Imaging studies commonly used to evaluate urinary tract problems include:

• A. Renal/bladder ultrasound only
• B. Non-contrast CT for stones
• C. MRI/CT urography as indicated
• D. Renal/bladder ultrasound; non-contrast CT for stones; MRI/CT urography as indicated; ultrasound is often first-line

Answer: (D)

A broad, practical approach to imaging urinary tract problems uses a combination of tests, chosen for safety, accuracy, and the specific clinical question. Renal/bladder ultrasound is often the first study because it’s noninvasive, lacks radiation, is quick and inexpensive, and can detect hydronephrosis, bladder issues, and gross anatomy problems. When a stone is suspected, non-contrast CT is preferred because it provides the highest sensitivity and specificity for detecting stones throughout the urinary tract, is fast, and doesn’t require contrast, which lowers risk for allergy or kidney injury. If the initial studies don’t fully explain the symptoms or if more detailed anatomy or functional information is needed, MRI urography or CT urography with contrast offers comprehensive evaluation of the kidneys, ureters, and bladder, including excretory function and subtle abnormalities. So using ultrasound first, adding non-contrast CT for stones, and reserving MRI or CT urography for indicated cases reflects the common, stepwise imaging strategy in urinary tract problems.