Sonography of benign renal cystic disease.

When evaluating renal cystic mass lesions, ultrasound plays an important part in distinguishing cysts from solid lesions and in demonstrating the complex internal architecture of cystic lesions. Ultrasound is usually the initial imaging modality for patients who have medical renal disease. When renal cystic disease is identified, it is extremely important to accurately communicate the findings and attempt to distinguish benign from surgical lesions.