Inguinal canal lipomas, also known as spermatic cord or round ligament lipomas, are a relatively common but often under-recognized finding on imaging.
Lipomas are usually asymptomatic but can sometimes cause pain and discomfort. They can present as a mass lesion.
They have no communication with the peritoneal fat. They are not considered as true tumors of fat but as extrusions of extraperitoneal fat extending into the inguinal canal.
It is seen as a well defined, solid hyperechoic mass lesion, expanding the inguinal canal and gently effaces the spermatic cord.
The lesion shows attenuation corresponding to fat (-20 to -70 HU). No associated soft tissue component or enhancement.
Oval shaped lesion with typical fat signal characteristics:
- T1: high signal
- T2: high signal
- fat-suppressed sequences: shows fat suppression
Treatment and prognosis
They are a benign entity and no treatment is usually required in incidental asymptomatic cases. Resection can be offered to patients who are clinically symptomatic.
On imaging, possible differential considerations include:
- inguinal hernias containing fat
- other inguinal canal / spermatic cord masses 3
- subcutaneous lipoma overlying the spermatic cord
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