Diagnostic Ultrasound - Abdomen and Pelvis

Focal Extratesticular Mass
– 3-50 mm
– Most common in men over 20 years old
– Usually unilateral, more common on left side
○ Variable US appearance
– Typically seen as well-circumscribed, round to oval,
homogeneous mass, variable echogenicity
• Inguinal Hernia
○ Herniation of abdominal contents into scrotum
○ Accentuated by Valsalva maneuver, real-time evaluation
essential
○ Solid, irreducible mass if obstruction/strangulation
○ Ill-defined echogenic structure representing mesentery ±
bowel in herniated sac
– Obstruction at neck of hernia sac leads to
strangulation of herniated contents
• Encysted Hydrocele of Cord
○ Patent processus vaginalis seen in infants; associated
ascites may also be seen
○ Elongated fluid collection within layers of spermatic cord
located above level of testis and epididymis
• Papillary Cystadenoma
○ On US, variable appearance
– Large, solid tumors, echogenic, ± cystic spaces
○ Typically 1-4 cm
○ Identified in men with von Hippel-Lindau disease (50-
70%)
• Lipoma
○ Among most common extratesticular neoplasms
○ Usually involves spermatic cord
○ Homogeneous, well-circumscribed, variable-sized,
hyperechoic, solid mass
• Epididymal/Scrotal Wall Abscess
○ Abscess involving epididymis or scrotal wall as
complication of severe epididymoorchitis
• Fibrous Pseudotumor
○ Reactive fibrous proliferation in epididymis
– Tunica albuginea may be another site for such fibrous
proliferation
– Lesions may be as large as 8 cm
○ Generally hypoechoic ± posterior acoustic shadowing
• Leiomyoma
○ 2nd most common epididymal neoplasm
○ Slow growing, hence delayed presentation (generally 5th
decade)
○ Solid or cystic, variable US appearance, ± calcifications
Helpful Clues for Rare Diagnoses
• Liposarcoma of Spermatic Cord
○ Aggressive fat-containing malignancy derived from
mesenchymal tissue
○ Present as painless inguinal mass which may be mistaken
for inguinal hernia
• Sclerosing Lipogranuloma
○ Rare, hypoechoic paratesticular mass, histopathological
correlation
• Metastases
○ 25% of solid tumors of epididymis are malignant;
majority of these are metastases
○ On ultrasound, most metastatic lesions are hypoechoic,
but no other specific feature differentiates them from
other epididymal neoplasms
• Funiculitis
○ Inflammation of the entire spermatic cord
○ Presents with pain and swelling
○ Hypoechoic soft tissue around vas deferens extending
into inguinal canal
• Vasitis
○ Inflammation of only vas deferens
SELECTED REFERENCES
1. Annam A et al: Extratesticular masses in children: taking ultrasound beyond
paratesticular rhabdomyosarcoma. Pediatr Radiol. ePub, 2015
2. Inokuchi R et al: Noninfectious Funiculitis. J Emerg Med. ePub, 2015
3. Mirochnik B et al: Ultrasound evaluation of scrotal pathology. Radiol Clin
North Am. 50(2):317-32, vi, 2012
4. Philips S et al: Benign non-cystic scrotal tumors and pseudotumors. Acta
Radiol. 53(1):102-11, 2012
5. Wasnik AP et al: Scrotal pearls and pitfalls: ultrasound findings of benign
scrotal lesions. Ultrasound Q. 28(4):281-91, 2012
6. Cassidy FH et al: MR imaging of scrotal tumors and pseudotumors.
Radiographics. 30(3):665-83, 2010
Differential Diagnoses: Scrotum
Epididymitis
Epididymitis
(Left) Longitudinal ultrasound
shows a markedly enlarged,
predominantly hypoechoic
head of the epididymis ſt,
features suggestive of acute
epididymitis. Note the
preserved size, echo pattern of
testis st, and moderate
reactive hydrocele . (Right)
Transverse color Doppler
ultrasound in another patient
shows marked increase in
intrinsic vascularity st of an
inflamed epididymis. Note the
undistorted pattern of the
vessels, which helps to
differentiate diffuse
inflammation from a
neoplasm.
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