Cavernous malformations of the orbit: a distinct entity? A review of own experiences.

We collected data to provide evidence that orbital cavernous malformations (CMs) are histopathologically, neuroradiologically, and clinically different from cerebral CMs and may represent a distinct entity. In this study, the main clinical, histopathological and radiological characteristics of 19 patients (11 females and eight males, mean age 49.1 years) with orbital CMs out of a series of 376 orbital tumors are analyzed and compared with 107 cases with cerebral CMs treated in the same period. Decrease of visual acuity and painless progressive proptosis were the main clinical signs observed in 17 patients (89%). Complete microsurgical excision of lesions via individualized approaches was obtained in all cases. Follow-up examinations were obtained after a mean of 3.1 years (11 months to 7 years) and yielded complete recovery in 14 patients, while five remained clinically unchanged. Based on clinicopathological and neuroradiological studies of these 19 patients with orbital and 107 patients with cerebral CMs treated in the same period, we found evidence that orbital CMs have specific features to distinguish them from cerebral CMs. Orbital CMs, in contrast to the cerebral CMs, showed non-degenerated well-developed vessel walls and were covered by a hard and compact capsule. Clinical symptoms are characterized by the growth of orbital CMs due to intraluminal thrombosis and subsequent recanalization of cavernous vessels; there were no signs of hemorrhage. We found evidence to suggest that orbital CMs represent a distinct clinicopathologic and neuroradiologic entity.