Dialysis Fistula Malfunction

Dialysis Fistula Malfunction. MRV Extremity Area of Interest Without IV Contrast There is no identifiable relevant literature to support the use of MRV extremity without IV contrast in evaluation of suspected vascular steal.


Dialysis Fistula Malfunction

Dialysis Fistula Malfunction. Variant 12: Suspected vascular steal syndrome (upper or lower extremity), suggested by cardiac failure or ischemic symptoms. Treatment and procedures. Fluoroscopy Fistulography Hemodialysis Access with Intervention While surgical management for vascular steal syndrome is often considered, fluoroscopic fistulography of the hemodialysis access with endovascular intervention may have a limited role in treatment, including elimination of a culprit arterial stenosis by angioplasty or stenting. In cases of DASS with stenosis of the inflow artery supplying the hemodialysis access and the extremity, endovascular angioplasty with or without stent placement has been proposed as a potential treatment [140]. Endovascular occlusion of hemodialysis access using vascular plugs has also been suggested as a potential treatment for patients with DASS as an alternative to surgical ligation [128].


Dialysis Fistula Malfunction

Dialysis Fistula Malfunction. In cases where surgical ligation may be challenging due to ulcerations or marked edema or swelling of the extremity, surgery may be delayed due to challenging patient comorbidities [128]. In such cases, an endovascular approach may be necessary to manage the problem. Gumus et al [128] reported 21 patients who underwent endovascular occlusion of their native fistulas. Of the studied patients, 2 patients had hyperdynamic heart failure, 2 exhibited DASS and 5 patients had findings of critical hand ischemia with a nonhealing ulcer or necrosis. Successful embolization of all fistulas using AMPLATZER vascular plugs were performed with no immediate or delayed complications with a mean follow-up of 13.5 months.


Dialysis Fistula Malfunction

Dialysis Fistula Malfunction

Dialysis Fistula Malfunction. Dialysis Fistula Malfunction


Dialysis Fistula Malfunction

Dialysis Fistula Malfunction. In forearm and wrist fistulae, cases of DASS occur at a rate of 1%, and is referred to as palmar arch steal syndrome. While digital revascularization with interval ligation (DRIL) is the most accepted technique with the highest success of correcting signs of steal phenomenon while preserving access patency, it is technically difficult and has a small chance of success when employed in wrist fistulae. This is due to the notably reduced diameter of the associated arteries that may also contain calcific disease in at-risk persons [134]. As such, in forearm AVF, surgical ligation or endovascular embolization of the radial artery distal to the anastomosis are helpful treatment options. Miller et al reported endovascular coil embolization in 10 patients while surgical ligation was conducted in 5 patients. Improvement in symptoms was noted in each of the patients in the endovascular group versus 3 patients in the group which underwent ligation [141].


Dialysis Fistula Malfunction

Dialysis Fistula Malfunction. Advantages of endovascular management include its minimally invasive nature, its ability to be performed concomitantly with diagnostic angiography, and the capacity for performing occlusion of both the distal radial artery as well as any other culprit branches. The ability to perform angioplasty on additional stenoses augments blood flow to the fistula and hand. Endovascular dilation is achievable in the palmar arch arteries and distal forearm where surgical revascularization is routinely not possible.


Dialysis Fistula Malfunction

Dialysis Fistula Malfunction. Distal radial artery embolization combined with recanalization and angioplasty of any present ulnar artery stenoses and occlusions may provide equivalent results with the DRIL operation, which is regarded as the most efficient and effective treatment option for correcting the hemodynamics in DASS. While coil occlusion of the distal radial artery preempts the steal phenomenon in a manner comparable to that of interval ligation, the presence of a normal or effectively angioplastied ulnar artery will offer distal blood flow with superior flows [134].


Dialysis Fistula Malfunction

Dialysis Fistula Malfunction. Surgical Consultation Surgical management in the setting of DASS or ischemic steal syndrome is a useful treatment option [142-146]. Surgical management of moderate-to-severe ischemic steal syndrome may be divided into 3 general categories which includes ligation (banding and plication), rerouting of arterial inflow, and restriction of flow. Surgical techniques for the treatment of DASS include DRIL, which involves ligation of the brachial artery and placement of a vein bypass to the distal brachial artery, revision using distal inflow, distal radial artery ligation, proximalization of arterial inflow, and banding [144,145].


Dialysis Fistula Malfunction

Dialysis Fistula Malfunction. Leake et al [145] evaluation of surgical management of DASS in 175 AV fistulas (80%), 41 upper extremity prosthetic grafts (19%), and 2 thigh grafts (1%) demonstrated that DRIL and ligation were offered to patients with the highest severity of symptoms. When compared to ligation, DRIL is equivalent in symptom resolution, with no associated increase in complications, and offers fistula preservation. When compared to banding, DRIL achieved a higher degree of fistula preservation and with a lower incidence of complications. They concluded that DRIL ought to be the preferred surgical management of DASS in patients with a functioning autologous fistula who are surgical candidates. Gupta et al [147] similarly reported their analysis of the outcomes of management of patients with ischemic steal syndrome. They reported that DRIL was the most frequently selected option for late interventions (41%). Banding was reported to have a high failure rate (62%) and was associated with the most common cause for reintervention (8 of 11, 73%), DRIL boasted superior success rates to banding (P < .05).


Dialysis Fistula Malfunction

Dialysis Fistula Malfunction. While surgical treatment options are preferred in upper arm fistulae, endovascular treatment options may be more suited for revascularization of fistulae in the forearm secondary to the diminutive caliber of target vessels, the often- severe calcifications in at-risk persons, and thus the low chance of success [134]. However, surgery consultation is still recommended when vascular steal syndrome is suspected.


Dialysis Fistula Malfunction

Dialysis Fistula Malfunction. Placement of a New Tunneled Dialysis Catheter The placement of a new tunneled dialysis catheter may be a bridging therapy, allowing for hemodialysis access while a patient undergoes surgical or radiologic evaluation, in the setting of suspected vascular steal syndrome, suggested by cardiac failure or ischemic symptoms. Given associated increased risks of infection, higher mortality, and lower patency when compared to AVF and AVG, tunneled dialysis catheters should be avoided if possible or considered a temporizing measure until other hemodialysis access is available [108].


Dialysis Fistula Malfunction

Dialysis Fistula Malfunction


Dialysis Fistula Malfunction

Dialysis Fistula Malfunction. 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.


Dialysis Fistula Malfunction

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


Imaging After Shoulder Arthroplasty PCAs. Introduction/Background There has been a rapid increase in the number of shoulder arthroplasties, including partial or complete humeral head resurfacing, hemiarthroplasty, total shoulder arthroplasty, and reverse total shoulder arthroplasty, performed in the United States over the past 2 decades [1]. The most recent published estimates have reported a 2.5-fold increase in the number of shoulder arthroplasties performed between 1998 and 2008, from 19,000 to 47,000 [1,2]. Overall, total shoulder arthroplasties are the most common type, having surpassed hemiarthroplasties in the last decade [1].


Imaging After Shoulder Arthroplasty PCAs. Most shoulder arthroplasties are performed for degenerative conditions. Humeral head resurfacing is indicated in patients with humeral head osteonecrosis, large Hill-Sachs deformity, or focal osteoarthrosis. Hemiarthroplasties are typically performed in patients with osteoarthrosis limited to the humeral head or in patients with comminuted humeral head fractures. Hemiarthroplasties are also recommended in patients with deficient glenoid bone stock and in patients with greater preoperative comorbidities because they require a shorter intraoperative time compared with total shoulder arthroplasty. Presently, total shoulder arthroplasty is recommended over hemiarthroplasty for advanced shoulder osteoarthrosis because of its superior clinical outcome.


Imaging After Shoulder Arthroplasty PCAs. Reverse shoulder arthroplasties were first introduced in 1987 as a treatment option for patients with a deficient rotator cuff and have been used as a salvage procedure for patients with failed total shoulder arthroplasties [3,4]. Reverse shoulder arthroplasties are constructed differently from total shoulder arthroplasties to compensate for the lack of stabilization related to the deficient rotator cuff. The glenoid component is a round metal ball (referred to as the glenosphere) attached to a baseplate along the glenoid surface, and the humeral component has a cup-shaped articular margin secured by a metal stem [4]. The construct moves the center of rotation medial and distal, which allows the deltoid muscle to serve as a main stabilizer of the arthroplasty and joint [4]. Additionally, the more medial and distal center of rotation decreases the risk of glenoid loosening [4,5].


Imaging After Shoulder Arthroplasty PCAs. Symptoms related to postoperative difficulties include activity-related pain, decreased range of motion, and apprehension. Some patients report immediate and persistent dissatisfaction, although others report a symptom-free postoperative period followed by increasing pain and decreasing shoulder function and mobility [10].


Imaging After Shoulder Arthroplasty PCAs. Imaging can play an important role in diagnosing postoperative complications of shoulder arthroplasties. The imaging algorithm should always begin with an assessment of the hardware components, alignment, and


Imaging After Shoulder Arthroplasty PCAs. avRad, Eden Prairie, Minnesota. bUT Health San Antonio, San Antonio, Texas. cPanel Chair, Mayo Clinic Arizona, Phoenix, Arizona. dJames J. Peters VA Medical Center, Bronx, New York; American Academy of Orthopaedic Surgeons. eHospital for Special Surgery, New York, New York. fThomas Jefferson University Hospital, Philadelphia, Pennsylvania. gUniversity of Virginia Health System, Charlottesville, Virginia. hDuke University Medical Center, Durham, North Carolina. iUniversity of Missouri Health Care, Columbia, Missouri. jCleveland Clinic, Cleveland, Ohio. kNorthwestern Memorial Hospital, Chicago, Illinois; American College of Physicians. lPenn State Milton S. Hershey Medical Center, Hershey, Pennsylvania and Uniformed Services University of the Health Sciences, Bethesda, Maryland. mThe Ohio State University Wexner Medical Center, Columbus, Ohio. nSpecialty Chair, Mayo Clinic, Phoenix, Arizona. The American College of Radiology seeks and encourages collaboration with other organizations on the development of the ACR Appropriateness Criteria through representation of such organizations on expert panels. Participation on the expert panel does not necessarily imply endorsement of the final document by individual contributors or their respective organization.


Imaging After Shoulder Arthroplasty PCAs. Reprint requests to: publications@acr.org


Imaging After Shoulder Arthroplasty

Imaging After Shoulder Arthroplasty PCAs. Imaging After Shoulder Arthroplasty


Imaging After Shoulder Arthroplasty PCAs. surrounding osseous and soft-tissue structures. The selection of the next imaging modality depends on several factors, including findings on the initial imaging study, clinical suspicion of an osseous versus soft-tissue injury, or clinical suspicion of infection.


Imaging After Shoulder Arthroplasty PCAs. Special Imaging Considerations Arthrography Arthrography, using only radiographic or fluoroscopic images, had previously been utilized for detecting rotator cuff tears in the setting of shoulder arthroplasty. Because of its inability to assess muscle quality, gradation of partial tearing, and differentiate between the torn rotator cuff tendons, conventional radiographic arthrography has mostly been supplanted by cross-sectional imaging techniques such as CT arthrography, MR arthrography, and ultrasound (US).


Imaging After Shoulder Arthroplasty PCAs. Nuclear Medicine The use of nuclear medicine in the evaluation of complications after arthroplasty has been limited to the evaluation of hip and knee arthroplasties. Because of limited literature on shoulder arthroplasties, these same physiologic principles can be applied to shoulder arthroplasties, and radionuclide imaging is not limited by metallic hardware [11].


Imaging After Shoulder Arthroplasty PCAs. Tc-99m-methylene diphosphonate (MDP) bone scans are useful in assessing shoulder arthroplasties, especially with normal radiographs and persistent concern for aseptic loosening, osteomyelitis, or periprosthetic fractures. Unfortunately, the specificity of bone scans is low, and new bone formation can also be seen in normal or abnormal postoperative bony remodeling and neuropathic arthropathy in addition to acute fractures, periprosthetic infection, or aseptic prosthetic loosening.


Imaging After Shoulder Arthroplasty PCAs. Typical bone scans are either a single or a 3-phase study. The standard single-phase bone scan involves imaging 2 to 3 hours after MDP administration. The 3-phase bone scan consists of a 1-minute radionuclide angiogram followed by immediate blood pool images and 2- to 3-hour delayed views. The 3-phase scan can be helpful in the assessment of acute fracture and differentiating acute osteomyelitis from cellulitis.


Imaging After Shoulder Arthroplasty PCAs. A positive 3-phase bone scan is often seen in neuropathic arthropathy. The use of radiolabeled white blood cells (WBC) with In-111 in conjunction with bone marrow imaging, utilizing Tc-99m sulfur colloid, can help to differentiate neuropathic reactive bone marrow from acute osteomyelitis. Serial bone scans can also assist in assessing postoperative bone remodeling and periprosthetic fracture from aseptic periprosthetic loosening.


Imaging After Shoulder Arthroplasty PCAs. The value of WBC and marrow imaging is not only to differentiate neuropathic arthropathy from acute osteomyelitis but also to differentiate aseptic loosening from acute osteomyelitis. Like neuropathic arthropathy, aseptic loosening will demonstrate spatially congruent WBC and marrow activity, consistent with reactive or hematopoietically active marrow.


Imaging After Shoulder Arthroplasty PCAs. Imaging After Shoulder Arthroplasty Discussion of Procedures by Variant Variant 1: Routine follow-up of the asymptomatic patient with a primary shoulder arthroplasty. 3-Phase Bone Scan with SPECT or SPECT/CT Shoulder A 3-phase bone scan is not typically ordered for evaluation of the asymptomatic patient. Although, single-photon emission computed tomography (SPECT)/CT can assess the primary osseointegration of a stemless shoulder prosthesis in the recent postoperative state [12].


Imaging After Shoulder Arthroplasty PCAs. Bone Scan Shoulder There is no relevant literature to support the use of a bone scan of the shoulder in the follow-up of the asymptomatic patient with a primary shoulder arthroplasty.


Imaging After Shoulder Arthroplasty PCAs. CT Shoulder CT examinations are not typically ordered for evaluation of the asymptomatic patient.


Imaging After Shoulder Arthroplasty PCAs. Fluoride PET/CT Skull Base to Mid-Thigh There is no relevant literature to support the use of fluoride PET/CT skull base to mid-thigh in the follow-up of the asymptomatic patient with a primary shoulder arthroplasty.


Imaging After Shoulder Arthroplasty PCAs. MRI Shoulder MRI examinations are not typically ordered for evaluation of the asymptomatic patient.


Imaging After Shoulder Arthroplasty PCAs. Radiographs are also typically ordered for yearly follow-up examinations to assess interval changes in the bone surrounding the prosthesis [16]. The presence of scapular notching on postoperative radiographs of reverse total shoulder prostheses has been associated with poor clinical outcomes [17]. The risk for loosening increases over time, with notable radiographic changes associated with loosening found at least 5 years after surgery, most commonly involving the glenoid component [18]. Late complications requiring revision surgery, such as loosening, infection, and fracture, occurring up to 15 years postoperatively, suggests the need for long-term radiographic follow-up when these complications are asymptomatic or their outcome can be affected by early detection on radiographs [10].


Imaging After Shoulder Arthroplasty PCAs. US Shoulder US examinations are not typically ordered for evaluation of the asymptomatic patient.


Imaging After Shoulder Arthroplasty PCAs. 3-Phase Bone Scan with SPECT or SPECT/CT Shoulder There is no relevant literature to support the use of a 3-phase bone scan with SPECT or SPECT/CT as a first-line imaging modality in the acutely symptomatic patient with a primary shoulder arthroplasty. Similar to bone scans, a 3-phase bone scan is highly sensitive for the detection of periprosthetic fractures but suffers from low specificity.


Imaging After Shoulder Arthroplasty PCAs. Imaging After Shoulder Arthroplasty Acute periprosthetic fractures are often 3-phase bone scan positive and demonstrate focal increased activity at the fracture site, which decreases over time, corresponding to fracture healing. Fracture hyperemia also typically resolves with the acute/subacute phases. The addition of SPECT or SPECT/CT improves diagnosis by allowing more accurate anatomical localization of new bone formation [20]. The specificity of Tc-99m bone scans for periprosthetic fractures increases in older prostheses once postoperative remodeling has decreased.


Imaging After Shoulder Arthroplasty PCAs. Bone Scan Shoulder There is no relevant literature to support the use of a bone scan as a first-line imaging modality in the acutely symptomatic patient with a primary shoulder arthroplasty. Tc-99m single- and 3-phase bone scans are very sensitive but with low specificity in the diagnosis of post arthroplasty fractures, and imaging findings can overlap with other abnormalities such as loosening and infection [21]. Without a radionuclide angiogram and blood pool phase, the single-phase bone scan will not depict the acute peri fracture hyperemia. Acute periprosthetic fractures are often 3- phase bone scan positive and demonstrate focal increased activity at the fracture site, which decreases over time, corresponding to fracture healing. Fracture hyperemia also typically resolves with the acute/subacute phases. Uncomplicated fracture healing may take up to 2 years before a bone scan normalizes [21,22]. In addition, increased bone uptake can be seen at the site of arthroplasty, related to postoperative bone remodeling for up to 1 year following surgery, which can further complicate matters [21]. The specificity of Tc-99m bone scan imaging for periprosthetic fracture increases in older prostheses once the postoperative remodeling has decreased and stabilized.


Imaging After Shoulder Arthroplasty PCAs. CT Shoulder CT is not typically ordered for the initial evaluation of a symptomatic shoulder arthroplasty. CT with metal reduction protocol can be subsequently used to detect loosening and to further delineate a periprosthetic fracture seen on radiographs in terms of degree of displacement, extent, and comminution. CT can also be used when a fracture is suspected clinically but the radiographs are negative such as in the setting of a suspected acromial stress fracture in the patient with a reverse total shoulder arthroplasty [23].


Imaging After Shoulder Arthroplasty PCAs. Fluoride PET/CT Skull Base to Mid-Thigh There is no relevant literature to support the use of fluoride PET/CT as a first-line imaging modality in the acutely symptomatic patient with a primary shoulder arthroplasty.


Imaging After Shoulder Arthroplasty PCAs. MRI Shoulder MRI is not typically ordered for the initial evaluation of a symptomatic shoulder arthroplasty but, in the opinion of the committee, can play a contributory role when fractures are occult on radiographs and/or CT examinations. MRI can identify the location of the fracture by detecting associated marrow edema and, not infrequently, an associated fracture line. MRI also well delineates soft-tissue abnormalities in the setting of infection and rotator cuff injury.


Imaging After Shoulder Arthroplasty PCAs. Radiography Shoulder Radiography is the first and main imaging modality utilized in the evaluation of both the symptomatic and asymptomatic shoulder arthroplasty [10,13]. Findings on radiographs can be used to diagnose and guide further assessment of both osseous and high-grade rotator cuff abnormalities. Radiographs are particularly helpful for the detection of scapular fractures that can occur with relatively minor trauma in patients with reverse shoulder prostheses [24].


Imaging After Shoulder Arthroplasty PCAs. US Shoulder US examinations are not typically ordered as a first-line study for evaluation of pain in the setting of shoulder arthroplasty. Nevertheless, US provides assessment of the rotator cuff integrity and is capable of detecting cortical discontinuity and step-off in the setting of a fracture after shoulder arthroplasty [25].


Imaging After Shoulder Arthroplasty PCAs. Variant 3: Symptomatic patient with a primary shoulder arthroplasty, infection not excluded. Additional imaging following radiographs. Infection, including osteomyelitis and septic arthritis, after total shoulder arthroplasty is an uncommon albeit potentially devastating complication, with a prevalence of 0.7% to 2.9%. Infection is more common in males and a younger age group [3,26,27]. A 97% infection-free rate at 20 years has been reported [28]. Predisposing underlying conditions may include rheumatoid arthritis, corticosteroid use, diabetes, repeated intra-articular steroid injections, and prior shoulder surgery [26].


Imaging After Shoulder Arthroplasty PCAs. Infection rates are higher in the setting of reverse total shoulder arthroplasties, with a range of 0.8% to 10% [29]. Proposed causes for this higher prevalence include longer procedural time and steeper learning curve to perform the surgery, large dead space, multiple previous operations, and advanced patient age [29].


Imaging After Shoulder Arthroplasty PCAs. Imaging After Shoulder Arthroplasty 3-Phase Bone Scan and WBC Scan and Sulfur Colloid Scan Shoulder For infection imaging, In-111-labeled WBC with a Tc-99m sulfur colloid bone marrow study is a sensitive and specific test for acute osteomyelitis. An isolated In-111 WBC study is a sensitive but nonspecific technique for the evaluation of acute neutrophilic dominant periprosthetic infection [11]. Its specificity can be increased when interpreted in conjunction with a Tc-99m sulfur colloid study or, less optimally, a bone scan, which may not be indicated if both In-111 WBC and sulfur colloid studies have been performed [11,30].


Imaging After Shoulder Arthroplasty PCAs. Tc-99m 3-phase bone scan is a highly sensitive modality for identifying osteolysis and increased osteoblastic activity from postoperative bony remodeling, aseptic loosening, acute osteomyelitis, and periprosthetic fractures. The specificity of bone scans increases in older prostheses once postoperative remodeling has stabilized. Concordant increased labeled WBC and marrow activity is consistent with reactive marrow seen in postoperative change, aseptic loosening, and fractures. Postoperative change and fracture healing tend to decrease over time. Fracture confirmation can also be identified with anatomic imaging (eg, radiographs, CT with metal artifact reduction techniques). Normal uncomplicated postoperative change tends to decrease over time and up to 2 years or longer after surgery [21,22], whereas aseptic loosening generally tends to progress. Discordant activity of increased labeled WBC and a photopenic bone marrow is consistent with acute osteomyelitis.


Imaging After Shoulder Arthroplasty PCAs. 3-Phase Bone Scan and WBC Scan and Sulfur Colloid Scan with SPECT or SPECT/CT Shoulder The use of nuclear imaging for the evaluation of periprosthetic infection has been limited to the evaluation of hip and knee arthroplasties, but various clinical studies anecdotally suggest utilizing this modality in shoulder arthroplasties [30].


Imaging After Shoulder Arthroplasty PCAs. Tc-99m 3-phase bone scan is a highly sensitive modality for the detection of acute osteomyelitis in the setting of normal radiographs but remains low in specificity because the imaging findings can overlap with other abnormalities such as mechanical loosening and osteolysis [30]. In addition, increased bone uptake can be seen at the site of arthroplasty, related to postoperative bone remodeling, for up to 1 year following surgery [30]. A bone scan is also limited in its ability to assess the periprosthetic soft tissues for the presence of an abscess.


Imaging After Shoulder Arthroplasty PCAs. The addition of a bone scan SPECT/CT improves contrast resolution and anatomic localization of radiopharmaceutical uptake and provides a limited CT in the area of concern. A blood pool SPECT/CT over the targeted clinical area can be obtained immediately after the static blood pool images and further localizes foci of hyperemia [31-33]. At 2 to 3 hours after radiopharmaceutical administration and the standard bone scan images, a second SPECT/CT over the area(s) of interest can localize new bone formation [30] but remains nonspecific. A positive 3-phase bone scan can be seen in periprosthetic infection, periprosthetic fracture, and in the early postoperative state. Postoperative change and fracture healing tend to decrease over time. Fracture confirmation can also be identified with anatomic imaging (eg, radiographs, CT with metal artifact reduction techniques). Normal uncomplicated postoperative change tends to decrease over time and up to 2 years or longer after surgery [21,22], whereas aseptic loosening generally tends to progress. The specificity of bone scans increases in older prostheses once the postoperative remodeling has stabilized.


Imaging After Shoulder Arthroplasty PCAs. The addition of SPECT/CT with the In-111 WBC and sulfur colloid scans increases contrast resolution and anatomic localization of radiopharmaceutical activity. Utilizing subtraction imaging on the SPECT/CT studies (subtracting the sulfur colloid from WBC images) can identify whether an area of concern on the bone scan is concordant with similar increased WBC and marrow activity (reactive marrow) or discordant (WBC activity with absent sulfur colloid activity), the latter consistent with an acute pyogenic process/osteomyelitis.


Imaging After Shoulder Arthroplasty PCAs. 3-Phase Bone Scan with SPECT or SPECT/CT Shoulder The use of nuclear imaging for the evaluation of periprosthetic infection has been limited to the evaluation of hip and knee arthroplasties, but various clinical studies anecdotally suggest utilizing this modality in shoulder arthroplasties [30].


Imaging After Shoulder Arthroplasty PCAs. Imaging After Shoulder Arthroplasty Tc-99m 3-phase bone scan is a highly sensitive modality for the detection of acute osteomyelitis in the setting of normal radiographs but remains low in specificity as the imaging findings can overlap with other abnormalities such as mechanical loosening and osteolysis [30]. In addition, increased bone uptake can be seen at the site of arthroplasty, related to postoperative bone remodeling, for up to 1 year following surgery [30]. A bone scan is also limited in its ability to assess the periprosthetic soft tissues for the presence of an abscess.


Imaging After Shoulder Arthroplasty PCAs. The addition of SPECT or SPECT/CT improves anatomic localization of new bone formation [20] but remains nonspecific. A positive 3-phase bone scan can be seen in periprosthetic infection, periprosthetic fracture, and in the early postoperative state. Postoperative change and fracture healing tend to decrease over time. Fracture confirmation can also be identified with anatomic imaging (eg, radiographs, CT with metal artifact reduction techniques). Normal uncomplicated postoperative change tends to decrease over time and up to 2 years or longer after surgery [21,22], whereas aseptic loosening generally tends to progress. The specificity of bone scans increases in older prostheses once the postoperative remodeling has stabilized.


Imaging After Shoulder Arthroplasty PCAs. Image-Guided Aspiration Shoulder Aspiration of the shoulder should be performed when there is suspicion for an infected shoulder arthroplasty clinically, with or without radiographic evidence of infection, to avoid the destructive soft-tissue and bone changes that can result from an untreated infection. Imaging-guided aspiration procedures provide a minimally invasive means to sample fluid from the joint suspected of infection [34,35]. Shoulder joint aspiration has been shown to have a sensitivity of 33% and specificity of 98% [36]. Shoulder aspiration can be completed with the use of fluoroscopy, US, and CT guidance. MR guidance is possible but rarely utilized. Arthrography can be performed along with aspiration, when done under fluoroscopy and CT, to confirm the intra-articular origin of any aspirated fluid as well as to assess for any extension of the infectious process into adjacent bursae, sinus tracts, and abscesses [34].


Imaging After Shoulder Arthroplasty PCAs. Bone Scan Shoulder The use of nuclear imaging for the evaluation of periprosthetic infection has been limited to the evaluation of hip and knee arthroplasties, but various clinical studies anecdotally suggest utilizing this modality in shoulder arthroplasties [30].


Imaging After Shoulder Arthroplasty PCAs. The standard Tc-99m bone scan is a sensitive modality for the identification of abnormal bone in acute osteomyelitis, particularly in the setting of normal radiographs. However, the 3-phase bone scan is often preferred to assess for associated hyperemia in acute fracture and acute osteomyelitis. Bone scans remain low in specificity as the imaging findings can overlap with other abnormalities, such as mechanical loosening with osteolysis [30], periprosthetic fracture, and postarthroplasty bone remodeling, which can be seen up to 1 year following surgery [30]. Postoperative change and fracture healing tend to decrease over time. Fracture confirmation can also be identified with anatomic imaging (eg, radiographs, CT with metal artifact reduction techniques). Normal uncomplicated postoperative change tends to decrease over time and up to 2 years or longer after surgery [21,22], whereas aseptic loosening generally tends to progress. The specificity of bone scans for periprosthetic fracture or infection increases in older prostheses once the postoperative remodeling has stabilized.


Imaging After Shoulder Arthroplasty PCAs. CT Shoulder CT with metal reduction protocols can elucidate the findings seen on radiographs and can further narrow the differential diagnosis in a patient suspected of periprosthetic infection as well as assist in preoperative planning [3]. CT may play a more important role after removal of the hardware and debridement in a patient with infection because it can help quantify the amount of remaining bone that can be used for revision arthroplasty [3]. CT can also be used to evaluate the surrounding soft tissues for infection and to aid in planning before image-guided joint aspiration. Administration of intravenous (IV) contrast improves the evaluation of adjacent soft-tissue fluid collections/abscesses and sinus tracts.


Imaging After Shoulder Arthroplasty PCAs. Fluoride PET/CT Skull Base to Mid-Thigh There is no relevant literature to support the use of fluoride PET/CT for the next imaging study of a symptomatic patient with a primary shoulder arthroplasty when infection has been not excluded.


Imaging After Shoulder Arthroplasty PCAs. MRI Shoulder MRI with metal reduction protocols can play a useful role in the diagnosis [37,38] and assessment of periprosthetic infection, particularly when other modalities fail to confirm the clinical suspicion of infection. MRI can demonstrate osseous and soft-tissue abnormalities associated with periprosthetic infection [28,39]. MRI can depict marrow edema suggestive of osteomyelitis. It can depict bony destruction, which can be difficult to note on radiographs,


Imaging After Shoulder Arthroplasty PCAs. Imaging After Shoulder Arthroplasty related to osteomyelitis. MRI can also demonstrate joint effusions, adjacent soft-tissue edema, and fluid loculations suggestive of abscesses. Administration of IV contrast improves the evaluation of adjacent soft-tissue fluid collections/abscesses and sinus tracts.


Imaging After Shoulder Arthroplasty PCAs. US Shoulder US examinations are increasingly being ordered for evaluation of periprosthetic infection in the setting of shoulder arthroplasty to evaluate for joint effusion and surrounding soft-tissue infection. US may be of use for the evaluation of a joint effusion, bursal distention, and the surrounding soft-tissues for signs of infection including abscesses [40- 42], which need aspiration and testing to determine the presence of infection and identification of the underlying microorganism. US is useful to evaluate the surrounding soft tissues for infection and to aid in planning before image-guided joint aspiration in order to avoid seeding of a sterile joint effusion from overlying soft-tissue infection.


Imaging After Shoulder Arthroplasty PCAs. WBC Scan and Sulfur Colloid Scan Shoulder For infection imaging, In-111 WBC imaging in conjunction with Tc-99m sulfur colloid marrow imaging is a sensitive and specific test. An isolated In-111-labeled WBC study is a sensitive but nonspecific technique for the evaluation of acute neutrophilic dominant periprosthetic infection [11]. Its specificity can be increased when interpreted alongside Tc-99m sulfur colloid imaging or, less optimally, bone scan imaging; the latter may not be indicated if both In-111 WBC and sulfur colloid imaging have been performed [11,21,30].


Imaging After Shoulder Arthroplasty PCAs. Variant 4: Symptomatic patient with a primary shoulder arthroplasty, infection excluded. Suspected loosening. Additional imaging following radiographs. Aseptic loosening, also referred to as mechanical loosening, is used to describe a hardware abnormality that results from a noninfectious etiology. One of the most common causes of aseptic loosening is osteolysis, a foreign-body response to debris that results from wear and breakdown of the hardware components, such as the acetabular polyethylene liner, cement, and/or metallic elements. Osteolysis can cause extensive, often asymptomatic, bone loss [43-45]. Although this process has been described extensively in the literature for hip arthroplasty, the literature on the topic is sparse in patients with shoulder arthroplasties [23,46].


Imaging After Shoulder Arthroplasty PCAs. 3-Phase Bone Scan with SPECT or SPECT/CT Shoulder Tc-99m 3-phase bone scan is a highly sensitive modality for the detection of acute osteomyelitis in the setting of normal radiographs but remains low in specificity because the imaging findings can overlap with other abnormalities, such as mechanical loosening with osteolysis and periprosthestic fracture [30]. In addition, increased bone uptake can be identified at the site of arthroplasty, related to postoperative bone remodeling, and seen for up to 1 year following surgery [30].


Imaging After Shoulder Arthroplasty PCAs. The addition of SPECT or SPECT/CT improves anatomic localization of active bone remodeling [20], however, remains nonspecific. A positive 3-phase bone scan can be seen in the early postoperative state, periprosthetic fracture, aseptic prosthetic loosening, and periprosthetic infection. Postoperative change and fracture healing tend to decrease over time. Fracture confirmation can also be identified with anatomic imaging (eg, radiographs, CT with metal artifact reduction techniques). SPECT/CT also has the potential to differentiate symptomatic from asymptomatic scapular notching associated with reverse shoulder prostheses [30]. Normal uncomplicated postoperative change tends to decrease over time and up to 2 years or longer after surgery [21,22], whereas aseptic loosening generally tends to progress. The specificity of bone scans for periprosthetic complications increases in older prostheses once the postoperative remodeling has stabilized.


Imaging After Shoulder Arthroplasty PCAs. Bone Scan Shoulder Tc-99m single-phase bone scan imaging is a sensitive modality for the diagnosis of loosening in the setting of normal radiographs but remains low in specificity because the imaging findings can overlap with other abnormalities such as postoperative bone remodeling, periprosthetic fracture, and infection [30]. Normal uncomplicated increased periprosthetic uptake related to postoperative bone remodeling tends to decrease over time and up 2 years or longer after surgery [21,30], whereas aseptic loosening generally tends to progress. The specificity of bone scans for periprosthetic fracture, loosening, or infection increases in older prostheses once the postoperative remodeling has stabilized.


Imaging After Shoulder Arthroplasty PCAs. CT Shoulder CT plays an important role in the imaging evaluation of a patient with potential loosening that may be missed or incompletely evaluated with radiographs [10,47]. CT provides a better means of evaluating the hardware components and surrounding bone stock [48]. CT can also assess changes in component alignment over time [49].


Imaging After Shoulder Arthroplasty PCAs. Imaging After Shoulder Arthroplasty Image degradation can occur because of beam hardening artifact and other hardware-related artifacts, especially with older CT scanners. The use of newer metal reduction CT software has decreased the artifact-related limitations, improving evaluation [50-52]. Furthermore, dual-energy CT, employing virtual noncalcium software, may provide useful information regarding the presence of marrow edema [53]. CT can also be used to evaluate the bone density around prostheses, which may be predictive of loosening [54].


Imaging After Shoulder Arthroplasty PCAs. Metal reduction protocols and modifications in patient positioning have greatly enhanced the ability of CT to evaluate for complications associated with shoulder arthroplasties. Nevertheless, there are scant studies assessing the benefit of CT in patients with postoperative complications. In a few reports, each including a small group of patients, CT compared with radiographs, has been found to better demonstrate imaging findings such as periprosthetic lucency, osteolysis, hardware malposition, and component migration, as well as the degree of osseous incorporation along the glenoid, deficiency of which has been associated with the risk of failure [10,47,55]. Evaluation of bone graft resorption remains limited on CT because of metal artifact [56]. Dual-energy CT virtual noncalcium techniques, although not yet specifically studied in the postoperative shoulder, may potentially provide useful information about marrow edema associated with the above abnormalities [53]. The addition of intra-articular or IV contrast does not typically improve evaluation [57].


Imaging After Shoulder Arthroplasty PCAs. Fluoride PET/CT Skull Base to Mid-Thigh There is no relevant literature to support the use of fluoride PET/CT after radiographs in a symptomatic patient with a primary shoulder arthroplasty and infection was excluded.


Imaging After Shoulder Arthroplasty PCAs. MRI Shoulder Evolving MRI methods with improved image quality and metal artifact reduction have rendered the modality a more feasible technique for the diagnosis of component loosening, rotator cuff tearing, and, in the presence of hemiarthroplasty, glenoid cartilage wear [37-39,58].


Imaging After Shoulder Arthroplasty PCAs. Because of developments in metal reduction protocols for MRI and research studies showing the benefit of MRI, it can be effective in the evaluation of aseptic loosening [37-39].


Imaging After Shoulder Arthroplasty PCAs. US Shoulder US is limited in the ability to evaluate bone-related complications such as loosening [10].


Imaging After Shoulder Arthroplasty PCAs. Variant 5: Symptomatic patient with a primary shoulder arthroplasty, infection excluded. Suspected rotator cuff tear or other soft-tissue abnormality. Additional imaging following radiographs. The prevalence of rotator cuff tears after arthroplasty placement has been reported to be up to 1.3% [3]. Tears of the subscapularis tendon can present with clinical and radiographic signs of anterior shoulder instability, including varying degrees of anterior subluxation as well as frank dislocation of the humeral head component relative to the glenoid [6,10].


Imaging After Shoulder Arthroplasty PCAs. 3-Phase Bone Scan with SPECT or SPECT/CT Shoulder Nuclear medicine examinations are not typically ordered for the evaluation of rotator cuff tendon abnormalities.


Imaging After Shoulder Arthroplasty PCAs. Bone Scan Shoulder Nuclear medicine examinations are not typically ordered for the evaluation of rotator cuff tendon abnormalities.


Imaging After Shoulder Arthroplasty PCAs. CT Arthrography Shoulder The inherent limited tissue-contrast resolution of CT detracts from its ability to detect rotator cuff tears. A CT arthrogram can be performed when there is suspicion of a rotator cuff tear [10]. CT arthrography can be an effective modality to evaluate the rotator cuff and detect any associated pathology [10,59]. The technique, however, is relatively weak in its ability to assess the extent of partial rotator cuff tears as well in identifying the exact location of the tear when compared with MRI. The presence and degree of fatty muscle replacement can also be used as an indirect sign of a rotator cuff tear [60,61]. Administration of IV contrast does not improve evaluation.


Imaging After Shoulder Arthroplasty PCAs. CT Shoulder The inherent limited tissue-contrast resolution of CT detracts from its ability to detect rotator cuff tears. CT shows promise in assessing the location of the glenoid and humeral components of reverse shoulder prostheses in the setting of soft-tissue impingement [62]. Administration of IV contrast does not improve evaluation.


Imaging After Shoulder Arthroplasty PCAs. Fluoride PET/CT Skull Base to Mid-Thigh Nuclear medicine examinations are not typically ordered for the evaluation of rotator cuff tendon abnormalities.


Imaging After Shoulder Arthroplasty PCAs. Imaging After Shoulder Arthroplasty MRI Shoulder Evolving MRI methods with improved image quality and metal artifact reduction have rendered the modality a more feasible technique for the diagnosis of component loosening, rotator cuff tearing, and, in the presence of hemiarthroplasty, glenoid cartilage wear [37-39,58].


Imaging After Shoulder Arthroplasty PCAs. MRI can be used to evaluate for rotator cuff tendon tearing in the setting of shoulder arthroplasty [38,39]. Advanced metal reduction techniques can reduce the prosthesis-related artifact and thus improve visualization of the rotator cuff tendons and any associated pathology [37,38]. Compared with the other imaging techniques, MRI can also provide a more global evaluation of the arthroplasty components as well as the surrounding soft tissues [37,38]. MRI with metal reduction techniques can also demonstrate failure of subscapularis tendon repair in the setting of arthroplasty, the most common location for rotator cuff pathology in this setting [38].


Imaging After Shoulder Arthroplasty PCAs. There are multiple techniques used to release the subscapularis tendon during arthroplasty placement, including tenotomy, osteotomy, and peel [10]. All of these techniques can predispose to loss of function and tearing of the subscapularis tendon and resultant pain and anterior instability, which can be difficult to diagnose on physical examination [10,63]. This underscores the importance of imaging in this setting. Administration of intra-articular contrast can improve the evaluation for partial-thickness, articular-surface, and full-thickness tears of the rotator cuff, although this is dependent on the degree of prosthesis-related artifact (and any reduction provided by advanced techniques). Administration of IV contrast does not significantly improve evaluation.


Imaging After Shoulder Arthroplasty PCAs. US Shoulder US is a reliable option to evaluate rotator cuff tears in the setting of a shoulder arthroplasty [41]. As opposed to evaluation on MRI, there is no prosthesis-related artifact hindering visualization of the rotator cuff on US. Tears of the supraspinatus, infraspinatus, and subscapularis tendons can all be diagnosed with US as can long-head biceps tendon and subacromial/subdeltoid bursal pathology [41]. US evaluation of the subscapularis tendon has been found to be more reliable than physical examination in the setting of prior tendon repair and arthroplasty placement [63]. Integrity of the subscapularis tendon after reverse shoulder prosthesis placement is also well assessed by US, although the clinical relevance of this integrity is currently unclear [64].


Imaging After Shoulder Arthroplasty PCAs. 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.


Imaging After Shoulder Arthroplasty

Imaging After Shoulder Arthroplasty PCAs. Imaging After Shoulder Arthroplasty


Imaging After Shoulder Arthroplasty PCAs. For additional information on the Appropriateness Criteria methodology and other supporting documents go to www.acr.org/ac.


Imaging After Shoulder Arthroplasty PCAs. Relative Radiation Level Designations 30-100 mSv


10-30 mSv

Imaging After Shoulder Arthroplasty PCAs. 10-30 mSv


Imaging After Shoulder Arthroplasty


Sinonasal Disease

Sinonasal Disease. Introduction/Background According to the American Academy of Otolaryngology-Head and Neck Surgery (AAO-HNS), the term rhinosinusitis refers to symptomatic inflammation of the nasal cavity and paranasal sinuses and is preferred over the term sinusitis, because inflammation of the nasal cavity nearly always accompanies inflammation of the contiguous paranasal sinuses. Rhinosinusitis may be classified as acute rhinosinusitis (ARS) if symptoms last <4 weeks or as chronic rhinosinusitis (CRS) if symptoms last >12 weeks [1]. Patients with acute bacterial rhinosinusitis (ABRS) may develop orbital, intracranial, and vascular complications, including orbital cellulitis, subperiosteal abscess, intracranial abscess, cerebritis, cavernous sinus thrombosis, and aneurysm. Acute recurrent rhinosinusitis refers to when patients have 4 or more episodes of rhinosinusitis per year without persistent symptoms between episodes. CRS is one of the most common chronic illnesses in the United States, affecting approximately 12% to 16% of the population [2], with an overall annual economic burden estimated at $22 billion [3].


Sinonasal Disease

Sinonasal Disease. Acute invasive fungal sinusitis is a fungal infection of the paranasal sinuses with a rapid time course of <4 weeks [4] and a high mortality rate of 50% to 80% [5,6]. Affected patients are typically immunocompromised and include patients with neutropenia, hematologic malignancies, poorly controlled diabetes, acquired immunodeficiency syndrome, organ transplantation, and patients on immunosuppressive therapy including systemic steroids and chemotherapy [4]. Presenting symptoms are nonspecific and include fever, rhinorrhea, and diplopia, similar to those seen with ABRS. Clinicians should maintain a high index of suspicion for this diagnosis in immunocompromised patients with symptoms of ARS, orbital symptoms, and/or headache. [4].


Sinonasal Disease

Sinonasal Disease. Sinonasal neoplasms account for 3% of head and neck neoplasms [7]. Patients with a sinonasal mass may present with nasal congestion, nasal fullness, anosmia, rhinorrhea, and epistaxis [8,9]. Benign lesions include papilloma, respiratory epithelial adenomatoid hamartoma, pleomorphic adenoma, juvenile nasopharyngeal angiofibroma, nerve sheath tumor, and meningioma [7,8]. The most common sinonasal malignancy is squamous cell carcinoma, with other malignancies lymphoma, neuroendocrine tumors, salivary gland tumors, and melanoma [7,10].


Sinonasal Disease

Sinonasal Disease. aNew York University Langone Health, New York, New York. bPanel Chair, University of Iowa Hospitals and Clinics, Iowa City, Iowa. cPanel Vice-Chair, Massachusetts Eye and Ear Infirmary, Harvard Medical School, Boston, Massachusetts. dFroedtert Memorial Lutheran Hospital Medical College of Wisconsin, Milwaukee, Wisconsin. eMontefiore Medical Center, Bronx, New York. fHouston Methodist Hospital, Houston, Texas. gUniversity of Texas Health Science Center, Houston, Texas. hThe University of Texas MD Anderson Cancer Center, Houston, Texas. iMetroHealth Medical Center, Cleveland, Ohio. jEastern Virginia Medical School, Norfolk, Virginia; American Academy of Otolaryngology-Head and Neck Surgery. kUniversity of Texas Health Science Center, Houston, Texas. lMayo Clinic Arizona, Phoenix, Arizona. mUniversity of Iowa Carver College of Medicine, Iowa City, Iowa, Primary care physician. nUniversity of Otago, Dunedin, Otepoti, New Zealand. oGeorge Washington University Hospital, Washington, District of Columbia. pUniversity of Colorado Denver, Denver, Colorado. qSpecialty Chair, Atlanta VA Health Care System and Emory University, Atlanta, Georgia.


Sinonasal Disease

Sinonasal Disease. The American College of Radiology seeks and encourages collaboration with other organizations on the development of the ACR Appropriateness Criteria through representation of such organizations on expert panels. Participation on the expert panel does not necessarily imply endorsement of the final document by individual contributors or their respective organization.


Sinonasal Disease

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


Sinonasal Disease

Sinonasal Disease. Arteriography Craniofacial There is no relevant literature to support the use of arteriography in the evaluation of acute uncomplicated rhinosinusitis.


Sinonasal Disease

Sinonasal Disease. CT Cone Beam Paranasal Sinuses As per clinical practice guidelines from the AAO-HNS, CT imaging of the sinuses is unnecessary for patients with a clinical diagnosis of ARS [1]. CT has not been shown to accurately distinguish ABRS from ARS of viral etiology [1,17,18]. Moreover, cone beam CT (CBCT) is limited in the evaluation of the soft tissues and is therefore not helpful in the imaging assessment of complications of sinus disease [19].


Sinonasal Disease

Sinonasal Disease. CT Head As per clinical practice guidelines from the AAO-HNS, imaging is unnecessary for patients with a clinical diagnosis of ARS [1]. There is no relevant literature to support the use of CT head in the evaluation of acute uncomplicated rhinosinusitis.


Sinonasal Disease

Sinonasal Disease. CT Maxillofacial As per clinical practice guidelines from the AAO-HNS, CT imaging of the sinuses is unnecessary for patients with a clinical diagnosis of ARS [1]. CT has not been shown to accurately distinguish ABRS from ARS of viral etiology [1,17,18].


Sinonasal Disease

Sinonasal Disease. CTA Head There is no relevant literature to support the use of CT angiography (CTA) head in the evaluation of acute uncomplicated rhinosinusitis.


Sinonasal Disease

Sinonasal Disease. FDG-PET/CT Skull Base to Mid-Thigh There is no relevant literature to support the use of fluorine-18-2-fluoro-2-deoxy-D-glucose (FDG)-PET/CT in the evaluation of acute uncomplicated rhinosinusitis.


Sinonasal Disease

Sinonasal Disease. MRA Head There is no relevant literature to support the use of MR angiography (MRA) head in the evaluation of acute uncomplicated rhinosinusitis.


Sinonasal Disease

Sinonasal Disease

Sinonasal Disease. Sinonasal Disease


Sinonasal Disease

Sinonasal Disease. MRI Head As per clinical practice guidelines from the AAO-HNS, imaging is unnecessary for patients with a clinical diagnosis of ARS [1]. There is no relevant literature to support the use of MRI head in the evaluation of acute uncomplicated rhinosinusitis.


Sinonasal Disease

Sinonasal Disease. MRI Orbits, Face, and Neck As per clinical practice guidelines from the AAO-HNS, imaging is unnecessary for patients with a clinical diagnosis of ARS [1]. There is no relevant literature to support the use of MRI of the orbits, face, and neck in the evaluation of acute uncomplicated rhinosinusitis.


Sinonasal Disease

Sinonasal Disease. Radiography Paranasal Sinuses As per clinical practice guidelines from the AAO-HNS, imaging of the sinuses is unnecessary for patients with a clinical diagnosis of ARS [1]. Radiography lacks specificity for the identification of ABRS, because sinus fluid can also be seen with viral upper respiratory tract infections [20]. Compared with CT, radiography has been shown to have a low sensitivity of 25% to 41% for all sinus groups except the maxillary sinuses with 80% sensitivity [21]. In a meta-analysis of 6 studies, radiographs of the paranasal sinuses demonstrated a sensitivity of 76% and specificity of 79% for the diagnosis of ABRS compared with sinus puncture [22].


Sinonasal Disease

Sinonasal Disease. SPECT or SPECT/CT Paranasal Sinuses There is no relevant literature to support the use of single-photon emission CT (SPECT) or SPECT/CT in the evaluation of acute uncomplicated rhinosinusitis.


Sinonasal Disease

Sinonasal Disease. Variant 2: Acute rhinosinusitis with suspected orbital or intracranial complication. Initial imaging. ABRS may spread to the orbital and intracranial compartments through neurovascular foramina, areas of osseous erosion, or hematogenous spread along valveless veins [6]. Orbital complications are more common and include orbital cellulitis, subperiosteal abscess, and orbital abscess. Symptoms suggesting orbital involvement include eye swelling with or without proptosis, impaired eye movement, and decreased visual acuity [17,23]. Intracranial complications most commonly occur with frontal sinusitis and include epidural abscess, subdural empyema, cerebritis, brain abscess, and meningitis. Symptoms suggesting intracranial involvement include severe headache, photophobia, seizures, or other focal neurologic findings [6,17]. Vascular complications include cavernous sinus thrombosis and rarely pseudoaneurysm formation [2,24].


Sinonasal Disease

Sinonasal Disease. Arteriography Craniofacial Arteriography may be performed for the evaluation of a pseudoaneurysm, although this would not be performed in the initial imaging evaluation. There is no relevant literature to support the use of arteriography in the evaluation of ARS with suspected orbital or intracranial complication.


Sinonasal Disease

Sinonasal Disease. CT Cone Beam Paranasal Sinuses CBCT is not helpful in the imaging assessment of patients with ARS with suspected orbital or intracranial complications because of a limited evaluation of the soft-tissue structures [19,25].


Sinonasal Disease

Sinonasal Disease. CT Head CT maxillofacial is useful as the first-line CT examination for patients with ARS with suspected intraorbital and intracranial complications, because complications adjacent to the paranasal sinuses are typically included in the field of view. MRI is overall more useful than CT for the evaluation of intracranial complications, but because CT may be the first imaging study ordered, contrast-enhanced CT head may be added to the CT maxillofacial examination for increased coverage of a suspected intracranial complication. CT head with intravenous (IV) contrast can accurately identify clinically suspected intracranial complications including epidural abscess, subdural empyema, cerebritis, and brain abscess. The accuracy for the detection of intracranial complications has been reported to be 87% for CT, compared with 97% for MRI [23], although the detection of cavernous sinus thrombosis, meningitis, and early cerebritis is more difficult on CT compared with MRI [6,17,23]. There is no relevant literature to support the use of noncontrast CT head or combined pre- and postcontrast CT imaging.


Sinonasal Disease

Sinonasal Disease. CT Maxillofacial CT of the paranasal sinuses with IV contrast can accurately confirm paranasal sinus inflammation and identify orbital complications and adjacent intracranial complications included in the field of view [17]. Given its detailed depiction of bony anatomy, CT can also accurately demonstrate the presence of erosions of the sinus and orbital walls. Studies have demonstrated a higher accuracy of CT compared with clinical examination for detecting orbital complications, with an accuracy of 87% to 91% [23]. CT also enables surgical planning given its detailed depiction


Sinonasal Disease

Sinonasal Disease. of sinonasal anatomy and can be used for surgical image-guidance systems. Although MRI is overall more useful than CT for the evaluation of intracranial and intraorbital complications, CT is often the first imaging study ordered. A noncontrast CT may be performed for bony evaluation and surgical planning but is limited in the detection of orbital and intracranial complications. There is no relevant literature to support the use of combined pre- and postcontrast CT imaging.


Sinonasal Disease

Sinonasal Disease. CTA Head CTA head may be performed for the evaluation of a pseudoaneurysm, but this is typically not performed in the initial imaging evaluation. There is no relevant literature to support the use of CTA head in the evaluation of ARS with suspected orbital or intracranial complication.


Sinonasal Disease

Sinonasal Disease. FDG-PET/CT Skull Base to Mid-Thigh There is no relevant literature to support the use of FDG-PET/CT in the evaluation of ARS with suspected orbital or intracranial complication.


Sinonasal Disease

Sinonasal Disease. MRA Head MRA head may be performed for the evaluation of a pseudoaneurysm, but this is typically not performed in the initial imaging evaluation. There is no relevant literature to support the use of MRA head in the evaluation of ARS with suspected orbital or intracranial complication.


Sinonasal Disease

Sinonasal Disease. MRI Head MRI head without and with IV contrast can accurately identify clinically suspected intracranial complications including cavernous sinus thrombosis, epidural abscess, subdural empyema, cerebritis, brain abscess, and meningitis, with a reported 97% diagnostic accuracy compared with 87% for CT and a superior accuracy in particular for the diagnosis of meningitis [17,23]. Combined pre- and postcontrast imaging provides the best opportunity to identify and characterize potential intracranial complications. Restricted diffusion on diffusion- weighted sequences can accurately identify the presence of purulent material within extra-axial collections and brain abscesses.


Sinonasal Disease

Sinonasal Disease. MRI Orbits, Face, and Neck MRI orbits, face, and neck without and with IV contrast can confirm paranasal sinus inflammation and identify orbital complications and adjacent intracranial complications included in the field of view [17]. This study may be done in conjunction with MRI head for suspected orbital and intracranial complications. Although noncontrast imaging can demonstrate fluid collections and edema, combined pre- and postcontrast imaging provides the best opportunity to identify and characterize potential orbital and intracranial complications.


Sinonasal Disease

Sinonasal Disease. Radiography Paranasal Sinuses There is no relevant literature to support the use of radiography in the evaluation of ARS with suspected orbital or intracranial complication. Radiography is limited in the evaluation of soft-tissue structures.


Sinonasal Disease

Sinonasal Disease. SPECT or SPECT/CT Paranasal Sinuses There is no relevant literature to support the use of SPECT or SPECT/CT in the evaluation of ARS with suspected orbital or intracranial complication.


Sinonasal Disease

Sinonasal Disease. Variant 3: Acute recurrent sinusitis or chronic rhinosinusitis or noninvasive fungal sinusitis or sinonasal polyposis. Possible surgical candidate for these indications or other non-neoplastic indications, including suspected silent sinus syndrome or suspected mucocele, or deviated nasal septum. Initial imaging. CRS refers to rhinosinusitis lasting >12 weeks, and the most common symptoms of CRS include nasal obstruction, facial congestion and pressure, discolored nasal discharge, and hyposmia [26]. The presence of 2 or more of these symptoms for >12 weeks is highly sensitive for the diagnosis of CRS, but because these symptoms are nonspecific, documentation of inflammation on endoscopy or imaging is required to confirm the diagnosis [26]. Imaging findings that confirm CRS include mucosal thickening, sinus opacification, polyps or retention cysts, and sclerosis and thickening of the sinus walls [2,26].


Sinonasal Disease

Sinonasal Disease. Studies have shown variable correlation between the imaging findings and clinical symptoms of CRS. The Lund- Mackay and modified Lund-Mackay system are the most commonly used imaging staging systems, with some studies showing good correlation with disease severity and surgical outcomes [2,27,28]. Some studies have not demonstrated a correlation between symptom severity and CT findings [29-31], although correlation may be higher in patients with associated nasal polyps [29].


Sinonasal Disease

Sinonasal Disease

Sinonasal Disease. Sinonasal Disease


Sinonasal Disease

Sinonasal Disease. Functional endoscopic sinus surgery is now the standard of care for restoring patency of paranasal sinus outflow tracts, with postoperative improvement in symptoms and quality of life reported in over 75% of patients [32]. Functional endoscopic sinus surgery may be performed for CRS and other nonneoplastic indications including acute recurrent rhinosinusitis, noninvasive fungal sinusitis and fungus ball, sinonasal polyposis, silent sinus syndrome, mucocele, and deviated nasal septum. Imaging that provides anatomical detail is needed for surgical planning, in particular for the identification of anatomic variants and abnormalities that can increase the risk for intracranial, intraorbital, and vascular injury.


Sinonasal Disease

Sinonasal Disease. Arteriography Craniofacial There is no relevant literature to support the use of arteriography in the evaluation of CRS or for presurgical planning of paranasal sinus inflammatory disease.


Sinonasal Disease

Sinonasal Disease. CT Cone Beam Paranasal Sinuses CBCT has been shown to have high accuracy for evaluating odontogenic and nonodontogenic sinusitis, with strong agreement between CBCT and sinus endoscopy [33]. Similar to standard multidetector CT, CBCT can confirm the diagnosis of CRS and identify anatomic variants for presurgical planning. One study showed decreased detection of intrasinus calcifications in patients with noninvasive fungal sinusitis compared with multidetector CT, although comparison between the 2 modalities was done in separate patient cohorts [34]. CBCT is limited in the evaluation of soft-tissue structures and therefore is not the imaging modality of choice if extrasinus disease is suspected [19,25].


Sinonasal Disease

Sinonasal Disease. CT Head Given its typical incomplete coverage of the paranasal sinuses, CT head is not typically performed for the evaluation of CRS or for presurgical planning of paranasal sinus inflammatory disease.


Sinonasal Disease

Sinonasal Disease. CT Maxillofacial Given its excellent bony detail, multidetector CT without IV contrast is useful for confirming and evaluating CRS and for presurgical planning. Imaging findings that confirm CRS include mucosal thickening, sinus opacification, polyps or retention cysts, and sclerosis and thickening of the sinus walls [2,26]. CT has been shown to accurately identify these findings of CRS, although the findings have been shown to not necessarily correlate with the severity of symptoms [26]. CT can also evaluate the extent of disease and identify anatomic variants that narrow sinus drainage pathways [32].


Sinonasal Disease

Sinonasal Disease. CT is critical for surgical planning, in particular for the identification of anatomic variants and abnormalities that can increase the risk for intracranial, intraorbital, and vascular injury as well as for CSF leak [31,32]. Low-dose techniques have been shown to be limited in the visualization of surgically relevant anatomical structures including the cribriform plates, lamina papyracea, and anterior ethmoidal artery canal in the setting of CRS with nasal polyps and a history of sinus surgery [35]. A sinus CT protocol that can be utilized by image guidance systems is recommended [36].


Sinonasal Disease

Sinonasal Disease. Contrast-enhanced CT is not necessary to demonstrate findings of CRS or for surgical planning of paranasal sinus inflammatory disease. There is no relevant literature to support the use of combined pre- and postcontrast CT imaging.


Sinonasal Disease

Sinonasal Disease. Silent sinus syndrome is atelectasis of the maxillary sinus due to intrasinus negative pressure from chronic ostial obstruction. Both CT and MRI can demonstrate decreased maxillary sinus volume and inward bowing of the sinus walls characteristic of silent sinus syndrome, but additional findings of osseous thinning, obstruction of the infundibulum, and lateralization of the uncinate process are better delineated on CT compared with MRI [37].


Sinonasal Disease

Sinonasal Disease. Nasal septal deviation can cause symptomatic nasal obstruction and can also be a risk factor for CRS. Clinical anterior rhinoscopy and endoscopic examination is the reference standard for evaluating nasal septal deviation. CT has been shown to have limited correlation with physical examination, and CT may underestimate the degree of nasal obstruction due to septal deviation at the internal nasal valve. CT therefore should not be performed solely for the evaluation of septal deviation but rather for the evaluation of any associated symptoms of CRS [38].


Sinonasal Disease

Sinonasal Disease. CTA Head There is no relevant literature to support the use of CTA head in the evaluation of CRS or for presurgical planning of paranasal sinus inflammatory disease.


Sinonasal Disease

Sinonasal Disease. FDG-PET/CT Skull Base to Mid-Thigh There is no relevant literature to support the use of FDG-PET/CT in the evaluation of CRS or for presurgical planning of paranasal sinus inflammatory disease.


Sinonasal Disease

Sinonasal Disease. MRA Head There is no relevant literature to support the use of MRA head in the evaluation of CRS or for presurgical planning of paranasal sinus inflammatory disease.


Sinonasal Disease

Sinonasal Disease. MRI Head There is no relevant literature to support the use of MRI head in the evaluation of CRS or for presurgical planning of paranasal sinus inflammatory disease.


Sinonasal Disease

Sinonasal Disease. MRI Orbits, Face, and Neck MRI is not useful as the first-line study for routine sinus imaging because of the lack of bony detail. In addition, inspissated secretions may demonstrate a signal void that mimics air on T2-weighted sequences [39]. However, one study examined 89 adult patients imaged with both CT and MRI within a 3-month period for evaluation of pituitary disease and showed significant correlation between CT and MRI based Lund-Mackay staging scores of sinus disease; T1- and T2-weighted sequences were utilized for MRI scoring [40]. The utilization of IV contrast was not specified, and the Lund-Mackay scores were not correlated with patient symptoms in this study. In select cases, evaluation with MRI without and with IV contrast may be helpful to differentiate fluid secretions from inflamed mucosa and exclude an underlying obstructing mass [24].


Sinonasal Disease

Sinonasal Disease. Radiography Paranasal Sinuses Detection of mucosal thickening is limited on radiography because of overlapping osseous structures [41]. CT has largely replaced radiography given its superior depiction of sinonasal anatomy and pathology and the need for greater anatomic detail for functional endoscopic sinus surgery planning [2,41].


Sinonasal Disease

Sinonasal Disease. SPECT or SPECT/CT Paranasal Sinuses In a pilot study of 24 patients with CRS, a positive SPECT correlated with more extensive disease on CT and poor subjective response to medical treatment [42]. However, the use of SPECT remains limited in the evaluation of CRS, and this technique is generally not used in clinical practice.


Sinonasal Disease

Sinonasal Disease. Variant 4: Acute sinusitis with rapid progression or suspected invasive fungal sinusitis. Initial imaging. Acute invasive fungal sinusitis is a fungal infection of the paranasal sinuses with a rapid time course of <4 weeks [4] and a high mortality rate of 50% to 80% [5,6]. Affected patients are typically immunocompromised and include patients with neutropenia, hematologic malignancies, poorly controlled diabetes, acquired immunodeficiency syndrome, and organ transplantation and patients on immunosuppressive therapy including systemic steroids and chemotherapy [4,5]. Aspergillus and Mucoraceae species are seen in most cases. Presenting symptoms are nonspecific and include fever, rhinorrhea, and diplopia, similar to those seen with ABRS. Clinicians should maintain a high index of suspicion for this diagnosis in immunocompromised patients with symptoms of ARS, orbital symptoms, and/or headache. Nasal endoscopy may demonstrate pale mucosa progressing to ulceration and necrosis [4]. Definitive diagnosis is made on biopsy with the identification of invasive fungi in the sinonasal mucosa, vessels, and bone [4]. Given the angioinvasive nature of the fungi, complications include thrombosis, dissection, and pseudoaneurysm formation of the intracranial arteries, thrombosis of the cavernous sinus, infarction, and hemorrhage [4,6]. Treatment typically includes both systemic antifungal medication and surgical debridement.


Sinonasal Disease

Sinonasal Disease. Arteriography Craniofacial Arteriography may be performed for further characterization and confirmation of vascular complications of invasive fungal sinusitis detected by MRI, MRA, or CTA, including pseudoaneurysm formation, thrombosis, and dissection, although this would not be performed in the initial imaging evaluation. There is no relevant literature to support the use of arteriography in the initial evaluation of suspected acute invasive fungal sinusitis.


Sinonasal Disease

Sinonasal Disease. CT Cone Beam Paranasal Sinuses CBCT is not helpful in the imaging assessment of patients with ARS with suspected orbital or intracranial complications because of the limited evaluation of the soft-tissue structures [19,25].


Sinonasal Disease

Sinonasal Disease

Sinonasal Disease. Sinonasal Disease


Sinonasal Disease

Sinonasal Disease. CT Head CT head with IV contrast may be used to demonstrate intracranial complications but is less sensitive compared with MRI [6,23,43]. There is no relevant literature to support the use of noncontrast CT head or combined pre- and postcontrast CT imaging.


Sinonasal Disease

Sinonasal Disease. CT Maxillofacial Noncontrast CT is effective in the evaluation of fungal sinusitis because it can demonstrate hyperattenuation in the involved sinus, bony erosions, and infiltration of the surrounding spaces [4,44]. Hyperattenuation within the paranasal sinuses can suggest the diagnosis but is nonspecific. Features including bone erosion and infiltration of the periantral fat have a high specificity but a limited sensitivity, particularly in the early phase of the disease, and severe predominantly unilateral nasal cavity mucosal thickening has a high sensitivity but low specificity [5,6,44]. In a retrospective study evaluating 42 patients with pathology-proven acute invasive fungal rhinosinusitis and 42 control patients from the same high-risk population, a 7-variable model was synthesized using infiltration of the periantral fat, pterygopalatine fossa, nasolacrimal duct and lacrimal sac, bone dehiscence, septal ulceration, and orbital involvement; positive findings in any 2 of the model variables demonstrated 88% sensitivity and 100% specificity [44]. Emphysematous soft tissue in the nasal cavity is also a specific sign of early invasive fungal sinusitis [5].


Sinonasal Disease

Sinonasal Disease. CT also enables surgical planning given its detailed depiction of sinonasal anatomy and can be used with surgical image-guidance systems when acquired with the appropriate protocol.


Sinonasal Disease

Sinonasal Disease. CT with IV contrast may also be used to help demonstrate orbital and intracranial complications included in the field of view. [6,23,43]. There is no relevant literature to support the use of combined pre- and postcontrast CT imaging.


Sinonasal Disease

Sinonasal Disease. CTA Head CTA head may be performed for the evaluation of vascular complications of invasive fungal sinusitis including pseudoaneurysm formation, thrombosis, and dissection, although this would not be performed in the initial imaging evaluation. There is no relevant literature to support the use of CTA head in the initial evaluation of suspected acute invasive fungal sinusitis.


Sinonasal Disease

Sinonasal Disease. FDG-PET/CT Skull Base to Mid-Thigh There is no relevant literature to support the use of FDG-PET/CT in the evaluation of acute invasive fungal sinusitis.


Sinonasal Disease

Sinonasal Disease. MRA Head MRA head may be performed for the evaluation of vascular complications of invasive fungal sinusitis including pseudoaneurysm formation, thrombosis, and dissection, although this would not be performed in the initial imaging evaluation. There is no relevant literature to support the use of MRA head in the initial evaluation of suspected invasive fungal sinusitis.


Sinonasal Disease

Sinonasal Disease. MRI Head MRI head without and with IV contrast can delineate complications involving the intracranial compartment better than CT [5,6,43]. Combined pre- and postcontrast imaging provides the best opportunity to identify and characterize potential intracranial complications. MRI head with and without IV contrast may be complementary to CT maxillofacial to identify intracranial spread beyond the field of view of the MRI orbits, face, and neck examination.


Sinonasal Disease

Sinonasal Disease. MRI Orbits, Face, and Neck A T2 signal void from fungal concretions can be confused for a pneumatized sinus, limiting evaluation of intrasinus disease with MRI [4,5]. However, MRI without and with IV contrast provides accurate evaluation of the invasion of the surrounding soft tissues, orbits, and intracranial compartment and vascular complications. One study evaluating 17 immunocompromised patients with acute invasive fungal sinusitis and 6 controls found increased sensitivity of MRI of 85% to 86% compared with CT with a sensitivity of 57% to 69% and found extrasinus invasion to be the most sensitive imaging finding [4,45]. Lack of sinonasal mucosal and nasal turbinate enhancement, the latter described as the black turbinate sign, correlates with necrosis related to the angioinvasive nature of fungal sinusitis [4]. In a study from Korea evaluating 23 patients with acute invasive fungal rhinosinusitis, extrasinonasal extension was demonstrated in all cases on MRI, with orbital extension in 65%; lack of contrast enhancement was seen in 48% of patients and was found to be a prognostic factor for disease-specific mortality [46]. Although noncontrast imaging can demonstrate fluid collections and edema, combined pre- and postcontrast imaging provides the best opportunity to identify and characterize potential orbital, intracranial, and vascular complications.


Sinonasal Disease

Sinonasal Disease. Radiography Paranasal Sinuses Radiography of the paranasal sinuses is considered to be of limited usefulness given a large number of false-negative results [47]. Findings of bone erosion may be seen in advanced cases, but CT is more useful for the detection of bony erosion and adjacent soft-tissue involvement.


Sinonasal Disease

Sinonasal Disease. SPECT or SPECT/CT Paranasal Sinuses There is no relevant literature to support the use of SPECT or SPECT/CT in the evaluation of acute invasive fungal sinusitis.


Sinonasal Disease

Sinonasal Disease. Variant 5: Suspected sinonasal mass. Initial imaging. Patients with a sinonasal mass may present with nasal congestion, nasal fullness, anosmia, rhinorrhea, and epistaxis [8,9]. Benign lesions include papilloma, respiratory epithelial adenomatoid hamartoma, pleomorphic adenoma, juvenile nasopharyngeal angiofibroma, nerve sheath tumor, and meningioma [7,8]. The most common sinonasal malignancy is squamous cell carcinoma, with other malignancies including sinonasal undifferentiated carcinoma, adenocarcinoma, lymphoma, neuroendocrine tumors, salivary gland tumors, and melanoma [7,10]. A meningoencephalocele may also present as a sinonasal mass.


Sinonasal Disease

Sinonasal Disease. Imaging may demonstrate specific features of a sinonasal mass, which can narrow a differential diagnosis and occasionally facilitate a specific diagnosis. Ultimately, very few imaging features are pathognomonic and most sinonasal neoplasms require histologic sampling for a specific diagnosis [7,24]. The main role of imaging in these cases is to delineate the extent of disease for treatment planning.


Sinonasal Disease

Sinonasal Disease. Arteriography Craniofacial Catheter angiography is typically not useful in the initial imaging evaluation of a sinonasal mass. It may be useful for preoperative planning, preoperative embolization of a vascular mass, or to treat severe epistaxis [43,48-50].


Sinonasal Disease

Sinonasal Disease. CT Cone Beam Paranasal Sinuses CBCT is not useful in the workup of patients with sinonasal mass because of the limitations in assessing soft-tissue structures.


Sinonasal Disease

Sinonasal Disease. CT Head CT best depicts osseous changes, although it is limited in determining soft-tissue and intracranial extent. Although MRI is useful for evaluating intracranial extension of a sinonasal mass, contrast-enhanced CT can also be useful for evaluating the soft-tissue and intracranial extent of the mass [51]. CT maxillofacial is useful as the first-line CT examination for suspected sinonasal mass, but contrast-enhanced CT head may be added if increased coverage of the intracranial component of a mass and its associated mass effect of the intracranial structures is required. There is no relevant literature to support the use of noncontrast CT head or combined pre- and postcontrast CT imaging.


Sinonasal Disease

Sinonasal Disease. CT Maxillofacial CT best depicts osseous changes and can help distinguish bony remodeling that is more typical of slow growing or benign masses from lytic destruction seen with more aggressive malignancies [7,51]. CT can demonstrate lesion mineralization, including the osseous matrix of osteomas, the chondroid matrix of cartilaginous tumors, and the ground glass density of fibro-osseous lesions. CT also best depicts invasion of the surrounding osseous structures, although it is limited in determining soft-tissue and intracranial extent and in distinguishing tumor from sinonasal inflammation.


Sinonasal Disease

Sinonasal Disease. CT and MRI are complementary imaging modalities in the evaluation of sinonasal masses, localizing and characterizing lesions and determining their extent for treatment planning. If an MRI is also planned or performed, the CT can be performed without IV contrast because the main purpose of the CT is to evaluate osseous involvement. Although MRI is superior for evaluating the soft tissues, contrast-enhanced CT can also be useful for evaluating the soft-tissue and intracranial extent of the mass [51].


Sinonasal Disease

Sinonasal Disease. CT maxillofacial also enables surgical planning given its detailed depiction of sinonasal anatomy and can be used with surgical image-guidance systems when acquired with the appropriate protocol.


Sinonasal Disease

Sinonasal Disease. CTA Head CTA head is typically not useful in the initial imaging evaluation of a sinonasal mass. It may be useful for preoperative planning of a vascular mass [43,48-50].


Sinonasal Disease

Sinonasal Disease

Sinonasal Disease. Sinonasal Disease


Sinonasal Disease

Sinonasal Disease. FDG-PET/CT Skull Base to Mid-Thigh FDG-PET/CT is not useful for the initial evaluation of a sinonasal mass but can be used to detect regional and distant metastases in the staging workup of malignant neoplasms [7].


Sinonasal Disease

Sinonasal Disease. MRA Head MRA head typically is not useful in the initial imaging evaluation of a sinonasal mass. It may be useful for preoperative planning of a vascular mass [43,48-50].


Sinonasal Disease

Sinonasal Disease. MRI Head MRI head may be performed in addition to the MRI maxillofacial examination if increased coverage of the intracranial component of a mass and its associated mass effect of the intracranial structures is required. Combined pre- and postcontrast imaging provides the best opportunity to identify intracranial extension and to characterize potential intracranial complications.


Sinonasal Disease

Sinonasal Disease. MRI Orbits, Face, and Neck MRI without and with IV contrast can best characterize the soft-tissue components of a mass and can occasionally demonstrate signal characteristics suggestive of specific pathology. For example, MRI can demonstrate the convoluted cerebriform pattern of inverted papillomas on T2-weighted and contrast-enhanced T1-weighted MRI; the intrinsic T1 hyperintensity of melanotic melanomas; and peritumoral intracranial cysts, which are suggestive of, but not specific for, esthesioneuroblastoma [7,8]. Decreased T2 signal and apparent diffusion coefficient correlate with increased cellularity of tumors [9]. Perfusion MRI can also potentially provide diagnostic information of sinonasal masses [52,53].


Sinonasal Disease

Sinonasal Disease. For tumor mapping, MRI is more helpful than CT for soft tissue contrast and can better distinguish tumors from the more T2 hyperintense sinus inflammatory changes and retained secretions. MRI can also best identify intracranial and perineural involvement important for staging and presurgical planning [7,24]. Compared with CT, MRI can also better detect osseous marrow invasion.


Sinonasal Disease

Sinonasal Disease. CT and MRI are complementary imaging modalities in the evaluation of sinonasal masses, localizing and characterizing lesions, and determining their extent for treatment planning.


Sinonasal Disease

Sinonasal Disease. Radiography Paranasal Sinuses Radiography is not considered to be part of the imaging workup of sinonasal neoplasms [51].


Sinonasal Disease

Sinonasal Disease. SPECT or SPECT/CT Paranasal Sinuses There is no relevant literature to support the use of SPECT or SPECT/CT in the evaluation of a sinonasal mass.


Sinonasal Disease

Sinonasal Disease. Arteriography Craniofacial There is no relevant literature to support the use of arteriography in the evaluation of sinonasal CSF leak.


Sinonasal Disease

Sinonasal Disease. CT Cone Beam Paranasal Sinuses There is no relevant literature regarding the use of CBCT paranasal sinuses in the evaluation of sinonasal CSF leak.


Sinonasal Disease

Sinonasal Disease. CT Head Cisternography CT head cisternography is performed by spinal injection of intrathecal contrast, with images performed before and after contrast administration. Interval contrast pooling adjacent to an osseous defect can be identified with demonstration of a 50% or greater increase in Hounsfield units between the pre- and postcontrast scans [12]. CT head cisternography is primarily used in the setting of multiple osseous defects on high-resolution CT (HRCT) to


Sinonasal Disease

Sinonasal Disease. determine the specific site of the leak [12]. CT cisternography has a reported sensitivity of 33% to 100% and a specificity of 94% [12,13,55-58]. The primary limitation of CT cisternography is that the patient needs to have an active CSF leak at the time of this examination for the study to be potentially diagnostic. Studies comparing CT cisternography with MRI have demonstrated CT cisternography to have a lower sensitivity of 33% to 72% versus 67% to 93% for MRI with a heavily T2-weighted sequence (MR cisternogram) and 80% for contrast-enhanced MR cisternogram [13,59,60].


Sinonasal Disease

Sinonasal Disease. CT Head Given its typical incomplete coverage of the paranasal sinuses, CT head is not typically performed for the evaluation of sinonasal CSF leak.


Sinonasal Disease

Sinonasal Disease. HRCT also enables surgical planning given its detailed depiction of sinonasal anatomy and can be used with surgical image-guidance systems when acquired with the appropriate protocol. HRCT can identify the skull base defect even in the absence of an active leak; however, it is limited in identifying a specific site of the leak if the patient has multiple osseous defects because it is not clear which defect is the source of the leak [12]. A combination of HRCT and MRI with a heavily T2-weighted sequence has a reported sensitivity of 90% to 96% [13,55,61]. HRCT alone is sufficient if only 1 osseous defect is identified and corresponds with the clinical symptoms [12]. HRCT may also be the only study required in patients with iatrogenic CSF leaks for preoperative planning, because the surgical site of leak is known [12].


Sinonasal Disease

Sinonasal Disease. There is no relevant literature to support the use of contrast-enhanced CT or combined pre- and postcontrast CT in the evaluation of CSF leak.


Sinonasal Disease

Sinonasal Disease. CTA Head There is no relevant literature to support the use of CTA head in the evaluation of sinonasal CSF leak.


Sinonasal Disease

Sinonasal Disease. FDG-PET/CT Skull Base to Mid-Thigh There is no relevant literature to support the use of FDG-PET/CT in the evaluation of sinonasal CSF leak.


Sinonasal Disease

Sinonasal Disease. MRA Head There is no relevant literature to support the use of MRA head in the evaluation of sinonasal CSF leak.


Sinonasal Disease

Sinonasal Disease. MRI Head MRI with the inclusion of heavily T2-weighted images is often referred to as an MR cisternogram and is considered the second choice of study and should be done only in conjunction with HRCT [12,55,61]. The heavily T2-weighted sequence covering the roof of the sinonasal cavity in the coronal plane can be included in either an MRI head examination or an MRI orbits, face, and neck examination. A 3-D isotropic heavily T2-weighted sequence should be obtained to provide submillimeter high spatial and contrast resolution and allow for reformats in multiple planes. The site of the CSF leak can be demonstrated on MRI with identification of CSF extending from the subarachnoid space into the sinonasal space through an osseous defect seen on a concurrent or prior CT examination, with or without an associated cephalocele. Sensitivity of 56% to 94% and specificity of 57% to 100% have been reported


Sinonasal Disease

Sinonasal Disease

Sinonasal Disease. Sinonasal Disease


Sinonasal Disease

Sinonasal Disease. for the identification of the site of the CSF leak [12-14,55,58,61,63]. Given its superior soft-tissue contrast, MRI can also identify the contents of a cephalocele if present.


Sinonasal Disease

Sinonasal Disease. MRI without IV contrast with inclusion of heavily T2-weighted images is typically sufficient for the evaluation of CSF leak. However, MRI without and with IV contrast may be useful for identifying dural enhancement and distinguishing a meningoceles from sinus secretions [11].


Sinonasal Disease

Sinonasal Disease. MRI Orbits, Face, and Neck MRI with the inclusion of heavily T2-weighted images is often referred to as an MR cisternogram and may be considered the second choice of study and should be done only in conjunction with HRCT [12,55,61]. The heavily T2-weighted sequence covering the roof of the sinonasal cavity in the coronal plane can be included in either an MRI head examination or an MRI orbits, face, and neck examination. A 3-D isotropic heavily T2-weighted sequence should be obtained to provide submillimeter high spatial and contrast resolution and to allow for reformats in multiple planes. The site of the CSF leak can be demonstrated on MRI with identification of CSF extending from the subarachnoid space into the sinonasal space with or without an associated cephalocele. Sensitivity of 56% to 94% and specificity of 57% to 100% have been reported for the identification of the site of the CSF leak [12- 14,55,58,61,63]. Given its superior soft-tissue contrast, MRI can also identify the contents of a cephalocele if present.


Sinonasal Disease

Sinonasal Disease. MRI without IV contrast with inclusion of heavily T2-weighted images is typically sufficient for the evaluation of a CSF leak. However, MRI without and with IV contrast may be useful for identifying dural enhancement and distinguishing a meningoceles from sinus secretions [11].


Sinonasal Disease

Sinonasal Disease. Contrast-enhanced MR cisternogram is performed by spinal injection of intrathecal gadolinium, with thin-section T1-weighted images obtained before and after contrast injection. The postinjection images can be obtained immediately after contrast administration or at delayed intervals up to 24 hours after contrast administration. This technique allows for detection of both high-flow and slow-flow leaks and allows for simultaneous evaluation of cephaloceles that may be present. Sensitivity up to 100% has been reported for high-flow leaks and 60% to 70% for slow-flow leaks [12,65]. Studies have demonstrated contrast-enhanced MR cisternogram to have a higher sensitivity of 80% when compared with 33% to 72% of CT cisternogram [13,60]. Intrathecal administration of gadolinium contrast is not currently approved by the US Food and Drug Administration and requires off-label use consent [12].


Sinonasal Disease

Sinonasal Disease. Radiography Paranasal Sinuses There is no relevant literature to support the use of radiography in the evaluation of a sinonasal CSF leak.


Sinonasal Disease

Sinonasal Disease. SPECT or SPECT/CT Paranasal Sinuses Three studies evaluating the efficacy of SPECT cisternography after the intrathecal injection of radiotracer reported a sensitivity of 94% with SPECT planar imaging and 94% to 100% for SPECT/CT fusion imaging for localization [13,66]. This study is not typically useful in the initial imaging evaluation of a CSF leak. It may be performed if the HRCT fails to show a defect or if CT shows multiple defects and for slow-flow leaks if the CT cisternogram fails to identify the source of leak.


Sinonasal Disease

Sinonasal 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.


Sinonasal Disease

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


Staging of Colorectal Cancer

Staging of Colorectal Cancer. In patients with locally advanced rectal cancer (LARC), established risk factors for poorer outcomes include circumferential resection margin involvement, extramural depth of spread >5 mm, extramural vascular invasion (EMVI), mucinous phenotype, and poor response to chemoradiotherapy (CRT) [9,10]. Multiple studies have demonstrated relatively poor compliance with adjuvant (postoperative) chemotherapy compared with neoadjuvant treatment, with decreased survival in the adjuvant (versus neoadjuvant) cohort [11]. Prospective studies have demonstrated that preoperative or neoadjuvant radiation with or without sensitizing chemotherapy reduced local recurrence risk and may increase the proportion of patients who benefit from a sphincter-saving procedure.


Staging of Colorectal Cancer

Staging of Colorectal Cancer. There is an ongoing effort to assess for complete response to neoadjuvant therapy in an effort to determine which patients could potentially benefit from an organ-preservation approach without total mesorectal excision or lateral nodal dissection.


Staging of Colorectal Cancer

Staging of Colorectal Cancer. aOregon Health and Science University, Portland, Oregon. bEmory University, Atlanta, Georgia. cPanel Chair, University of Wisconsin Hospital & Clinics, Madison, Wisconsin. dPanel Vice-Chair, University of California San Diego, San Diego, California. eUniversity of Texas Health Science Center at Houston and McGovern Medical School, Houston, Texas; American Gastroenterological Association. fBoston University Medical Center, Boston, Massachusetts. gH. Lee Moffitt Cancer Center and Research Institute, Tampa, Florida. hPRiSMA Proctology Surgical Medicine & Associates, Houston, Texas; American College of Surgeons. iVirginia Tech Carilion School of Medicine, Roanoke, Virginia. jMassachusetts General Hospital, Boston, Massachusetts. kCleveland Clinic, Cleveland, Ohio. lSutter Medical Group, Sacramento, California. mDuke University Medical Center, Durham, North Carolina. nUniversity of Alabama at Birmingham, Birmingham, Alabama. oUniversity of California San Diego, San Diego, California. pUniversity of California San Francisco, San Francisco, California. qEmory University, Atlanta, Georgia, Primary care physician. rSpecialty Chair, Virginia Commonwealth University Medical Center, Richmond, Virginia.


Staging of Colorectal Cancer

Staging of Colorectal Cancer. The American College of Radiology seeks and encourages collaboration with other organizations on the development of the ACR Appropriateness Criteria through representation of such organizations on expert panels. Participation on the expert panel does not necessarily imply endorsement of the final document by individual contributors or their respective organization.


Staging of Colorectal Cancer

Staging of Colorectal Cancer. Reprint requests to: publications@acr.org


Staging of Colorectal Cancer

Staging of Colorectal Cancer

Staging of Colorectal Cancer. Staging of Colorectal Cancer


Staging of Colorectal Cancer

Staging of Colorectal Cancer. Colon Cancer The local treatment of colon cancer relies primarily on the section of involved colon (right versus left hemicolectomy), with removal of the associated mesentery and regional nodes. Use of selective adjuvant chemotherapy is dictated by lymph node positivity and extramural lymphovascular invasion on pathologic specimen. The role of preoperative imaging to predict T stage and N stage is an area of ongoing investigation, given that neoadjuvant therapy has not yet been shown to significantly improve survival over surgery alone (with postoperative adjuvant treatment) and the standard surgical approach is radical resection. Current ongoing trials including the large randomized controlled FOxTROT trial suggest that neoadjuvant treatment can preoperatively downstage colorectal cancer with better tolerated and more complete administration of chemotherapy before surgery rather than postoperative [15]. However, preoperative imaging of colon cancer appears to be of most benefit in identifying distant metastases, regardless of its ability to predict T stage and N stage. Given the limited role of locoregional staging, the imaging variant discussion for colon cancer will be limited to evaluation of distant metastases only.


Staging of Colorectal Cancer

Staging of Colorectal Cancer. Special Imaging Considerations In rectal tumors, because of the need for high-resolution anatomic detail in determining local tumor extension, the local staging of the tumor is often considered separately from the evaluation of distant metastatic disease, resulting in the need for a combination of modalities to fully stage the patient. In contrast, locoregional staging by imaging is not an issue for colon (nonrectal) cancers, and thus only the evaluation of distant metastatic disease is required.


Staging of Colorectal Cancer

Staging of Colorectal Cancer. OR Discussion of Procedures by Variant Variant 1: Rectal cancer. Locoregional staging. Initial imaging. In this clinical scenario, a patient has been recently diagnosed with rectal cancer and presents for evaluation of local regional extent of the rectal cancer to determine if the person would benefit from neoadjuvant therapy before possible surgical resection. This variant excludes (nonrectal) colon cancers.


Staging of Colorectal Cancer

Staging of Colorectal Cancer. For lymph node involvement, CT remains relatively nonspecific for N-stage determination. There is little agreement on the critical cut-off diameter to determine if lymph nodes are involved in the disease process. One study suggests 4.5 mm; however, nodal size is not seen as a predictor of nodal status at surgery [8,23]. Because detection of nodes involved with tumor remains a difficult problem, if a colonic resection is planned, local node groups should be encompassed in a properly performed cancer operation. Accuracies for CT detection of lymph node stage range from 56% to 84% [19,20,24-26]. Locoregional staging is not routinely performed for colon cancer; however, CT is


Staging of Colorectal Cancer

Staging of Colorectal Cancer. Staging of Colorectal Cancer still useful in the initial evaluation of all patients scheduled for colorectal carcinoma surgery because of its ability to obtain a rapid global evaluation and demonstrate potential complications of the tumor (eg, perforation, obstruction) that may not be clinically apparent [18].