Urinary Bladder & Ureter😊

Urinary Bladder

Interior of Bladder

• Interureteric ridge = Bar of Mercier

• Ureterourethral ridge = Bell's bar

Nerve Supply

Sympathetic

• From T11 – L2

• Via hypogastric plexus
• (-) detrusor
• (+) IUS

Parasympathetic

• From S2, S3, S4

• Via pelvic splanchnic nerves
• (+) detrusor

Somatic

• Pudendal nerve (S2, S3, S4)

• Controls EUS

• ”Mneumonic: Pidich vakkunnath Pudendal N“

Pain and Sensory Tracts

• Pain sensation from bladder
• Lateral spinothalamic tract

• Awareness of distention
• Dorsal column tract
• Distension → Dorsal column

Clinical Note:

• For intractable pain
• Anterolateral bilateral cordotomy is done
• Desire to micturate remains (as dorsal column intact)

Urethra

Length

• Female: 3-4 cm.

• Male: 18-21 cm.

Parts

• Proximal: Membranous + Prostatic Urethra.

• Distal: Penile + Bulbar Urethra.

Epithelium of Male Urethra

Part	Notes
Pre-prostatic & Prostatic urethra	Transitional epithelium
Membranous urethra	Pseudostratified / Stratified columnar
Bulbar urethra	Most distensible part
Penile (Spongy) urethra	• Proximal → Pseudostratified columnar • Distal → Stratified squamous

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Transitional epithelium / urothelium lines

• Renal pelvis and calyces,

• ureter

• urinary bladder

• pre-prostatic & prostatic parts of the urethra

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Ureteric constrictions

ㅤ	ㅤ
Surgical constrictions	1 - 5
Anatomical constrictions	1, 2, 4
Narrowest Constriction	4 > 5