CT of inguinal canal lipomas and fat-containing inguinal hernias

Abstract

Inguinal canal lipomas are a frequent, often unrecognised finding on abdominopelvic CT. Commonly referred to as spermatic cord or round ligament lipomas, they are not true tumours of fat but are extrusions of extraperitoneal fat into the inguinal canal. Their fat content and shared location in the inguinal canal result in confusion with fat-containing inguinal hernias with which they often coexist. As laparoscopic herniorrhaphies proliferate, greater awareness of the condition by radiologists is needed to provide accurate preoperative information. This pictorial essay highlights the differentiating diagnostic features of inguinal canal lipomas and fat-containing inguinal hernias.

The Case of Huge Pure Lipoma of the Spermatic Cord Misdiagnosed as Inguinal Hernia

“…On CT, especially below the level of the external inguinal ring, its fat content may be difficult to differentiate from mesenteric fat-containing inguinal hernia. However, it was known that spermatic cord lipoma could be discernable in coronal view, as it has a well demarcated superior wall with no opening to the peritoneum laterally to the inferior epigastric vessels, while the mesenteric fat accompanying hernias extend up either medially or laterally to the inferior epigastric vessels, toward the mesentery, without recognizable superior walls 5 . For the open approach, the inguinal incision is mandatory to observe whether there is peritoneal connection or not.…”

Hemorrhagic Complication of Protruding Preperitoneal Fat Presenting as an Incarcerated Inguinal Hernia in a Patient with Clinically Occult Inguinal Hernia

“…Computed tomography (CT) may differentiate inguinal canal lipoma from the fat-containing inguinal hernia by showing a well demarcated superior wall which can be traced back to their extra-peritoneal fat origin lateral to the inferior epigastric vessels in inguinal canal lipoma but no recognizable superior walls in hernia fats 6 . Recently Garvey 7 reported that lipoma of the spermatic cord was responsible for false-positive CT results when they used CT for the diagnosis of clinically occult groin hernia.…”

Usefulness of Computed Tomography for Differentiation of Primary Inguinal Hernia

“…A patient presenting with inguinal pain alone has also some diagnostic controversy which may necessitate surgical intervention. Therefore, accurate imaging is vital to ensure diagnosis of inguinal hernia in patients with such presentations (10,11). Scanner technology with multi-planar reformatting makes it possible to produce high resolution sagittal, coronal and oblique images in any plane from raw axial images that allows visualization of relevant anatomic structures (4,8,12,13).…”