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PROSTATE GLAND
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I. Introduction/General Information
A. Attached inferiorly to urinary bladder by
ligaments
B. Posterior to pubic symphysis
C. Surrounds superior portion of urethraD. Anterior to rectum (palpation, ultrasound)
E. Conical shape
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Introduction, Prostate Gland, continued
F. Walnut sized
1. 4 cm trans x 2 cm A/P x 3 cm Sup/Inf
G. Lightly encapsulated
1. Fibrous connective tissue
2. Smooth muscle3. Capsule extends into lobes
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II. Prostate Gland: Detailed Anatomy
A. Largest male
accessory
gland
B. Located in
subperitoneal
compartment(between pelvicdiaphragm &
peritoneum)Prostate Gland, Mid-sagittal Section
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Prostate Gland: Detailed Anatomy
C. Enclosed in fascial sheath
(aka: prostatic sheath)
1. Inferiorly, sheath is continuous
with superior fascia of
urogenital diaphragm
2. Posteriorly, sheath forms part of
retrovesical septum
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Prostate Gland: Detailed Anatomy
D. Double Capsule
1. Fibrous portion contacts gland2. External capsule formed by pelvic
fascia
3. Venous plexus lies between
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Male Reproductive System, Posterior View
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Detailed Anatomy, contined
E. Conical shape with base (sup), apex (inf),
four surfaces
1. Surfaces: posterior, anterior, right &left inferolateral
2. Base (aka: vesicular surface): superior
a. Attached to neck of urinary bladder
b. Prostatic urethra enters middle of
base close to anterior surface
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Prostate Anatomy
Prostatic Urethra
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Detailed Anatomy, contined
3. Apex: inferiora. Rests on superior fascia of urogenital
diaphragm muscle
b. Associated with sphincter urethraec. Contacts medial margins oflevator ani
muscles
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Detailed Anatomy, contined
4. Posterior surface: triangular, flat
5. Anterior surface: narrow, convex
6. Inferiorolateral surfaces
a. Meet with anterior surface
b. Rest on levator ani fascia above
urogenital diaphragm
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Detailed Anatomy, contined
F. Lobes of the Prostate
1. Divisions are arbitrary, indistinct
2. Usually divided into
a. two lateral lobesb. one median lobe
c. anterior and posterior lobes
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Lobes of the Prostate, continued
3. Median lobe
a. Lies posterior and superior toprostatic utricle and ejaculatory
ducts
b. May project into urinary bladder
c. Utricle lies within lobe1. Vestigial remains of uterine
homolog
2. Sometimes called uterus
masculinis
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Lobes of the Prostate, continued
4. Lateral lobes
a. Comprise the greatest mass ofthe gland
b. Contain most secretory tissue
c. Are continuous posteriorly
5. Glandular tissue with varying amounts
of fibrous tissue
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Lobes of the Prostate, continued
Prostate Glandin situ
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Detailed Anatomy, continued
G. Blood & lymph
1. Arteries derived
from:
a. Internal pudendalartery
b. Inferior vesicalartery
c. Middle rectalartery
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Blood & Lymph, continued
2. Veins
a. Form venous plexusb. Drain into internal iliac veins
c. Communicate with vesical &
vertebral venous plexuses
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Blood & Lymph, continued
3. Lymphatics
a. Most terminate in internal iliac &sacral nodes (unable to palpate)
b. From posterior: to external iliac
nodes (unable to palpate)
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Detailed Anatomy, contined
H. Glandular tissue
1. 30 - 50 different glandular elements
a. Serous glands
b. 20 - 30 ducts empty into prostaticurethra
2. Most are posterior & lateral to urethra
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Blood & Lymph, continued
3. Prostatic secretionsa. Thin, milky, alkaline (looks like
skim milk)
b. Discharged at ejaculation
c. Make up ~ 1/3 of semen
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Detailed Anatomy, continued
I. Prostate size changes
1. Small at birth2. Enlarges at puberty
3. Maximum at about 13
4. Progressive enlargement after 40
5. Sometimes: undergoes atrophy
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III. Pathology
A. Benign
prostatichypertrophy
(BPH):
1. Affects ~90%
of men >50
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BPH, continued
2. Common cause of urethral obstruction:
causes
a. Nocturiab. Dysuria
c. Urgency
d. Back-pressure effects
e. Complete obstruction can occur
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Pathology, continued
B. Prostate cancer1. Most common
cancer in males
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Pathology, continued
2. Metastasizes via blood (hematogenous)
or lymph (lymphogenous)3. Common sites: vertebrae, pelvis
a. Via venous plexus surrounding
prostateb. Bone or direct metastasis most
common
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Prostate Cancer: Routes of Metastasis
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Pathology, continued
C. Prostatitis (accompanied by cystitis)
1. Inflammation of gland
2. Gland enlarges, becomes tender
3. Causes: gonorrhea? Other UTIs?
STDs?
4. May require antibiotics, massage5. Symptoms: chills, painful urination,
back pain
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Pathology, continued
A. Prostatic concretions (aka: corporaamylacea [starch bodies])
1. Small spherical or ellipsoid bodies
2. Number increases with age
3. May become calcified as male ages4. May simulate carcinoma
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Digital Rectal Exam
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Pathology, continued
E. Rarely, prostatic abscesses develop1. Frequently caused by gonorrhea2. May rupture through to rectum, bladder,
perineum
3. Other causes:a. Urethritis
b. Epididymitis