MRI Abdomen and Pelvis Without IV Contrast There is no relevant literature documenting the additional benefit of MRI without IV contrast without dedicated urographic imaging, relative to noncontrast MRU, in the pregnant patient for the evaluation of stones; however, it can be helpful in follow-up imaging for stones and/or hydronephrosis, particularly if US is limited. MRI Abdomen and Pelvis Without and With IV Contrast There is no relevant literature documenting the additional benefit of MRI without and with IV contrast, relative to noncontrast MRU, in the pregnant patient for the evaluation of stones. MRU Without and With IV Contrast There is no relevant literature documenting the additional benefit of MRU without and with IV contrast, relative to noncontrast MRU, in the pregnant patient for the evaluation of stones. MRU Without IV Contrast With a goal of avoiding irradiation of the fetus, MRU has also been advocated for the detection of ureteral calculi at some centers [48] as well as hydronephrosis or other cause of renal obstruction. However, in a study by Shokeir et al [49] in nonpregnant patients, the site of stone impaction was identified by noncontrast CT in 146 of 146 renal units (100% sensitivity) and by MRU in only 101 of 146 renal units (69% sensitivity). A survey of academic medical centers found that radiologists are more likely to image for suspected renal calculus with CT than with MR in the second (35% versus 20%) and third (48% versus 18%) trimesters [50]. Radiography Abdomen and Pelvis There is no relevant literature documenting the benefit of KUB in the pregnant patient for the evaluation of stones. Radiography Intravenous Urography Limited IVU (example: scout radiograph, film at 30 seconds and film at 20 minutes) has also been used to diagnose ureteral obstruction in pregnant patients [51].
Acute Onset Flank Pain Suspicion of Stone Disease Urolithiasis . MRI Abdomen and Pelvis Without IV Contrast There is no relevant literature documenting the additional benefit of MRI without IV contrast without dedicated urographic imaging, relative to noncontrast MRU, in the pregnant patient for the evaluation of stones; however, it can be helpful in follow-up imaging for stones and/or hydronephrosis, particularly if US is limited. MRI Abdomen and Pelvis Without and With IV Contrast There is no relevant literature documenting the additional benefit of MRI without and with IV contrast, relative to noncontrast MRU, in the pregnant patient for the evaluation of stones. MRU Without and With IV Contrast There is no relevant literature documenting the additional benefit of MRU without and with IV contrast, relative to noncontrast MRU, in the pregnant patient for the evaluation of stones. MRU Without IV Contrast With a goal of avoiding irradiation of the fetus, MRU has also been advocated for the detection of ureteral calculi at some centers [48] as well as hydronephrosis or other cause of renal obstruction. However, in a study by Shokeir et al [49] in nonpregnant patients, the site of stone impaction was identified by noncontrast CT in 146 of 146 renal units (100% sensitivity) and by MRU in only 101 of 146 renal units (69% sensitivity). A survey of academic medical centers found that radiologists are more likely to image for suspected renal calculus with CT than with MR in the second (35% versus 20%) and third (48% versus 18%) trimesters [50]. Radiography Abdomen and Pelvis There is no relevant literature documenting the benefit of KUB in the pregnant patient for the evaluation of stones. Radiography Intravenous Urography Limited IVU (example: scout radiograph, film at 30 seconds and film at 20 minutes) has also been used to diagnose ureteral obstruction in pregnant patients [51].