Which imaging procedure is commonly used to diagnose upper urinary tract obstruction or stones?

• A. CT urography
• B. Barium swallow
• C. MRI urography
• D. Chest CT

Answer: (D)

Evaluating upper urinary tract obstruction or stones requires an imaging test that can clearly show the kidneys, ureters, and collecting system while also detecting calcifications. CT urography fits this need best because it combines detailed cross-sectional imaging with contrast phases that outline the urinary tract, revealing stones, hydronephrosis, and the cause of blockage. In practice, a non-contrast CT is extremely sensitive for detecting renal calculi, and when obstruction or detailed anatomy is suspected, CT urography with contrast-enhanced excretory imaging is commonly used. Options like barium swallow or chest CT do not evaluate the urinary tract, and MRI urography, while useful in some scenarios, is not the routine first-line test for acute stone or obstruction assessment.