Pearls and pitfalls in sonographic imaging of symptomatic urolithiasis in pregnancy.

Symptomatic urolithiasis in the pregnant patient presents a diagnostic challenge to the clinician and radiologist. The presentation can mimic multiple other disease processes, including pathology unique to the gravid patient. The objective of this article was to describe challenges in sonographic imaging of urolithiasis in pregnant patients. Ultrasonography is the imaging modality of choice in pregnant patients with suspected urolithiasis. Signs of urinary collecting system obstruction that are usually reliable in nonpregnant patients may not be reliable in pregnant patients. Normal physiological changes of pregnancy can mimic ureteral obstruction on imaging. Utilization of endovaginal scanning techniques and intrarenal resistive index determination may help improve the diagnostic accuracy of ultrasound in symptomatic patients.