Diagnostic Ultrasound - Abdomen and Pelvis

Undescended Testis
Diagnoses: Scrotum
TERMINOLOGY
• Cryptorchidism, cryptorchism
• Definition: Incomplete descent of testis into base of
scrotum
IMAGING
• Unilateral or bilateral absence of testis in scrotum
• Located anywhere from kidney to inguinal canal, inguinal
canal most common (80%)
○ Bilateral in 10%
• Ultrasound features: Ovoid homogeneous, hypoechoic,
well-circumscribed structure smaller than normal
descended testis
• MR: Useful for detecting intraabdominal testis, if not seen
by ultrasound
TOP DIFFERENTIAL DIAGNOSES
• Inguinal lymphadenopathy
• Inguinal hernia
KEY FACTS
• Anorchia: Absent testis
PATHOLOGY
• Undescended testis: Arrest of testis along its normal path
of descent
• Ectopic testis: Testis located outside its normal path of
descent
CLINICAL ISSUES
• Complications
○ Incidence of testicular cancer: 1:1,000-1:2,500
○ Torsion
○ Atrophy/infertility
○ Trauma
• Treatment
○ Orchiopexy before age 2 to preserve fertility
○ Orchiectomy: Consider in patients aged 12-50 years
(Left) Graphic shows a testis
ſt at a high scrotal location
due to incomplete descent. An
undescended testis may be
located anywhere from the
kidney to the inguinal canal.
(Right) Grayscale ultrasound
demonstrates an undescended
testis with numerous (> 5 per
field) punctate, nonshadowing
hyperechoic foci , consistent
with microlithiasis. Testicular
microlithiasis in a cryptorchid
testis is associated with
increased risk of development
of testicular carcinoma. This
testis will need routine followup.
(Left) Spectral Doppler of a
cryptorchid testis
demonstrates a hypoechoic
intratesticular mass with
internal blood flow
pathologically confirmed to be
a seminoma. (Right) Color
Doppler shows a cryptorchid
testis. The heterogenous
echogenicity and lack of color
flow within this testis is
consistent with testicular
torsion.
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