left lateral wall of urinary bladder

The left lateral wall of the urinary bladder is the left-sided lateral wall of the bladder, forming the left flank of the organ and facing the left pelvic sidewall, adjacent to left pelvic structures including the left ureter, left obturator complex, and left seminal vesicle in males.

The left lateral wall of the urinary bladder is adjacent to the left obturator internus muscle and fascia, the left obturator nerve and vessels, the left ureter as it courses toward the bladder, and in males the left seminal vesicle and left vas deferens posterolaterally. The left medial umbilical ligament courses along this surface.

The left ureter descends from the left kidney, crosses the left common iliac artery bifurcation, and enters the pelvis, running medial to the left internal iliac vessels. It approaches the posterolateral aspect of the bladder wall and traverses the bladder wall obliquely, entering at the left ureteral orifice on the trigone. In females, the ureter passes under the uterine artery near this region.

The left lateral wall of the bladder drains to the left external iliac, left internal iliac, and left obturator lymph nodes. During radical cystectomy, bilateral pelvic lymph node dissection includes nodes from both the left and right lateral chains. Metastases to left lateral nodes from left-sided bladder tumors indicate at least pN1 disease.

The right and left lateral walls of the urinary bladder are generally symmetrical in anatomy, but there may be asymmetry in the position of ureteral orifices, especially in cases of duplex ureters or ectopic ureteral insertion. Additionally, adjacent structures such as the sigmoid colon on the left side may create different anatomic relationships during pelvic surgery on each side.