Urinary Bladder

Upper Surface

Inferolateral surfaceInferolateral surface

Apex

Neck

URINARY BLADDER

SHAPE: • It has the shape of three-sided pyramid

placed on one of its angles, with the apex of pyramid is directed forward & its base is directed backward

SITE: • It lies behind the body of pubis & is

separated from it by the retropubic space

MALE PELVIS

MALE PELVIS

BASE OF MALE BLADDER

FEMALE PELVIS

FEMALE PELVIS

URINARY BLADDER

RETROPUBIC SPACE: • It is a space filled with extraperitoneal

fatty tissue continuous with that of lower part of anterior abdominal wall

• It accomodates distention of urinary bladder

• In case of rupture of urinary bladder, urine may escape upward into the anterior abdominal wall

URINARY BLADDER

APEX:

• Is directed forward

• Is related to upper border of symphysis pubis

• Is connected to umbilicus by the median umbilical ligament (obliterated part of urachus)

URINARY BLADDER

BASE (POSTERIOR SURFACE):• Is directed backward• Its superolateral angles receive the ureters• In male: 1. Its upper part is covered by peritoneum2. It is related to vasa deferentia & seminal

vesicles separating it from rectum• In female:1. It has no peritoneal covering2. It is related to vagina

URINARY BLADDER

SUPERIOR SURFACE:

• Is covered by peritoneum in both sexes

• In male: it is related to sigmoid colon & loops of ileum

• In female: it is related to the uterus separating it from sigmoid colon & loops of ileum

URINARY BLADDER

INFEROLATERAL SURFACES:

• Are related to retropubic fat separating them from:

1. Body of pubis

2. Levator ani

3. Obturator internus

URINARY BLADDER

NECK:• Is the lowest & most fixed part• Lies behind symphysis pubis• Is continuous with urethra• In male:1. It rests on upper surface of prostate2. Anteriorly: it is attached to puboprostatic ligament3. Posteriorly: it is related to beginning of ejaculatory

ducts• In female:1. Anteriorly: it is attached to pubovesical ligament2. Posteriorly: it is related to anterior wall of vagina

URINARY BLADDER

LIGAMENTS:1. Median umbilical ligament2. Puboprostatic (pubovesical) ligament:• Forms the floor of retropubic space• In male: is called “puboprostatic” &

extends from body of pubis to prostatic fascia & neck of bladder

• In female: is called “pubovesical” & extends from body of pubis to neck of bladder

INTERIOR OF URINARY BLADDER

INTERIOR OF URINARY BLADDER• The mucous membrane forms folds (rugae)

that disappear when the bladder is distended• TRIGONE: 1. A triangular area in the base of bladder,

bounded by the 2 ureteric orifices & the internal urethral orifice

2. Its mucous membrane is elastic, more vascular & more sensitive

• UVULA VESICA: is an elevation immediately behind internal urethral orifice produced by the underlying median lobe of prostate

URINARY BLADDER

Distended Empty

URINARY BLADDER

CAPACITY: • Is about 300 ml with a maximum

capacity of 500 ml• Distended bladder:• Is circular in shape• Bulges upward into abdominal cavity• Removes peritoneum form lower part of

anterior abdominal wall & becomes into direct contact with it

URINARY BLADDER IN CHILD

• It is an abdominal organ even when empty

• It begins to enter the enlarging pelvis at six years of age

• It is not entirely a pelvic organ till after puberty

Median sagittal section of a new-born female child

URINARY BLADDER

ARTERIAL SUPPLY:

• Superior & inferior vesical arteries

VENOUS DRAINAGE:

• Veins from the vesical venous plexus that drain into the internal iliac vein

LYMPHATIC DRAINAGE:

• Into internal & external iliac lymph nodes

URINARY BLADDER• NERVE SUPPLY1. Parasympathetic fibers: from S2,3,4 motor

to detrusor muscle (muscle coat of bladder) & inhibitory to internal urethral sphincter, produce micturation.Pelvic splanchic nerve and inferior hypogastric nerve.

2. Sympathetic fibers: from first & second lumbar ganglia : by hypogastric plexuses

3. Ascending sensory fibers: carry sensation of fullness (distention) & pain sensation