11 Urinary Tract

11 Urinary Tract

G. Schmidt

nels. They unite to form major calices, from which urine drains into the renal pelvis and thence to the ureter, bladder, and urethra.

Fig. 11.1 Acute suppurative pyelitis with pelvic dilatation and hypoechoic wall thickening (cursors).

prominent ureteral ridges that protrude into the bladder lumen (Fig.11.3).

The size of the bladder depends on its degree of distension. This also determines the shape of the bladder, which may appear round, squared with rounded corners, or elliptical (Fig.11.2). The wall thickness of the full bladder is 1–3 mm. An urge to urinate is felt when the bladder is filled to approximately 350 mL, but the bladder can easily accommodate twice that volume.

c Diagram showing the anatomy and relations of the bladder, seminal vesicles, urethra, and prostate.

Locations

●Ureteropelvic junction

●Ureter anterior to the iliac vessels

●Prevesical ureter

●Bladder in the lesser pelvis

Ureteropelvic junction and course of the ureter. The ureter leaves the renal hilum posterior to the renal vein and artery. Hence it is best to scan the ureter from behind with the ultrasound beam directed anteriorly (Fig.11.4, Fig.11.5). The ureter descends anteriorly to

Fig. 11.5 Course and relations of the ureter. a Proximal ureter.

the iliopsoas muscle, following the lordotic curvature of the lumbar spine. Initially it takes a steep anterior and inferomedial course, then turns distally toward the lateral border of the bladder. As it descends, it crosses over the iliac vessels at the level of the origin of the deep iliac artery, follows the wall of the lesser pelvis, and finally opens into the bladder at the laterobasal ureteral ridges (Fig.11.5).

Bladder. Figure 11.3 and Fig.11.6 illustrate the relations of the bladder to the organs of the lesser pelvis and to the male reproductive tract.

Fig. 11.4 Transverse scan of the right kidney (N). From anterior to posterior: the renal vein (V) followed by the renal artery (A) and upper ureter (U). L = liver.

fb Course from the renal pelvis to the bladder trigone. 1 = ureteropelvic junction area; 2 = ureter crossing over the iliac vessels; 3 = supravesical segment.