Retroperitoneal Ultrasound

Retroperitoneal ultrasound is covered as a reasonable and necessary imaging modality for diagnosis and management of retroperitoneal organs including pancreas, abdominal aorta (including aortic aneurysm follow-up), inferior vena cava, kidneys (scarred/small kidneys, renal cysts, solid masses, suspected renal disease), ureteral obstruction, bladder (intraluminal tumors, wall assessment, post-void residual), renal transplants, prostate via transrectal US, and traumatic injury to retroperitoneal organs. Limitations include poor utility for vesicular ureteral reflux, limited sensitivity for early/mild renal cortical disease and normal ureters (especially mid-portions), and preference for CT over US for adenopathy and adrenal evaluation; bladder tumor surveillance is most efficient with cystoscopy/urography. The policy defines complete versus limited studies but does not specify numeric frequency limits or required claim documentation; renal transplant imaging frequency should be driven by signs and symptoms.