Kidney cysts

Diagnostic Evaluation

Renal cysts may be congenital or acquired and can impair concentrating ability or contribute to infection or rupture. Imaging aims to characterize cysts, differentiate them from solid masses, and assess kidney function-related changes. Ultrasound is usually first because it differentiates cystic versus solid components and evaluates hydronephrosis. CT best characterizes complex cysts, wall enhancement, and associated lesions. Radiographs are limited unless there are gross abnormalities. MRI can further characterize complicated lesions. Nuclear studies assess functional contribution when needed.