This document provides an overview of the anatomy of the urinary bladder, including its embryology, gross anatomy, histology, vascular and nerve supply, and surgical considerations. It describes the bladder's location in the pelvis, layers, relationships to surrounding organs, and changes during filling and voiding. Key structures like the trigone and bladder neck are emphasized. Modulators of bladder function from the brain and spinal cord through peripheral nerves are reviewed.

1. ANATOMY OF
URINARY BLADDER
Dept of Urology
Govt Royapettah Hospital and Kilpauk Medical College
Chennai

2. Moderators:
Professors:
• Prof. Dr. G. Sivasankar, M.S., M.Ch.,
• Prof. Dr. A. Senthilvel, M.S., M.Ch.,
Asst Professors:
• Dr. J. Sivabalan, M.S., M.Ch.,
• Dr. R. Bhargavi, M.S., M.Ch.,
• Dr. S. Raju, M.S., M.Ch.,
• Dr. K. Muthurathinam, M.S., M.Ch.,
• Dr. D. Tamilselvan, M.S., M.Ch.,
• Dr. K. Senthilkumar, M.S., M.Ch.
Dept of Urology, GRH and KMC, Chennai. 2

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Dept of Urology, GRH and KMC, Chennai.

4. EMBRYOLOGY
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Dept of Urology, GRH and KMC, Chennai.

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Dept of Urology, GRH and KMC, Chennai.

9. GROSS ANATOMY
• Extraperitoneal hollow organ in
anterior pelvis
• When filled, the bladder has a
capacity of about 500 mL - ovoid
shape.
• The empty bladder is tetrahedral
• a superiorsurface with an apex at
the urachus
• two inferolateralsurfaces
• a posteroinferior surface or base
with the bladder neck at the lowest
point
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Dept of Urology, GRH and KMC, Chennai.

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Dept of Urology, GRH and KMC, Chennai.

11. • Retzius Space – retro pubic
prevesical space
• Contains loose areolar tissue
• Cushion for anteriorbladder
• Enteredby dividing the
transversalis fascia
• As far posteriorlyas iliac vessels
and distal ureter
• For open prostatectomy, anterior
bladder and pelvic fractures.
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Dept of Urology, GRH and KMC, Chennai.

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Dept of Urology, GRH and KMC, Chennai.

13. Urinary bladder
• Male.
• Fundus is directed caudally and posteriorly.
• Separated from Rectum by - Rectovesical septum, seminal
vesicles, and ampulla of vas deferens
• Apex is directed toward pubic symphysis, with Median umbilical
ligament (urachus) continued up to abdominal wall to umbilicus.
• Superiorly covered by peritoneum & related to sigmoid colon and
ileum coils.
• Inferior lateral surface is separated from pubis by a prevesical
cleft space of Retzius.
• Neck is triangular, in contact with base of prostate, contains
urethral orifice.
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Dept of Urology, GRH and KMC, Chennai.

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Dept of Urology, GRH and KMC, Chennai.

16. Urinary bladder
• Female
• Fundus is separated from
anterior surface of uterus
by VesicoUterine pouch.
• Below, is related to cervix
and upper vaginal wall.
• Superior surface, when
bladder is empty, uterus
rest on this.
• Inferior surface, rest on
pelvic and urogenital
diaphragm.
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Dept of Urology, GRH and KMC, Chennai.

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Dept of Urology, GRH and KMC, Chennai.

18. • Body (or dome) and Fundus :
- supple, mobile and highly
distensible -
capable of expanding into
abdomen
• Base of bladder not so
distensible holds orifices (ureters
and urethra) in place
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Dept of Urology, GRH and KMC, Chennai.

19. Peritoneal Reflection
• Superior surface
• Ant – Sweeps onto the ant abd wall
• Post – passes to level of SV
• On distension,it sweeps off the ant
abd wall superiorly
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Dept of Urology, GRH and KMC, Chennai.

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25. HISTOLOGY
• 7 layers of urothelium
• GAG coat
• Thin BM
• Thick Lamina Propria with blood
vessels
• Smooth muscle layer
• inner longitudinal,
• middle circular
• outer longitudinal layers
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Dept of Urology, GRH and KMC, Chennai.

29. Male Bladder Neck
• The large-diameter muscle fascicles replaced by much finer fibers
• bladder neck  the detrusor muscle - three layers
• Radially oriented inner longitudinal fibers pass through the internal
meatus to become continuous with the inner longitudinal layer of
smooth muscle in the urethra.
• The middle layer forms a circular preprostatic sphincter
that is responsible for continence at the level of the bladder neck
• The outer longitudinal fibers are thickest posteriorly
at the bladder base and attached to the apex of trigone and prostate
Bladder neck plays important role in antegrade ejaculation.
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Dept of Urology, GRH and KMC, Chennai.

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Dept of Urology, GRH and KMC, Chennai.

31. Female neck
• At the female bladder neck, the inner longitudinal fibers converge
radially to pass downward as the inner longitudinal layer of the
urethra.
• Middle layer not so robust
• Little adnergic innervation and is weak
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Dept of Urology, GRH and KMC, Chennai.

32. UV junction
• 2 to 3 cm from the bladder,
Waldeyer fibromuscular
sheath extends longitudinally
over the ureter and follows it
to the trigone.
• Intramural 1.5-2 cm
• The intravesical portion lies
immediately beneath the
bladder urothelium  pliant
• backed by a strong plate of
detrusor muscle
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Dept of Urology, GRH and KMC, Chennai.

33. • Intramural ureter is a common site in which ureteral stones are
impacted.
• Pliant intravesical ureter backed by a strong plate of detrusor results
in passive occlusion of ureter like a flap valve ,VUR is thought to
result from insufficient submucosal length of ureter and poor
detrusor backing.
• Chronic increasing intravesical pressure due to BOO cause herniation
of bladder mucosa through weakest point of hiatus above the ureter
and produce a Hutch diverticulum and reflux.
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Dept of Urology, GRH and KMC, Chennai.

34. Special feature
•Trigone of the bladder:
• A smooth triangular area
above the urethral
orifice.
• Posterolateral angles are
formed by the Ureteric
orifice
• Base is formed by the
interureteric
ridge(Mercier) between
the orifices
• Anterior angle is at the
internal urethral orifice.
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Dept of Urology, GRH and KMC, Chennai.

35. Trigone
• The muscle of trigone forms three distinct layers:
(1)a superficial layer, derived from the longitudinal muscle of the
ureter, which extends down the urethra to insert at the
verumontanum;
(2) a deep layer, which continues from Waldeyer sheath and inserts
at the bladder neck;
(3) a detrusor layer, formed by the outer longitudinal and middle
circular smooth muscle layers of the bladder wall.
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Dept of Urology, GRH and KMC, Chennai.

37. • Superficial trigonal muscle anchors the ureter to the bladder.
• During ureteral reimplantation, this muscle is tented up and divided
in order to gain access to the space between Waldeyer sheath and
the ureter
• The urothelium overlying the muscular trigone is usually only three
cells thick  adheres strongly to the underlying muscle by a dense
lamina propria.
• During filling and emptying of the bladder, this mucosal surface
remains smooth.
• Trigone relaxes during Micturition phase
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Dept of Urology, GRH and KMC, Chennai.

38. NEUROVASCULAR SUPPLY
•Arteries: superior and inferior vesical, middle rectal
•Veins: vesical plexus  vesical veins internal iliac
vein (communicates with prostatic plexus)
•Lymphatics: External(Bulk), internal, sacral, and
common iliac nodes,obturator nodes.
•Nerves: Inferior epigastric and vesical plexus
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Dept of Urology, GRH and KMC, Chennai.

39. 1.Superior vesical artery :
-supplies the superior part of bladder
2.Inferior vesical artery:
-supplies the lower ureter ,bladder base , prostate
and the seminal vesical in male
-in female supply the ureter ,bladder base and
vagina
3.Trigone is mainly supplied by
-vesiculo-deferential artery in male
-uterine artery in female
4.Additional supply is derived from
-obturator
-inferior gluteal
-in females-uterine and vaginal arteries 39
Dept of Urology, GRH and KMC, Chennai.

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Dept of Urology, GRH and KMC, Chennai.

41. VASCULATURE OF BLADDER :
Vesical blood supply is through two pedicles
1. Lateral pedicle 2. Posterior pedicle
1. LATERAL PEDICLE:
- formed mainly by lateral vesical ligament in male
cardinal ligament in
female
(approached from rectovesical space it lies lateral to ureter
2. POSTERIOR PEDICLE:
- formed by posterior vesical ligament in male,
uterosacral ligament in female (posteromedial to ureter)
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Dept of Urology, GRH and KMC, Chennai.

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Dept of Urology, GRH and KMC, Chennai.

43. VENOUS DRAINAGE:
* the dorsal vein of penis passes between the
inferior pubic arch and the striated urinary
sphincter to reach the pelvis
* it trifurcates into
1. central superficial branch
2. 2 lateral plexuses (plexus of santorini)
[During retropubic prostatectomy the dorsal
vein complex is best divided distally before its
ramification to minimise blood loss.]
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Dept of Urology, GRH and KMC, Chennai.

44. * The superficial branch pierces the visceral endopelvic
fascia between the puboprostatic ligaments draining
1. retropubic fat
2. anterior bladder
3. anterior prostate
* Lateral plexuses swifts down the side of the prostate
receiving drainage from prostate & rectum
*communicates with vesical plexuses on the lower
part of bladder
*3-5 inferior vesical veins emerge from vesical plexuses
and drains into internal iliac veins
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Dept of Urology, GRH and KMC, Chennai.

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Dept of Urology, GRH and KMC, Chennai.

46. LYMPHATIC DRAINAGE
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Dept of Urology, GRH and KMC, Chennai.

48. Neurogenic control
• Brain:
- Master control
- Conscious social control
- Frontal lobe
- Tonically inhibitory signals to detrusor.
- [Stroke,dementia,cancer, CP, parkinson, shy drager syndrome…. ]
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Dept of Urology, GRH and KMC, Chennai.

49. • Brain stem:
- Pons- PMC – Barington’s nucleus
- Inborn excitatory nature.
- As a relay switch in the voiding pathway.
- Coordinates the urethral sphincter relaxation and detrusor contraction
to facilitate urination.
- Affected by emotions.
- Brain takes over the control of the pons at age 3-4 years.
- The stretch receptors of the detrusor muscle send a signal to the pons,
which in turn notifies the brain.
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Dept of Urology, GRH and KMC, Chennai.

50. • Sacral spinal cord:
- Primitive voiding center – Sacral reflex center – bladder contractions.
- Important intermediary between the pons and the sacral cord.
- Spinal injury: urinary frequency, urgency and urge incontinence and are
unable to empty bladder. [Detrusor sphincter dyssynergia with detrusor
hyperreflexia (DSD-DH)].
( EX … multiple sclerosis).
- Or Detrusor areflexia. (Herniated disc/ tumor)
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Dept of Urology, GRH and KMC, Chennai.

51. • Peripheral nerves:
- Sympathetic: constantly active. [T10-L2].
1. Bladder to increase its capacity without increasing detrusor resting
pressure (accommodation) and stimulates the internal urinary sphincter to
remain tightly closed.
2.Sympathetic activity also inhibits para sympathetic stimulation [S2-4]
(opposite action).
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Dept of Urology, GRH and KMC, Chennai.

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Dept of Urology, GRH and KMC, Chennai.

54. • Somatic nervous system:
- External urinary sphincter and the pelvic diaphragm.
- Pudendal nerve [S2-3] originates from the nucleus of Onuf and regulates
the voluntary actions of the external urinary sphincter and the pelvic
diaphragm.
- Shy- Drager synd : Lesion in Onuf nucleus.
- Neuropraxia : after delivery- Stress incontinence.
- Suprasacral- infrapontine spinal cord trauma can cause overstimulation of
the pudendal nerve - urinary retention. SPINAL SHOCK
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Dept of Urology, GRH and KMC, Chennai.

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59. Bladder Afferent Fiber - Type Location
• Aδ (finely myelinated axons) (Smooth muscle) Sense bladder
fullness (wall tension) Increase discharge at lower pressure
threshold
• C fiber (unmyelinated axons) (Mucosa) Respond to stretch
(bladder volume sensors) Increase discharge at lower threshold
• C fiber (unmyelinated axons) (Mucosa muscle)
Nociception to overdistention -Sensitive to irritants
• Silent afferent
• Becomes mechanosensitive and unmasks new afferentpathway during
inflammation
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Dept of Urology, GRH and KMC, Chennai.

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Dept of Urology, GRH and KMC, Chennai.

61. Storage & voiding reflexes
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Dept of Urology, GRH and KMC, Chennai.

62. SURGICAL ANATOMY
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Dept of Urology, GRH and KMC, Chennai.

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Dept of Urology, GRH and KMC, Chennai.

64. To prevent impotence
following radical
cystectomy, the surgeon
should preserve the
autonomic plexus at the
pelvic side walls by staying
close to the seminal
vesicles.
Injury to the nerves
innervating the corpora
can be prevented by
locating the NV bundle
between the lateral pelvic
fascia and Denonvilliers'
fascia . 64
Dept of Urology, GRH and KMC, Chennai.

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Dept of Urology, GRH and KMC, Chennai.

66. THANK YOU...:)
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Dept of Urology, GRH and KMC, Chennai.