mesane

The mesane, in Turkish medical terminology, is the urinary bladder, a hollow, distensible muscular organ that stores urine before it is excreted through the urethra. In adult anatomy, it sits in the pelvis, behind the pubic bone, and varies in size as it fills and empties.

Its wall comprises an inner mucosa, a thick middle layer of smooth muscle (the detrusor), and an adventitia or serosa. The bladder has a triangular area called the trigone, formed by the openings of the two ureters and the urethral outlet. In men it lies anterior to the rectum and superior to the prostate; in women it lies anterior to the vagina and uterus. Normal capacity is roughly 400–600 mL; the urge to void typically arises around 150–300 mL.

During storage, the detrusor muscle relaxes while the internal sphincter remains closed; external urethral sphincter provides voluntary control via the pudendal nerve. When voiding begins, parasympathetic signals from the pelvic nerves trigger detrusor contraction and sphincter relaxation, allowing urine to pass through the urethra.

Common conditions affecting the mesane include cystitis (bladder infection), bladder stones, bladder cancer (often urothelial carcinoma), overactive bladder with urgency and incontinence, stress incontinence, and neurogenic or obstructive bladder disorders. Diagnosis combines history, urinalysis, imaging (ultrasound or CT), and cystoscopy or urodynamic testing as needed. Treatments range from antibiotics for infections and antimuscarinic or beta-3 agonist medications for overactive bladder to catheterization or surgery for retention or tumors. The mesane plays a key role in urinary continence and the regulation of urine storage and release.