111. Testes_Scrotum Flashcards
epididymus and associated ligaments
epididymus arises from mesonephric (Wolffian) ductepididymus attaches the efferent ducts of the testes to the vas deferensproper ligament of the testis—connects epididymus to testicleligament of the tail of the epididymus—connects epididymus/testicle to the vaginal tunic and spermatic fascia
what does the spermatic cord contain
—testicular artery—pampiniform plexus (venous system that thermoregulates)–ductus deferens and associated artery/vein–lymphatics–nervescremaster muscle is not part of the spermatic cord but travels onto the spermatic fascia and is made up of the internal abdominal oblique
blood supply to the testicle and ductus deferens
TESTICLE—testicular artery and vein (from aorta)—pampiniform plexus/testicular vein (right into cd vena cava and left into left renal vein)DUCTUS DEFERNS–ductus deferens artery (branch of prostatic which is a branch of internal iliac artery)
three layers of the scrotum
- skin2. tunica dartos (poorly developed smooth muscle mixed with elastic fibers and collagen)3. scrotal fasciafollowed by parietal and visceral vaginal tunicsdeep to visceral tunic is capsule to testicle = tunica albuginea
principle blood supply and innervation to scrotum
external pudendal arteryinnervated by superficial perineal nerve which is a branch of pudendal nerve
3 different cell types in the testicle
- Spermatogenic cells (spermatogonia–>spermotocytes–>spermatids motile, migrate to lumen of seminiferous tubules thru spermiation)2. Leydig interstitial cells (produce testosterone)3. Sertoli sustantacular cells (forms the blood testis barrier, support development and maturation of spermatozoa and control their release into the lumen; stimulated by FHS)
accessory sex glands in the dog versus cat
dog: prostatecats: prostate and bulbourethral glandsprostate fluid is alkaline which helps sperm survive in acid pH of female repro tract
thermoregulation of the scrotum
testes should have temp lower than body temp to prevent degeneration of seminiferous tubules/sperm1. pampiniform plexus2. cremaster muscle/tunica dartos3. thin skin with little SQ fat, sparse hair4. rich supply of sweat glands
cryptorchidism
testicular descent into the scrotum depends on the growth and action of the GUBERNACULUMddx is made until 6 months after birthunilateral (RIGHT) is more common than bilateral in dogs; bilateral are sterile bc thermal suppression of the testes but testosterone is still presentrisk neoplastic transformation (~10%), testicular torsion, urine spraying (cats) and concurrent congenital abN possibleconsidered heritable
palpation for location of cryptorchid testicle
palpation to locate the undescended testicle accurate 48% cats30% had incorrect initial surgical approaches
what test would help ddx bilateral cryptorchid from anorchid patient
testosterone stimulation testAb rads/ ultrasonographyexploratory surgery
testicular torsion
more often associated with intra-abdominal testicle bc more motile but can occur in the scrotumddx neoplasia, orchitis/epididymitisER–orchiectomy
most common testicular neoplasias
Primary testicular tumors:1. interstitial (Leydig) cell tumor—testosterone2. sustentacular (Sertoli) cell tumor–feminization3. seminomas4. metastatic adenocarcinoma–rare, look for GI neoplasia42% testicular tumors have more than one originslow/low rate of metsgood to excellent prognosis with orchiectomy
risk of testicular tumor when inguinal hernia is present
5x risk of testicular neoplasia when inguinal hernia is present
testicular tumors associated with inguinal cryptorchid testes
seminomas and sertoli cell tumors
