differences of sex development Flashcards
(14 cards)
covering of testis
Innermost layer - the internal spermatic fascia = transversalis fascia
Middle layer: cremaster muscle (skeletal muscle) and cremasteric fascia = continuation of the internal oblique muscle (it elevates the testes during sexual arousal and exposure to cold, exposure to warmth reverses the process)
Outermost layer - external spermatic fascia = external oblique
testes peritoneum
Deep to the internal spermatic fascia, the testis is covered by a closed sac of peritoneum, the tunica vaginalis (derived from the processus vaginalis) which has visceral and parietal layers between which is a film of peritoneal fluid.
Excess fluid in the tunica vaginalis can form a hydrocele.
descend of testes
It begins in the 10th week of pregnancy.
In the first or ‘transabdominal’ phase the testes enlarge as the mesonephric kidneys regress. Each testis is anchored at its upper pole to a cranial suspensory ligament and at its lower pole to the gubernaculum
- testosterone and INSL-3 and AMH control the descend of testes
inguinal canal - MALT
Upper wall: 2Muscles:· internal obliqueMuscle· transverse abdominusMuscle
Anterior wall: 2Aponeuroses:·Aponeurosis of external oblique·Aponeurosis of internal oblique
Lower wall: 2Ligaments:· inguinalLigament· lacunarLigament
Posterior wall: 2Ts:·Transversalis fascia· conjointTendon
tunica albuginea
dense white fibrous capsule which extends inwards forming septa that divide each testis into lobules that contain the SMT (where sperm are produced)
Sertoli cells
form the blood-testis barrier, support and protect spermatogenic cells, mediate the effects of T and FSH, and secrete inhibin which helps regulate sperm production by inhibiting secretion of FSH
In the spaces are Leydig cells which secrete T
spermatic cord
transmits important structures to and from the testis – vas deferens, arteries (3, testicular, ductus and cremaster), pampiniform plexus of up to 12 veins for cooling the blood supply, nerves (genital branch of the genitofemoral nerve), lymphatic vessels (cancer spread) and fibrous remnant of processus vaginalis.
cryptorchidism
Also known as ‘impalpable’ or ‘undescended’ testes
Bilateral vs unilateral
Majority of cases have no discernible aetiology – environmental factors have been implicated
Long term consequences on testicular function, including spermatogenesis, and risk of testicular cancer
Retained testis often smaller, suggesting prenatal testicular maldevelopment
Changes caused by the position itself can add further damage
More severe testicular dysgenesis = more severe cryptorchidism
orchidopexy
Any undescended testis after the age of 6 months should be referred for orchidopexy (treatment for descending the testes)
-orchidectemy- removal of testes
risk factors for cryptorchidism
Birthweight <2.5kg
Small for gestational age
Prematurity
Maternal diabetes, including gestational diabetes
Environmental factors may also play a role for the risk of cryptorchidism:
Organochlorines, phthalate monoesters, smoking have been linked to adverse effects in infant reproductive development
semen quality and cryptorchidism
Adult men with persistent bilateral cryptorchidism have azoospermia, whereas 28% after operation have normal sperm count
49% of men with persistent unilateral cryptorchidism have a normal sperm concentration as compared to 71% after orchidopexy
Earlier surgery (between 10 months and 4 years) preferable in bilateral cryptorchidism
complications of treatment for cryptorchidism
Immediate complications are haematoma, pain, wound infection
Long term complications are testicular atrophy, recurrent cryptorchidism
hypospadias
Most common congenital anomaly of the penis
1 in 300 births
Usually develops sporadically and without an obvious underlying cause
Ectopically positioned urethral meatus lies proximal to the normal site and on the ventral aspect of the penis, and in severe cases opens on to the scrotum
Chordee and hooded foreskin common
Associated with cryptorchidism and inguinal hernia
Frequency of associated anomalies increases with the severity of hypospadias
disorder of sex development
Any congenital condition in which development of chromosomal, gonadal or anatomic sex is atypical
