WHAT ARE TESTES?
The testes are paired, ovoid organs responsible for the production of spermatozoa and testosterone.
Normal spermatogenesis occurs only at a temperature lower than that of
the abdominal cavity, hence the descent of the testes into the scrotum(outpouching of the lower part of the
anterior abdominal wall)
The tunica albuginea(the fibrous envelope that extends the length of the corpora cavernosa penis|
and corpus spongiosum penis) is the outer, fibrous capsule of the testis.
1. The testes are surrounded incompletely (medially, laterally, and anteriorly, but not posteriorly) by
a sac of peritoneum called the tunica vaginalis(the pouch of serous membrane that covers the testes).
2. Beneath the tunica vaginalis, the testes are surrounded by a thick connective tissue capsule called
the tunica albuginea because of its whitish color.
3. Beneath the tunica albuginea, the testes are surrounded by a highly vascular layer of connective
tissue called the tunica vasculosa.
4. The tunica albuginea projects connective tissue septa inward toward the mediastinum, which
divides the testes into about 250 lobules, each of which contains one to four highly coiled seminiferous
tubules. These septa converge toward the midline on the posterior surface, where they meet to form a
ridge-like thickening called the mediastinum.
5. The testes contain the seminiferous tubules, straight tubules, rete testes, efferent ductules,
and the Leydig (interstitial) cells.
B. Arterial Supply Of Testes
1. The arterial blood supply of the testes is from the testicular arteries, which arise from the abdominal
aorta just inferior to the renal arteries.
2. There is a rich collateral arterial blood supply from the internal iliac artery via the artery of the
ductus deferens, inferior epigastric artery via the cremasteric artery, and femoral artery via the
external pudendal artery. The collateral circulation is sufficient to allow ligation of the testicular
artery during surgery.
C. Venous Drainage of testes
1. The venous drainage of the testes is to the right testicular vein (which empties into the inferior
vena cava [IVC]) and the left testicular vein (which empties into the left renal vein).
2. This is important in males, where the appearance of a left-side testicular varicocele may indicate
occlusion of the left testicular vein and/or left renal vein due to a malignant tumor of the kidney.
3. The testicular veins are formed by the union of the veins of the pampiniform plexus.
D. Lymphatic Drainage of testes
The lymph drainage of the testes is to the lateral aortic nodes.
Clinical Considerations of testes
1.What is Cryptorchidism ?
Cryptorchidism is a condition in which one or both of the testes fail to descend from the abdomen into
the scrotum. occurs when the testes begin to descend along the normal pathway but
fail to reach the scrotum (versus an ectopic testes, which descends along an abnormal pathway).
Undescended testis or cryptorchidism: The organ may lie in the lumbar, iliac, inguinal, or upper scrotal
region.
The undescended testis is generally found within the inguinal canal or abdominal cavity near the deep
inguinal ring. Bilateral cryptorchidism results in sterility since the cooler temperature of the scrotal sac
is necessary for spermatogenesis. Cryptorchidism is associated with an increased incidence of cancer
and torsion.
The important features of an undescended testis are as follows.
(a) The testis may complete its descent after birth.
(b) Spermatogenesis may fail to occur in it.
(c) A malignant tumour is more prone to develop in it.
(d) The condition can be surgically corrected.
2.WHAT IS HYDROCELE OF TESTES?
Hydrocoele is a condition in which fluid accumulates in the processus vaginalis.
Hydrocele of Testes occurs when a small patency of the processus vaginalis remains so
that peritoneal fluid can flow into the tunica vaginalis surrounding the testes. The photograph shows a
bilateral hydrocele.
The various types of hydrocoele are as follows :
(a) Vaginal, in tunica vaginalis.
(b) Infantile, when the processus vaginalis is closed at the deep inguinal ring.
(c) Congenital, when the entire processus vaginalis is patent and communicates with the peritoneal
cavity.
(d) Encysted, when the middle part of the processus is patent.
3.WHAT IS TORSION OF TESTES?
Torsion is the rotation of the testes about the spermatic cord, usually toward the penis
(i.e., medial rotation). An increased incidence occurs in men with testes in a horizontal position and a
high attachment of the tunica vaginalis to the spermatic cord (“bell clapper deformity”). Torsion is a
medical emergency since compression of the testicular vessels results in ischemic necrosis within 6
hours.
The photograph shows the cut section of the testis from a man
who experienced sudden excruciating scrotal pain. Note the diffuse hemorrhage and necrosis of the
testis and adnexal structures.
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