The urinary bladder is a hollow, muscular organ in the pelvis that stores urine produced by the kidneys until it is ready to be expelled from the body through urination. On ultrasound, a full bladder appears as a large, well-defined, anechoic structure in the pelvis, and a distended bladder serves as an excellent acoustic window for transabdominal imaging of the uterus, ovaries, and prostate. Sonographers evaluate the bladder for wall thickening, masses, stones, and diverticula, and commonly measure the post-void residual volume to assess how completely a patient can empty their bladder. Bladder ultrasound is a routine part of both pelvic and renal examinations.
Sonography Term