extent of abscess in 9 patients with infectious symptoms compared with the fluoroscopic studies [52]. However, this study did not evaluate the sensitivity or specificity of each examination, neither did it directly address pouchitis. To our knowledge, there is no recent literature evaluating fluoroscopic contrast enema for the diagnosis of proctitis or pouchitis.


Anorectal Disease

Anorectal Disease. MR Enterography Pouchitis can also be evaluated as part of MR enterography. MR enterography is commonly performed with biphasic oral contrast agents that produce low signal intensity on T1-weighted sequences and high signal intensity on T2-weighted sequences because they allow excellent characterization of bowel wall enhancement on IV contrast- enhanced T1-weigheted sequences. These agents include low weight/volume barium solutions, water, polyethylene glycol, and methylcellulose. Patients ingest a large volume of the oral contrast prior to the examination. Administering an antispasmodic drug such as glucagon is useful for reducing motion artifact caused by bowel peristalsis. Both FSE T2-weighted and steady-state free precession T2-weighted sequences are generally performed to compensate for limitations of each in addition to dynamic IV contrast-enhanced sequences.


Anorectal Disease

Anorectal Disease. In 28 patients who underwent colectomy with IPAA, Sahi et al [53] compared MR enterography, pouch endoscopy, and biopsy. They found that the presence of 4 or more MR enterography features of inflammation had the best correlation with endoscopic findings (86% sensitivity, 79% specificity, 80% PPV, 85% NPV, and 82% accuracy).


Anorectal Disease

Anorectal Disease

Anorectal Disease. Anorectal Disease


Anorectal Disease

Anorectal Disease. MRI is an excellent imaging modality for the evaluation of inflammatory disease of the rectum or IPAA. Using IV contrast material enhances the ability to diagnose inflammation, adding the findings of mucosal hyperenhancement to other findings such as wall thickening, submucosal edema seen on T2-weighted sequences, and mucosal ulceration. Additional findings, such as perirectal and perianal fistula and abscess, can also be seen. In a study of 58 patients with CD who had MRI and colonoscopy, several MRI features correlated with endoscopic diagnosis of proctitis, including wall thickness, submucosal fat, increased perimural signal intensity on T2-weighted sequences, increased perimural enhancement, creeping fat, and mesorectal lymph node size [54]. In another study of 9 patients, MRI had sensitivity and specificity of 100% for pouchitis as validated by pathology, using the criteria of increased wall thickness and enhancement [55].


Anorectal Disease

Anorectal Disease. Radiography Pelvis Radiography is not useful in this clinical scenario because it cannot assess inflammation of the rectum or ileoanal pouch. There is no relevant literature to support the use of radiography in the evaluation of suspected proctitis or pouchitis.


Anorectal Disease

Anorectal Disease. US Pelvis Various US techniques (transabdominal, transperineal, transvaginal, and endorectal) can be used to assess the rectum or IPAA. In one study using endorectal US to evaluate radiation proctitis as compared with colonoscopy, endorectal US had sensitivity of 86.4%, specificity of 66.7%, PPV of 76.0%, NPV of 80.0%, and overall accuracy of 77.5% in differentiating mild from severe radiation proctitis by using blurred rectal wall stratification and wall vascularity [56]. There is no relevant recent literature regarding the use of US in the evaluation of suspected pouchitis.


Anorectal Disease

Anorectal Disease. WBC Scan Abdomen and Pelvis In 1990, Thoeni et al [57] published a retrospective study of 55 patients who underwent total colectomy and IPAA. They compared CT, indium-11 (In-111) scintigraphy, and fluoroscopic pouchography for the detection of pouchitis, abscess, and fistula. For pouchitis, the sensitivity of CT, In-111 scintigraphy, and pouchography was 71%, 80%, and 53%, respectively. To our knowledge, there is no recent literature evaluating and comparing scintigraphy for the diagnosis of proctitis or pouchitis.


Anorectal Disease

Anorectal Disease. There is no relevant recent literature regarding the use of Tc-99m white blood cell (WBC) scan in the evaluation of suspected proctitis or pouchitis.


Anorectal Disease

Anorectal Disease. prolapse in the case of IPAA. A meta-analysis of complications after total proctocolectomy with IPAA performed by Hueting et al [59] showed a pooled incidence of 9.5% for pelvic sepsis, 5.5% for pouch-related anal or vaginal fistula, 9.2% for strictures, and 13.1% for small-bowel obstruction. The initial imaging modality for patients with a suspected postoperative complication may vary based upon the suspected complication. CT is often the first imaging modality used for patients who return following surgery with acute pain, sepsis, or signs of bowel obstruction.


Anorectal Disease

Anorectal Disease. CT Abdomen and Pelvis CT abdomen and pelvis may be preferred over CT pelvis alone, depending upon the clinical scenario or specific type of operation performed. To our knowledge, there are no studies comparing noncontrast CT to IV contrast- enhanced CT for the detection of postoperative complications. However, IV contrast does improve the detection of abscesses and is important for the evaluation of the integrity of the bowel wall when ischemia or anastomotic dehiscence is suspected. CT with and without contrast would only be indicated when there is benefit from dual- phase imaging. When anastomotic leak is suspected, rectally administered contrast material is important to demonstrate extraluminal extravasation of contrast to confirm the leak, adding an additional finding to other findings of leak: perianastomotic gas, fluid collection, and staple line integrity. Hyman et al [60] reported that CT was superior to fluoroscopic contrast enema at detecting leaks, with a PPV of 89.5% for CT and 40% for contrast enema in 33 patients who developed leaks. Kaur et al [61] showed a 91% sensitivity, 100% specificity, 100% PPV, and 95% NPV for CT in detecting postoperative anastomotic leaks in a retrospective study 170 patients who had undergone a low anterior resection, emphasizing the importance of rectal contrast material to improve confidence in diagnosis.


Anorectal Disease

Anorectal Disease. CT Pelvis CT pelvis may be preferred over CT abdomen and pelvis in specific clinical scenarios when the pelvis alone is the area of clinical concern. To our knowledge there are no studies comparing noncontrast CT with IV contrast- enhanced CT for the detection of postoperative complications. However, IV contrast does improve the detection of abscesses and is important for the evaluation of the integrity of the bowel wall when ischemia or anastomotic dehiscence is suspected. CT with and without IV contrast would only be useful when there is benefit from dual- phase imaging. When anastomotic leak is suspected, rectally administered contrast material is important to demonstrate extraluminal extravasation of contrast to confirm the leak, adding an additional finding to other findings of leak: perianastomotic gas, fluid collection, and staple line integrity. Hyman et al [60] reported that CT was superior to fluoroscopic contrast enema at detecting leaks, with a PPV of 89.5% for CT and 40% for contrast enema in 33 patients who developed leaks. Kaur et al [61] showed a 91% sensitivity, 100% specificity, 100% PPV, and 95% NPV for CT in detecting postoperative anastomotic leaks in a retrospective study of 170 patients who had undergone a low anterior resection, emphasizing the importance of rectal contrast material to improve confidence in diagnosis.


Anorectal Disease

Anorectal Disease. Fluoroscopy Contrast Enema Fluoroscopic contrast enemas performed for the diagnosis of perforation or leak, rectovaginal or rectovesicular fistula, pouchitis, or proctitis can be performed with water-soluble contrast or barium. In general, water-soluble contrast is preferred if a leak or perforation are suspected in order to avoid barium spillage into the peritoneal cavity or extraperitoneal pelvis. Using barium may also interfere with a subsequent CT scan because of the streak artifact that it causes on CT.


Anorectal Disease

Anorectal Disease. Fluoroscopic water-soluble contrast enema is routinely used to evaluate clinically suspected leaks, anastomotic stenoses, fistulas, and sinus tracts. It may be complementary to CT or performed in conjunction with CT. In the study by Tang et al [62], water-soluble contrast enema was performed in 33 of the 66 patients evaluated for pouch disorders and compared with a composite clinical diagnosis. The sensitivity and specificity for the diagnosis of small-bowel and inlet strictures was 80% and 95.7%, and pouch outlet strictures was 0% and 93.5%, respectively. They also found the sensitivity and specificity for the diagnosis of fistula was 33.3% and 96.3%, sinus tract 50% and 100%, pouch leak 50% and 96.8%, respectively [62]. In some institutions, routine water-soluble contrast enema is performed prior to ileostomy takedown. In a study of 42 patients who underwent total proctocolectomy with IPAA, Dolinsky et al [63] showed that 14% of patients had clinically significant occult strictures detected by water- soluble contrast enema prior to ileostomy takedown. On the other hand, others report that routine use of fluoroscopic water-soluble contrast enema in patients with low pelvic anastomoses (ultralow colorectal, coloanal, and IPAA) does not impact ileostomy takedown compared with digital rectal examination and colonoscopy or sigmoidoscopy. In the study by Karsten et al [64], 38 patients were evaluated with fluoroscopic water-soluble contrast enema, which was 100% sensitive and 69% specific for detection of significant pathology, but that pathology was equally detected


Anorectal Disease

Anorectal Disease. on digital rectal examination and endoscopic examinations such that fluoroscopic water-soluble contrast enema could be used selectively on patients with abnormal clinical findings.


Anorectal Disease

Anorectal Disease. The superior contrast resolution of MRI compared with CT makes it an ideal modality for the evaluation of clinically suspected anastomotic or IPAA-related fistulas or sinus tracts. In a study of 44 patients with ulcerative colitis and IPAA with pelvic symptoms, MRI with and without IV gadolinium contrast material detected 23 of 26 fistula for a sensitivity of 88%, specificity of 100%, PPV of 100%, and NPV of 85% [65]. The authors reported that high diagnostic confidence was obtained with the IV gadolinium-enhanced sequence compared with the T2-weighted fat-saturated sequence. MRI was obtained in 23 of the 66 postoperative patients reported by Tang et al [62]. MRI had a sensitivity and specificity for the diagnosis of small-bowel and inlet strictures of 33.3% and 100%, pouch outlet strictures of 0% and 92%, fistula of 57.1% and 88.9%, sinus of 0% and 70.8%, and pouch leak of 0% and 91.7%, respectively.


Anorectal Disease

Anorectal Disease. Radiography Abdomen and Pelvis Radiographs may be helpful in evaluating postoperative patients when there is a suspected bowel obstruction by confirming or excluding small-bowel obstruction. Radiographs may also show free air if there is a suspected postoperative perforation or ectopic air, or bubbly lucencies in the case of abscess, fistula, or sinus tracts that contain air. However, radiographs will frequently be inconclusive and additional imaging will be needed for those patients with abnormal radiographs; additional imaging is often necessary to confirm the suspected diagnosis and to add more specificity to the findings. To our knowledge, there is no recent literature on the use of radiographs in the evaluation of suspected complications after proctectomy with coloanal or colorectal anastomosis and coloproctectomy with IPAA.


Anorectal Disease

Anorectal Disease. Supporting Documents The evidence table, literature search, and appendix for this topic are available at https://acsearch.acr.org/list. The appendix includes the strength of evidence assessment and the final rating round tabulations for each recommendation.


Anorectal Disease

Anorectal Disease. For additional information on the Appropriateness Criteria methodology and other supporting documents go to www.acr.org/ac.


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Anorectal Disease. Anorectal Disease 20. Halligan S, Bartram CI. MR imaging of fistula in ano: are endoanal coils the gold standard? AJR Am J Roentgenol 1998;171:407-12. 21. Zbar AP, Armitage NC. Complex perirectal sepsis: clinical classification and imaging. Tech Coloproctol 2006;10:83-93. 22. Sahni VA, Ahmad R, Burling D. Which method is best for imaging of perianal fistula? Abdom Imaging 2008;33:26-30. 23. Lo Re G, Tudisca C, Vernuccio F, et al. MR imaging of perianal fistulas in Crohn's disease: sensitivity and specificity of STIR sequences. Radiol Med 2016;121:243-51. 24. Yildirim N, Gokalp G, Ozturk E, et al. Ideal combination of MRI sequences for perianal fistula classification and the evaluation of additional findings for readers with varying levels of experience. Diagn Interv Radiol 2012;18:11-9. 25. Visscher AP, Felt-Bersma RJ. Endoanal ultrasound in perianal fistulae and abscesses. Ultrasound Q 2015;31:130-7. 26. Buchanan GN, Bartram CI, Williams AB, Halligan S, Cohen CR. Value of hydrogen peroxide enhancement of three-dimensional endoanal ultrasound in fistula-in-ano. Dis Colon Rectum 2005;48:141-7. 27. Sun Y, Cui LG, Liu JB, Wang JR, Ping H, Chen ZW. Utility of 360 degrees Real-time Endoanal Sonography for Evaluation of Perianal Fistulas. J Ultrasound Med 2018;37:93-98. 28. Buchanan GN, Halligan S, Bartram CI, Williams AB, Tarroni D, Cohen CR. Clinical examination, endosonography, and MR imaging in preoperative assessment of fistula in ano: comparison with outcome-based reference standard. Radiology 2004;233:674-81. 29. Cheong DM, Nogueras JJ, Wexner SD, Jagelman DG. Anal endosonography for recurrent anal fistulas: image enhancement with hydrogen peroxide. Dis Colon Rectum 1993;36:1158-60. 30. West RL, Zimmerman DD, Dwarkasing S, et al. Prospective comparison of hydrogen peroxide-enhanced three- dimensional endoanal ultrasonography and endoanal magnetic resonance imaging of perianal fistulas. Dis Colon Rectum 2003;46:1407-15. 31. Brillantino A, Iacobellis F, Reginelli A, et al. Preoperative assessment of simple and complex anorectal fistulas: Tridimensional endoanal ultrasound? Magnetic resonance? Both? Radiol Med 2019;124:339-49. 32. Senatore PJ, Jr. Anovaginal fistulae. Surg Clin North Am 1994;74:1361-75. 33. Andreani SM, Dang HH, Grondona P, Khan AZ, Edwards DP. Rectovaginal fistula in Crohn's disease. Dis Colon Rectum 2007;50:2215-22. 34. Champagne BJ, McGee MF. Rectovaginal fistula. Surg Clin North Am 2010;90:69-82, Table of Contents. 35. Kuhlman JE, Fishman EK. CT evaluation of enterovaginal and vesicovaginal fistulas. J Comput Assist Tomogr 1990;14:390-4. 36. Giordano P, Drew PJ, Taylor D, Duthie G, Lee PW, Monson JR. Vaginography--investigation of choice for clinically suspected vaginal fistulas. Dis Colon Rectum 1996;39:568-72. 37. Wychulis AR, Pratt JH. Sigmoidovaginal fistulas. A study of 37 cases. Arch Surg 1966;92:520-4. 38. Amendola MA, Agha FP, Dent TL, Amendola BE, Shirazi KK. Detection of occult colovesical fistula by the Bourne test. AJR Am J Roentgenol 1984;142:715-8. 39. Hsieh JH, Chen WS, Jiang JK, Lin TC, Lin JK, Hsu H. Enterovesical fistula: 10 years experience. Zhonghua Yi Xue Za Zhi (Taipei) 1997;59:283-8. 40. Botsikas D, Pluchino N, Kalovidouri A, et al. CT vaginography: a new CT technique for imaging of upper and middle vaginal fistulas. Br J Radiol 2017;90:20160947. 41. Coe FO. Vaginography. Am J Roentgenol Radium Ther Nucl Med 1963;90:721-2. 42. Wolfson JJ. Vaginography for Demonstration of Ureterovaginal, Vesicovaginal, and Rectovaginal Fistulas, with Case Reports. Radiology 1964;83:438-41. 43. Stoker J, Rociu E, Schouten WR, Lameris JS. Anovaginal and rectovaginal fistulas: endoluminal sonography versus endoluminal MR imaging. AJR Am J Roentgenol 2002;178:737-41. 44. Yee LF, Birnbaum EH, Read TE, Kodner IJ, Fleshman JW. Use of endoanal ultrasound in patients with rectovaginal fistulas. Dis Colon Rectum 1999;42:1057-64. 45. Yin HQ, Wang C, Peng X, et al. Clinical value of endoluminal ultrasonography in the diagnosis of rectovaginal fistula. BMC Med Imaging 2016;16:29. 46. Hahnloser D, Pemberton JH, Wolff BG, Larson DR, Crownhart BS, Dozois RR. Results at up to 20 years after ileal pouch-anal anastomosis for chronic ulcerative colitis. Br J Surg 2007;94:333-40. 47. Reber JD, Barlow JM, Lightner AL, et al. J Pouch: Imaging Findings, Surgical Variations, Natural History, and Common Complications. Radiographics 2018;38:1073-88.


Anorectal Disease

Anorectal Disease

Anorectal Disease. Anorectal Disease


Recurrent Lower Urinary Tract Infections in Females. Introduction/Background A urinary tract infection (UTI) is an infection of the urinary system causing an inflammatory response. A UTI occurs when the normal flora of the periurethral area are replaced by uropathogenic bacteria, which ascend, causing bacterial cystitis. Less commonly, this infection ascends to the kidney to cause bacterial pyelonephritis [1]. The overall lifetime risk of UTI for women is >50% [2].


Recurrent Lower Urinary Tract Infections in Females. An uncomplicated UTI is classified as a UTI without structural or functional abnormalities of the urinary tract and without relevant comorbidities. It should be noted that although uncomplicated UTI includes both lower tract infection (cystitis) and upper tract infection (pyelonephritis), repeated pyelonephritis should prompt consideration of a complicated etiology [1]. Complicated UTIs are those occurring in patients with underlying structural or medical problems [3,4]. Anatomical abnormalities include cystoceles, bladder or urethral diverticula, fistulae, indwelling catheters, urinary tract obstruction and underlying conditions such as voiding dysfunction, pregnancy, diabetes, and immunosuppression. Other documented risk factors include prior urinary tract surgery or trauma, gross hematuria after infection resolution, urea-splitting bacteria on culture, prior abdominopelvic malignancy, prior urinary tract calculi, prior diverticulitis, symptoms of pneumaturia, fecaluria, or repeated pyelonephritis.


Recurrent Lower Urinary Tract Infections in Females. In the nonobstructed, nonpregnant woman, uncomplicated UTI is usually treated empirically and responds to appropriate antimicrobial therapy [2,5]. A UTI is considered recurrent when it follows the complete clinical resolution of a previous UTI [6]. Recurrent lower UTIs are usually defined as at least three episodes of infection within the preceding 12 months [3]. Recurrent UTIs involve reinfection from a source outside of the urinary tract or from bacterial persistence [1-3]. In most cases, such infections are the result of sexual habits and hygiene (eg, women who are sexually active, especially those using diaphragms and/or spermatocides) [3,7]. Although antibiotic prophylaxis effectively limits UTI recurrence, it increases the risk of antibiotic resistance for both the causative microorganisms and the indigenous flora and risks adverse effects. It therefore should be approached judiciously. Before considering antibiotic prophylaxis for recurrent UTIs, self-care measures should be advised, including ensuring adequate hydration to promote more frequent urination, encouraging urge-initiated voiding and post-coital voiding, the avoidance of spermicidal-containing contraceptives, and, for postmenopausal women with risk factors such as atrophic vaginitis, the prescription of topical vaginal estrogens, as appropriate [8,9]. A clean-catch or catheterized specimen for culture typically reveals >100,000 organisms per milliliter of urine. E. coli is the most common organism in all patient groups, causing approximately 75% of recurrent UTIs, with most other infections caused by E. faecalis, Proteus mirabilis, Klebsiella, or S. saprophyticus particularly in patients with risk factors for complicated UTIs [6,10-12]. Postmenopausal women are at increased risk for recurrent UTI in the presence of urinary incontinence, cystocele, or high postvoid residuals of urine [13,14].


Recurrent Lower Urinary Tract Infections in Females. Women who have three or more symptomatic infections over a 12-month period may benefit from prophylaxis [3,4,7]. Imaging is of low yield in patients without underlying risk factors, less than two episodes per year on average, and who respond promptly to appropriate therapy (see Appendix 1) [1,7,15,16]. Current clinical guidelines indicate that imaging should not be routinely obtained in the index patient presenting with recurrent UTIs because


Recurrent Lower Urinary Tract Infections in Females. aThe University of Texas MD Anderson Cancer Center, Houston, Texas. bPanel Chair, University of Chicago, Chicago, Illinois. cPanel Vice-Chair, Duke University Medical Center, Durham, North Carolina. dMemorial Sloan Kettering Cancer Center, New York, New York. eMayo Clinic, Jacksonville, Florida. fMcGill University, Montreal, Quebec, Canada. gMayo Clinic, Rochester, Minnesota. hUrology Clinics of North Texas, Dallas, Texas; American Urological Association. iUniversity of Pennsylvania School of Medicine, Philadelphia, Pennsylvania; American Society of Nephrology. jUniversity of Wisconsin, Madison, Wisconsin. kUPMC, Pittsburgh, Pennsylvania; American Urological Association. lStanford University Medical Center, Stanford, California. mOttawa Hospital Research Institute and the Department of Radiology, The University of Ottawa, Ottawa, Ontario, Canada. nEmory University Hospital, Atlanta, Georgia. oNational Institutes of Health, Bethesda, Maryland. pSpecialty Chair, University of Alabama at Birmingham, Birmingham, Alabama.


Recurrent Lower Urinary Tract Infections in Females. The American College of Radiology seeks and encourages collaboration with other organizations on the development of the ACR Appropriateness Criteria through society representation on expert panels. Participation by representatives from collaborating societies on the expert panel does not necessarily imply individual or society endorsement of the final document.


Recurrent Lower Urinary Tract Infections in Females. Reprint requests to: publications@acr.org