Urolithiasis, Obstructive Uropathy, and Hydronephrosis — WACS Viva & Clinical Scenarios (Genitourinary and Retroperitoneal Imaging)

Exam-style urolithiasis, obstructive uropathy, and hydronephrosis viva scenarios with examiner probes and model answers for Radiology candidates.

Scenarios covered

• SCENARIO 1: A 34-year-old male presents to the emergency department with severe, colicky right flank pain radiating to the groin and microscopic hematuria. Describe your imaging strategy, protocol selection for low-dose non-contrast computed tomography of the kidneys, ureters, and bladder (NCCT KUB), and the key secondary cross-sectional signs you would evaluate to establish acute ureteric obstruction.
• SCENARIO 2: A 22-year-old female undergoes Doppler ultrasonography and CT angiography for recurrent left flank dull aching pain aggravated by fluid intake. Cross-sectional imaging reveals severe left hydronephrosis terminating at the pelviureteric junction with a lower pole renal vessel traversing the anterior junction. Detail the radiological findings that distinguish congenital intrinsic ureteropelvic junction (UPJ) obstruction from extrinsic vascular compression, and outline the quantitative Doppler and parenchymal parameters required for surgical planning.
• SCENARIO 3: An axial NCCT KUB image displays a hyperdense 9 mm calculus in the proximal third of the right ureter with a mean attenuation value of 420 Hounsfield Units (HU) and an anterior abdominal wall skin-to-stone distance of 14 cm. Explain the diagnostic utility of CT attenuation values, dual-energy CT (DECT) post-processing, and anatomical metrics in predicting calculus chemical composition and selecting between medical expulsive therapy, extracorporeal shock wave lithotripsy (ESWL), and endourological intervention.
• SCENARIO 4: A 58-year-old diabetic female presents with right flank pain, high-grade fever, chills, and refractory hypotension. Renal ultrasound and contrast-enhanced CT demonstrate pelvicalyceal dilatation, echogenic non-dependent debris within the collecting system, urothelial enhancement, extensive perinephric fluid, and retroperitoneal fluid tracking into the right paracolic gutter. Formulate a structured radiological report establishing the distinction between uncomplicated hydronephrosis, obstructive pyonephrosis, and forniceal rupture, and state the urgent interventional radiologic procedures indic
• SCENARIO 5: A 28-year-old female at 24 weeks gestation presents with acute right loin pain. Discuss the diagnostic imaging algorithm, highlighting the safety profiles of ultrasound, non-contrast magnetic resonance urography (MRU), and low-dose CT, and describe the specific imaging features used to differentiate physiological hydronephrosis of pregnancy from acute pathological ureteric obstruction.