Cholesterol granuloma of the orbit

Abstract

Purpose: The aim of this study was to present image findings, clinical and histopathologic features, and surgical management of orbital cholesterol granuloma (CG), a rare orbital entity.

Methods: Findings from 2 patients with orbitofrontal CG are presented along with a review of the literature on CG of the orbit.

Results: Both patients were 40-year-old men. The common symptoms of this condition in the present cases were proptosis and inferomedial displacement of the globe. Computed tomography scan in patient 1 revealed the presence of a cystic lesion without bone erosion in the superolateral orbital roof. Magnetic resonance imaging in patient 2 revealed a non-contrast-enhancing lesion with moderate signal intensity on T1-weighted images and high signal intensity on T2-weighted images. For both cases, anterior orbitotomy through subbrow incision by drainage and curettage resulted in a curative outcome. No lesion recurrence was observed by 5 years after surgery in 1 case and 3 years in the other. Histopathologic evaluation revealed numerous inflammatory cells, blood degradation products, and cholesterol clefts. The absence of epithelial elements led to the diagnosis of CG.

Conclusions: Orbital CG is a rare expansive cystic condition and nearly always occurs in the lateral region of the superior orbital ridge within the frontal diploic space. This condition shows a marked preponderance in middle-aged males. The findings that computed tomography scan did not reveal bone erosion in patient 1, and magnetic resonance imaging examination showed moderate signal intensity, rather than high signal intensity, on T1-weighted images in patient 2 indicated that these represented unusual presentations. Surgical excision has a high success rate with a low incidence of recurrence.