Anatomy Of Male Genital System Flashcards
The primary male sex organs
Testis
The………….. testis hanging lower down than the ……………… .
Left , Right
Surface anatomy of the testis :
It has;
▪ Two poles (upper and lower).
▪ Two borders (anterior and posterior).
▪ Two surfaces (medial and lateral).
Site of testis :
Suspended by the spermatic cord in the scrotum.
The upper pole of the testis:
1) It is covered by the head of the epididymis.
2) It has attachment to the spermatic cord
Anterior border of the testis :
convex, smooth & fully covered by the tunica vaginalis
The posterior border of the testis
It is closely related to the body & tail of the epididymis AND the ductus deferens ( vas deferens) partially covered by the tunica vaginalis
To differentiate the lateral surface from the medial surface of the testis :
By the sinus of epididymis, at lateral aspect.
Course of testis location :
1) Testes develop on the posterior abdominal wall
2) Before birth and through the inguinal canal , they descend to reach the
scrotum, carrying their blood vessels, lymphatics,nerves&process of peritoneum (Processus vaginalis).
Coverings (coats) of the testis :
1) Tunica vaginalis
2)The tunica albuginea
3) The tunica vasculosa
Layers of tunica vaginalis :
a. Inner visceral layer.
b. Outer parietal layer.
c.A tunical space: contains thin film of serous fluid is normally present in between the two layer.
Define tunica vaginalis :
It is a closed sac of peritoneum encloses the testis; it covers the whole testis except its posterior border
At the time of birth, the proximal part of processus vaginalis at the deep inguinal ring is obliterated to form VESTIGUE of processus vaginalis
Define tunica Albuginea :
It is a dense, white fibrous coat covering the testis all around, it is covered by the visceral layer of tunica vaginalis, except posteriorly where the testicular vessels and nerves enter the gland.
It is thickened along the posterior border of the testis to form Mediastinum testis .
About the mediastinum testes :
It sends septa, dividing the testis into compartments (about 200-300).
▪ Each compartment contains 2 thin highly convoluted tubules callednseminiferous tubules,
▪ seminiferous tubules unite into a straight seminiferous tubules at the mediastinum
▪ straight seminiferous ductules unite to form a network of canaliculi termed the rete testis.
▪ The upper part of the rete testis gives rise to 12 to 20 efferent ductules (vasa efferentia) which form the greater part of the head of epididymis.
▪ efferent ductules (vasa efferentia) unite together to form the duct of the epididymis.
Parts of the epididymis:
It is represented in 3 parts:
1 ) Head of the epididymis
2 ) Body of the epididymis
3 ) Tail of the epididymis
About the head of the epididymis :
It is formed by the dilated ends of the efferent ductules which unite to form a single coiled duct overlying the upper pole of the testis.
About the body of the epididymis :
It is the middle part of the epididymis.
About the tail of the epididymis :
It is the lower part of the epididymis. It is continuous with the ductus deferens at the inferior pole of the testis.
Arterial supply of the testis
Testicular artery
Arterial supply of the epididymis
Artery of the vas deferens.
Venous drainage of testis and epididymis :
through the pampiniform plexus of veins to the testicular vein that ends in the inferior vena cava on the right side AND in the left renal vein on the left side
Lymphatic drainage of testis and epididymis :
Para-aortic lymph nodes
Testicular tumor spread to the para aortic lymph nodes
Varicocele
Enlargement of the pampiniform plexus due to pressure by the sigmoid colon on the left testicular vein which in turn drains into the left renal vein THEN it is more commonly seen in the left side
Define The spermatic cord :
group of structures that partly lie in the inguinal canal & partly in the scrotum
The spermatic cord begins in ………………………….. and ends at ……………………………….
Deep inguinal ring // testis
Constituents of the spermatic cord :
3-Vs. 3-arteries. 2- Nerves. 1-lymphatic
1)Vas deferens
2)Vestige of the processus vaginalis
3) Pampiniform plexus of Veins (testicular veins)
4) Artery of vas deferens from inferior vesical artery
5) Testicular Artery from abdominal aorta
6) Cremasteric Artery from inferior epigastric
7) Genital branch of the genitofemoral nerve
8) Sympathetic plexus of nerves around arteries
9) Lymphatics from testis &epididymis
Covering of the spermatic cord
1) External spermatic fascia
2) Cremasteric fascia
3) Internal spermatic fascia
External spermatic fascia of the spermatic cord is derived from
Aponeurosis of external oblique muscle
Cremasteric fascia of the spermatic cord is derived from :
the internal oblique muscle
Internal spermatic fascia of spermatic cord is derived from
transversalis fascia
Cremasteric muscle and fascia are supplied ( nerve ) :
genital branch of genitofemoral nerve L1,2
Action of Cremasteric muscle :
contraction ; it elevates the testis close to the body
What is Cremasteric reflex :
Gentle stroke on medial side of thigh➔ contraction of cremasteric muscle➔ elevation of testis
Define the scrotum :
It is a skin bag containing the testis, epididymis and lower part of the spermatic cord.
What divides the scrotum is :
a median raphe
The scrotum is divided into :
1) Superficial fascia of scrotum
2) Deep membranous layer ( Colle’s fascia )
About superficial fascia of the scrotum :
Contains no fat (to help reduce temperature around testis ➔ normal spermatogenesis)
Superficial fascia is replaced by the Dartos Muscle which is an involuntary smooth muscle supplied by sympathetic fibers.
About Deep membranous layer ( Colle’s fascia ):
is continuous with deep membranous layer of anterior abdominal wall (Scarpa’s fascia )
Sensory Nerve supply of the scrotum
(to the skin):
Anterior : L1(ilioinguinL)
Posterior: S3&4(pudendal)
Motor Nerve supply of the scrotum
(to Dartos M):
Sympathetic fibers through the genital branch of the genitofemoral nerve
Spinal anethesia and the scrotum :
scrotum requires many spinal nerves to be blocked
Parts of penis :
The penis has a root and a free body.
About the root of the penis :
It is the attached portion OR proximal portion OR fixed portion
It consists of:
The two crura; which are the proximal parts of the corpora cavernosa.
The bulb of the penis: which is the proximal expanded part of the corpus spongiosum.
Define the body of the penis :
It is entirely covered by skin & fascia around the free parts of the corpora cavernosa& corpus spongiosum.
About the glans penis :
It is the head of penis which is formed from the expansion of corpus spongiosum over the two distal ends of the corpora cavernousa
About the corona of the glans :
raised circular margin at the base of the glans
About the neck of the glans :
The depression posterior to the corona
Ligaments of penis:
1-The suspensory ligament of the penis; It is attached to the symphysis pubis.
2-Fundiform ligament of the penis; It is attached to linea alba.
Arterial supply of the penis :
internal pudendal artery
Venous drainage of the penis:
1) Superficial dorsal vein
2) Deep dorsal vein
Course of vas deferens
Beginning: in the scrotum as a continuation of the tail of epididymis.
Course ; ascends in the spermatic cord and traverses the inguinal canal
Termination: by forming a dilatation called the ampulla of vas medial to the seminal vesicle on the posterior surface of the urinary bladder, where it joins the duct of the seminal vesicle forming the ejaculatory duct which opens in the prostatic urethra.
Vasectomy definition :
Vasectomy is surgical division of the vas deferens.
Vasectomy prevents sperms from being released into semen during ejaculation, thus preventing pregnancy.
“permanent male sterilization”
Define the ejaculatory duct :
Each is formed by the union of the vas deferens and the duct of the seminal vesicle and It opens on the prostatic urethra
Shape and Site of seminal vesicle:
Each seminal vesicle is a coiled tube about 5cm long.
It has a blind upper end. However , Its other end joins the lower end of the vas to form the ejaculatory duct.
It lies on the base of urinary bladder, below the termination of the ureter and lateral to ampulla of vas deferens.
Site of prostate gland
It lies immediately inferior to the bladder,
posterior to the symphysis pubis and anterior to
the rectum.
Shape of prostate gland :
It has a base (upward), an apex (downward) and
four surfaces; anterior, posterior and two
inferolateral surfaces.
Size of prostate gland :
It measures 3 cm in its vertical diameter, 4 cm in its
transverse diameter at the base.
Base of the prostate: relations :
It is directed upwards. It is pierced by the urethra.
Apex of the prostate relation
It is directed downwards.
Anterior surface: relations
Its upper part is connected to the pubic bones by the puboprostatic ligaments.
▪ The urethra emerges from this surface anterosuperior to apex of the gland.
Posterior surface: relations
It is pierced by the two ejaculatory ducts at its upper border.
▪ This surface can be felt by P/R examination
Inferolateral surfaces relations :
One on each side they are related to (levator prostate) muscle.
Structures inside the prostate:
Prostatic urethra.
2 Two ejaculatory ducts:
▪ One on each side of the median lobe of prostate.
3- Prostatic utricle:
▪ It is a blind sac extending upwards into the substance
of the median lobe of the prostate.
Prostate gland lobes
Anterior lobe (isthmus):
It is infront of the prostatic urethra, connecting the two
lateral lobes
Posterior lobe
It is behind the prostatic urethra and below the ejaculatory
ducts.
Median lobe:
It is behind the prostatic urethra & between the two
ejaculatory ducts.
uvula vesicae
It projects slightly upwards into the cavity of the bladder just
behind the internal urethral orifice
Two lateral lobes
They form the main bulk of the gland.
▪ They are on either side of the prostatic urethra
Blood supply
of prostate:
Arteries;
▪
Inferior vesical, middle rectal.
Veins :
The veins form a plexus around prostate.
▪ It drains through the vesical veins into the internal
iliac vein.
About prostatic veins
The prostatic venous plexus is
connected to the internal vertebral venous plexus by
valveless veins. This fact explains the reason why
cancer prostate commonly metastases to the vertebral bodies
Bulbourethral Glands or Cowper’s
Are two pea-size glands that lie
posterolateral to membranous part of
urethra, largely embedded within
external urethral sphincter.
⚫ Their ducts pierce perineal membrane
and open on posterior wall of penile
urethra in bulb of penis
