Normal Anatomy Flashcards
the scrotum contains
the testes and parts of the spermatic cord
the testes are the
site of the sperm production
testes form the essential
component of the male reproductive system
sperm leaves the
testes via the epididymis
sperm then drains into the
ductus deferens (vas deferens)
vas deferens
thick-walled tube in the male reproductive system that transports sperm cells from the epididymis, where the sperm are stored prior to ejaculation
the epididymis and lower portions of the ductus deferens are located
within the scrotum
the ductus deferens is joined by
blood vessels supplying the testes, creating the contents of spermatic cord
testis are paired
symmetric
what resides in the scrotum
7 oval-shaped glands
the function of the testis is to
- produce sperm
- produce and discharge hormones, primarily testosterone
adults testis measures
3-5x2-4x3 cm
the testicle is surrounded by a
fibrous capsule, tunica albuginea-inner
the tunica albuginea is covered by
the tunica vaginalis- outer
tunica vaginalis
is a saccular extension of the peritoneum into the scrotal chambers
the inner or visceral layer of the tunic vaginalis covers
the testis and epididymis
the outer or parietal layers of the tunica vaginalis lines
the scrotal chamber
parietal layer
outermost (followed by skin)
visceral layer
innermost, contiguous with testis
cavity of the tunica vaginalis
space between the two layers which normally contains a very small amount of serous fluid for lubrication during movement
tunica albuginea
a dense fibrous capsule surrounding the testicle
tunica albuginea seen sonographically
as an echogenic line on ultrasound
appendix testis
a remnant of the Mullerian duct , a small ovoid structure located beneath the head of the epididymis
appendix epididymis
small protuberance from the epididymal head easily mistaken for pathology
from inner to outer
- seminiferous tubules
- rete testis
- efferent ductules
- ductus epididymis
- vas deferens
function of the vas deferens
transports sperm from the epididymis to the prostate to be expelled via the urethra
the rete testis
is an anastomosing network of delicate tubules located in the hilum of the testicle that carries sperm to the epididymis
the efferent ductules carry
the seminal fluid from the rete testis to the epididymis
the epididymis is composed
of a head, body and tail
epididymis is position
parallel to the testicle
the epi head is located
adjacent to the superior pole of the testis
the epi tail courses
cephalad as does the vas deferens
normal epididymis sonographically
- isoechoic or hypoechoic compared with testis
- echo texture coarser
normal epididymis measures
6 to 7 cm tubular structure beginning superiorly and then coursing posrerolaterally to testis
epididymis head is the
largest part, 6 to 15 mm in width
body of the epididymis
smaller than head
body of the epididymis follows
posterolateral aspect of testis from upper to lower pole
tail of the epididymis
slightly larger and positioned posterior to lower pole of testis
appendix of the epididymis
small protuberance from head of epididymis
spermatic cord
it runs from the abdomen to the testicle in the scrotum
spermatic cord consists of the following
- vas deferens
- cremasteric, differential, testicular arteries
- pampiniform plexus of veins
- lymphatics
- nerves
tunica vaginalis
Multi-layered membrane lining the inner wall of the scrotum and is continuous with the abdominal peritoneum, best delineated on USD in the presence of pathology
dartos muscle
is a layer of muscle fibers lying beneath the scrotal skin and dividing the scrotum into 2 chambers
scrotal raphe
the division of the two scrotal chambers (cleavage)
scrotal pearl is aka
scrotolith
seminiferous tubules
are the specific site of sperm production
seminiferous tubules aka
spermatogenesis
the septula forms wedge shaped
compartments that contain the seminiferous tubules
scrotal pearls is
incidental and appears on the extra testicular surface
scrotal pearls are like
macro calcifications inside the scrotum
scrotal pearls cover the space of
tunica vaginalis (serosal covering of testes) or sinus of the epididymis
scrotal pearls have no
clinical significance
scrotal pearls sonographically
echogenic focus with shadowing
mediastinum testis
posterior aspect of tunica albuginea reflects into testis to form vertical septum
mediastinum sonographically
seen as a linear echogenic line
the rete testis
a series of interconnected channels within the mediastinum testis and is not routinely visible on ultrasound unless ectatic
what is the primary source of blood flow to the testis
testicular arteries
the testicular arteries descend
in the retroperitoneum and enter the spermatic cord in the deep inguinal ring
testicular arteries course along the
posterior surface of each testis and pierce the tunica albuginea, forming the capsular arteries, which branch over the surface of the testis
the capsular arteries give rise
to centripetal arteries, which course from the testicular surface toward the mediastinum along the septa
before reaching the mediastinum, they back curve backward, forming
the recurrent rami (centrifugal arteries)
testicular blood flow is supplied by the
- differential artery
- cremasteric artery
- testicular artery
the testicular artery divides into
capsular and centripetal (intratesticular) branches
the blood flow in the transmediastinal artery courses from the
mediastinum to the testicular capsule
cremasteric artery
-mainly extratesticular structures, i.e.
- arise from a branch of the extension of iliac artery
