This document provides an overview of radiological imaging of scrotal diseases. It begins with the anatomy of the scrotum and its layers. It then discusses congenital diseases like cryptorchidism, which is the absence of one or both testes from the scrotum. Cryptorchidism can occur if the testes fail to descend from the abdomen into the scrotum. The document presents various imaging examples of cryptorchidism showing undescended testes in the inguinal canal or abdomen. It also discusses inflammatory diseases, trauma, testicular torsion, masses, and other pathologies that can be imaged and evaluated radiologically.
4. Anatomy of the Scrotum
Anatomic structures include:
Testis
Epididymis
Vas deferens
Venous plexus
Testicular artery
Appendix of epididymis (remnant from
embryogenesis)
Appendix of testis (remnant from
embryogenesis)
5. Anatomy of the Scrotum:
Layers include(Testis: Seminiferous
tubules)
Tunica albuginea
Visceral layer of Tunica vaginalis
Parietal layer of Tunica vaginalis
Fascia
Dartos muscle
Skin
6.
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9. Cryptorchidism (derived from the Greek kryptos, meaning hidden, orchis,
meaning testicle) is the absence of one or both testes from the scrotum. It is a
common birth defect regarding male genitalia. In unique cases,
cryptorchidism can develop later in life, often as late as young adulthood.
About 3% of full-term and 30% of premature infant boys are born with at least
one undescended testis. However, about 80% of cryptorchid testes descend by
the first year of life (the majority within three months), making the true
incidence of cryptorchidism around 1% overall. Cryptorchidism is distinct from
monorchismm, the condition of having only one testicle.
A testis absent from the normal scrotal position can be:
found anywhere along the "path of descent" from high in the posterior
(retroperitoneal) abdomen, just below the kidney, to the inguinal ring; found
in the inguinal canal; ectopic, that is, found to have "wandered" from that
path, usually outside the inguinal canal and sometimes even under the skin of
the thigh, the perineumm, the opposite scrotum, or the femoral canal;
found to be undeveloped (hypoplastic) or severely abnormal (dysgenetic);
found to have vanished (also see anorchia).
Congenital anomalies of the testis.
10. About two thirds of cases without other abnormalities are
unilateral; one third involve both testes. In 90% of cases an
undescended testis can be felt in the inguinal canal; in a minority the
testis or testes are in the abdomen or nonexistent (truly "hidden").
Undescended testes are associated with reduced fertility, increased
risk of testicular germ cell tumors and psychological problems when
the boy is grown. Undescended testes are also more susceptible to
testicular torsion and infarction and inguinal hernias. "Usually the
testicle will descend into the scrotum without any intervention
during the first year of life, but to reduce these risks, undescended
testes can be brought into the scrotum in infancy by a surgical
procedure called an orchiopexy.
Although cryptorchidism nearly always refers to congenital absence
or maldescent, a testis observed in the scrotum in early infancy can
occasionally "reascend" (move back up) into the inguinal canal. A
testis which can readily move or be moved between the scrotum and
canal is referred to as retractile.
107. Liposarcoma. Axial T1-weighted fat-supressed and contrast-enhanced image
shows enhancement of the solid non-fatty components of the tumor.
108. Liposarcoma. Coronal T2-weighted (a), axial T2-weighted (b), axial
T1-weighted (c) and T2-weighted fat-supressed images show right
inguino-scrotal mass with heterogeneous signal intensity.
109. Axial contrast-enhanced CT image shows bilateral inguinal
cystic metastases of epidermoid carcinoma of the penis.