The central dot sign of epiploic appendagitis

摘要

Epiploic appendagitis is the acute inflammation and infarction of epiploic appendages, commonly secondary to torsion. It is a great mimicker as its clinical manifestation may be similar to appendicitis, diverticulitis, or colitis. Focal abdominal pain, tenderness, and mild pyrexia are clinical features of the condition [1]. Epiploic appendages are pedunculated adipose structures which extend from the serosal surface of the colon, along the free taenia and taenia omentalis. They are abundant in the caecum and sigmoid colon and absent in the rectum [2]. CT is the usual modality for diagnosis and features include: ? Ovoid mass with central fat density and peri-lesional inflammatory change adjacent to the colonic wall. ? "Central dot sign"-central high density dot in the lesion representing a thrombosed vessel, also known as the "dense central vessel sign" (Fig. 1) [3]. ? "Hyperattenuating/hyperdense ring sign"-a hyper-dense enhancing rim surrounding the lesion [4]. ? Extension of the inflammatory changes to involve the local peritoneal surfaces is possible. ? Calcification within the infarcted lesion may occur over time.