Skip to main content
Urinary Bladder, prostate and urethra
Mr. M. Banda
4/24/2023 1
Urinary Bladder
• Introduction:
- Is a reservoir of urine
- Size, shape, position and
relations vary according
to content and state of
neighbouring viscera
- When empty: entirely in
lesser pelvis
- When full:
anterosuperiorly in
abdominal cavity
4/24/2023 2
Urinary Bladder
- Empty bladder: tetrahedral in shape
Base (fundus): directed backwards
Neck: lowest/fixed part
Apex: directed forwards
 3 surfaces: superior, Rt/Lt inferolateral
surfaces
4 borders: 2 lateral, one anterior and one
posterior
4/24/2023 3
Urinary Bladder
4/24/2023 4
Relations of Urinary Bladder
Base:
• Females:
- Uterus separating
it from rectum
4/24/2023 5
Relations of Urinary Bladder
Base:
• Males:
- Rectum separated
from it by:
 Rectovesical pouch
anteriorly
 Seminal vesicle and
vas deferens on each
side
 Denonvillier’s fascia
4/24/2023 6
Relations of Urinary Bladder
• Neck:
- Lies most inferiorly
- 3–4 cm behind symphysis pubis
- Is above plane of inferior aperture of lesser pelvis
- Essentially internal urethral orifice
- In males, rests on base of the prostate
- In females, related to pelvic fascia
4/24/2023 7
Relations of Urinary Bladder
• Apex:
- Both sexes faces towards upper part of the
symphysis pubis
- Median umbilical ligament (urachus) ascends
behind anterior abdominal wall from apex to
umbilicus
- Ligament covered by peritoneum to form the
median umbilical fold
4/24/2023 8
4/24/2023 9
4/24/2023 10
Relations of Urinary Bladder
Anterior surface:
- Separated from transversalis fascia by fat in
retropubic space (of Retzius)
Inferolateral surface:
- In males, anteriorly to pubis and puboprostatic
ligaments
- In females, relations are similar except that
pubovesical ligaments replace the puboprostatic
ligaments
- Inferolateral surfaces are not covered by peritoneum
4/24/2023 11
Relations of Urinary Bladder
Superior surface:
- In males, completely covered by peritoneum
- Rectovesical pouch separates it from rectum
- Sigmoid colon and terminal coils of the ileum
- In females, superior surface is largely covered by
peritoneum
- Reflected posteriorly onto the uterus to form
vesicouterine pouch
- Posterior part of the superior surface is devoid of
peritoneum
4/24/2023 12
Ligaments of the Bladder
• Attach bladder to pubis, lateral pelvic side-walls, and
rectum
True ligaments:
1. Pubovesical ligaments
2. Pubourethral ligaments
3. Puboprostatic (medial/lateral)ligaments in male
4. Median umbilical ligament
5. Lateral true ligament in male
6. Posterior vesical ligaments in male
4/24/2023 13
Ligaments of the Bladder
4/24/2023 14
Ligaments of the Bladder
4/24/2023 15
Ligaments of the Bladder
False ligaments:
1. Median umbilical fold
2. Two medial umbilical folds
3. Lateral false ligament
4. Posterior false ligament
4/24/2023 16
Bladder Interior
Vesical mucosa
• Almost all is attached loosely
to subjacent muscle
• Folds when the bladder
empties
• Folds stretched flat as it fills
• Over trigone, is adherent to
the subjacent muscle layer
and mucosa is always smooth
4/24/2023 17
Bladder Interior
• Trigone is formed by:
- Anteroinferior angle: internal urethral orifice
- Posterolateral angles: ureteric orifices
- Superior trigonal boundary has interureteric bar
• Trigone consists of 2 distinct layers:
- Superficial trigonal muscle
- Deep trigonal detrusor muscle
4/24/2023 18
4/24/2023 19
Bladder Interior
• Ureteric orifices
- Are placed at posterolateral trigonal angles
- In empty bladders: 2.5 cm apart, and 2.5 cm from
the internal urethral orifice
- Bladder distension: measurements may be
doubled
• Internal urethral orifice
- Is sited at the trigonal apex
- Lowest part of the bladder
4/24/2023 20
Capacity of Bladder
• Mean capacity: 220 mL
• Varies from 120-320 mL
• Filling beyond 220 mL causes desire to micturate
• Filling up to 500mL maybe tolerated but beyond
that it becomes painful
• Referred pain is felt in lower anterior abdominal
wall, perineum, penis (T11 to L2; S2-S4)
4/24/2023 21
Vascular Supply and Lymphatic Drainage of Bladder
• Arteries
- Principally by superior and inferior vesical arteries
- Supplemented by obturator and inferior gluteal
arteries
- In female: branches of uterine and vaginal arteries
• Veins
- Vesicle venous plexuses on inferolateral surfaces
drain into internal iliac veins
• Lymphatics
- External iliac nodes
4/24/2023 22
Nerve Innervation of the Urinary Bladder
• Both autonomic and somatic
Efferent nerves:
1. Parasympathetic efferent fibres (S2-S4):
- Motor to detrusor muscle
- Inhibitory to sphincter vesicae (internal sphincter)
- If these are destroyed, normal micturition is not
possible
2. Sympathetic efferent fibres (T10-L2):
- Inhibitory to detrusor muscle
- Motor to sphincter vesicae
4/24/2023 23
Nerve Innervation of the Urinary Bladder
3. Somatic: Pudendal nerve (S2-S4)
- Supplies the voluntary sphincter urethrae
(external sphincter)
Afferent nerves:
- Pain sensations pass via mainly the
parasympathetic and partly via sympathetic
nerves
- In spinal cord, pain pass via lateral spinothalamic
tract and awareness of bladder distension via
posterior columns
4/24/2023 24
Innervation of the Bladder
• Dashed lines indicate
sensory nerves
• Parasympathetic
innervation is shown at
the left
• Sympathetic at the upper
right
• Somatic at the lower right
4/24/2023 25
Male Urethra
• Is 18–20 cm long
• From internal urethral orifice in urinary bladder to
external opening, or meatus
• Two parts:
1. Anterior urethra (16 cm)
- Bulbar
- Pendulous or penile
2. Posterior urethra (4 cm)
- Preprostatic
- Prostatic
- Membranous
4/24/2023 26
Male Urethra
4/24/2023 27
4/24/2023 28
Vascular, lymphatic drainage and innervation of male urethra
Vascular supply:
Artery:
- Urethral artery, a branch of internal pudendal
artery
Veins:
- Dorsal veins of penis and internal pudendal veins
- These drain to prostatic plexus
- Posterior urethra drains into prostatic and vesical
venous plexuses, which drain into the internal iliac
veins
4/24/2023 29
Vascular, lymphatic drainage and innervation of male urethra
Lymphatic drainage
- Posterior urethra: internal iliac nodes
- Anterior urethra: accompany that of glans, then deep
inguinal
Innervation:
- Prostatic plexus supplies smooth muscle of prostate
and prostatic urethra
- Greater cavernous nerves carry sympathetic supply for
contraction of preprostatic sphincter during ejaculation
and prevents reflux of ejaculate into the bladder
4/24/2023 30
Vascular, lymphatic drainage and innervation of male urethra
• Parasympathetic preganglionic fibres are axons
from neurones in S2-S4 sacral spinal segments
• Nerve supply to external urethral sphincter is the
neurones in Onuf’s nucleus and by perineal
branches of pudendal nerve
4/24/2023 31
Female Urethra
• Is approximately 4 cm long and 6 mm in diameter
• Begins at internal urethral orifice of bladder, runs
anteroinferiorly behind symphysis pubis
• Is embedded in anterior wall of the vagina
• Ends at external urethral orifice in vestibule as an
anteroposterior slit
• Many small mucous urethral glands open into
urethra
• At lower end of urethra, Skene’s glands open into
para-urethral duct
4/24/2023 32
Female Urethra
4/24/2023 33
Female Urethra
Vascular Supply and Lymphatic Drainage
• Artery
- Internal pudendal artery via the urethral artery is the
principal supply
• Veins
- Urethral venous plexus drains into vesical venous
plexus around bladder neck, and into internal
pudendal veins
• Lymphatic drainage
- Internal and external iliac nodes
4/24/2023 34
Female Urethra
• Innervation
- Parasympathetic preganglionic fibres: S2-S4 pelvic
splanchnic nerves
- Postganglionic fibres: smooth muscle of the
urethral wall
- Somatic fibres to the striated muscle: S2 to S4
- Postganglionic sympathetic fibres arise from
plexus around vaginal arteries
4/24/2023 35
Histology of Urinary Bladder and Urethra
4/24/2023 36
Prostate gland
• Is a pyramidal fibromuscular
accessory gland
• Surrounds prostatic urethra from
bladder base to the membranous
urethra
• Unlike the thyroid gland, its
neurovascular bundle lies between
the true and the false capsules
• During prostatectomy, the
neurovascular tissue is preserved
to avoid damage to the prostatic
plexus which is a component of
the inferior hypogastric plexus
(autonomic)
• Damage to prostatic plexus can
cause erectile dysfunction
4/24/2023 37
Prostate gland
• Numerous fibromuscular septa which divide
glandular tissue into indistinct lobules
• Muscular tissue within prostate is mainly smooth
muscle
• In female, prostate is represented by paraurethral
glands of Skene
4/24/2023 38
Prostate gland
• Size and weight:
- Measures:
 4cm transversely at base
2 cm anteroposterior diameter
3 cm vertical diameter
- Weight varies:
Average of 8g in youth
In BPH: 40-150 g
4/24/2023 39
Prostate Gland
• Blood supply:
Arteries: branches from
- Inferior vesical
- Middle rectal
- Internal pudendal
Veins:
- Prostatic venous plexus communicate with vesical
plexus and internal iliac veins
- Communicates with Batson’s plexus of veins via which
prostate carcinoma can spread
4/24/2023 40
Prostate Gland
• Lymphatic drainage:
- Internal iliac nodes
- Sacral nodes
- Partly external iliac nodes
• Nerve supply:
- Autonomic via the prostatic plexus which comes
from inferior hypogastric plexus
4/24/2023 41
Zonal Anatomy of the Prostate
• Anatomically; glandular tissue is subdivided into
three distinct zones:
- Peripheral (70% by volume)
- Central (25% by volume)
- Transitional (5% by volume)
• Non-glandular tissue (fibromuscular stoma) fills up
space between peripheral zones anterior to the
preprostatic urethra
4/24/2023 42
Zonal Anatomy of the Prostate
4/24/2023 43
Zonal Anatomy of the Prostate
4/24/2023 44
Zonal Anatomy of the Prostate
4/24/2023 45
Zonal Anatomy of the Prostate
4/24/2023 46
Histology of the Prostate Gland
• Epithelium: pseudostratified columnar
• Has tubuloalveolar glands
• Rich fibromuscular stroma surrounds the
glands
• Is surrounded by fibroelastic capsule rich in
smooth muscle
• Septa from capsule penetrate gland and divide
it into lobes that are indistinct in adult men
4/24/2023 47
Histology of the Prostate Gland
• Has small spherical bodies of glycoproteins, 0.2-2
mm in diameter and often calcified
• Are called prostatic concretions, or corpora
amylacea
• Their significance is not understood, but their
number increases with age
• Prostatic secretions are slightly acid, and contain
acid phosphatase, amylase, Prostate-specific
Antigen (PSA), fibrinolysin and zinc
4/24/2023 48
Histology of the Prostate Gland
4/24/2023 49
The End
Thank you!
4/24/2023 50