Orbital cavernous hemangioma
Orbital cavernous hemangioma cavernous hemangiomas (OCHs) are low-flow, angiographically occult vascular malformations that are often considered at the cusp of orbital vascular tumors and orbital vascular malformations 1).
They are distinctly classified as low-flow AVMs in the spectrum of orbital vascular malformations, such as venous malformations, venolymphatic malformations, high-flow AVMs, carotid-cavernous fistula, and aneurysms. Typically well-circumscribed and slow growing, the pathology represents 4-5% of all orbital tumors 2) 3).
They are the most common intraorbital primary orbital tumors and the most common orbital vascular lesions in adults 4) 5).
OCHs are marked by blood-filled endothelial-lined caverns, which sets them apart from other vascular orbital tumors, such as capillary hemangiomas, hemangiopericytomas, hemangioendotheliomas, and angiofibromas 6).
OCHs lack malignant potential and capacity for endothelial capillary proliferation as seen in pediatric orbital capillary hemangiomas 7).
They are often asymptomatic, but may present with visual symptoms, such as painless ptosis and visual field deficits secondary to compression of the optic nerve. Given the potential of permanent optic nerve dysfunction, current evidence suggests such lesions should be resected as early as possible after diagnosis when patients are symptomatic 8).
Surgical approach is dictated by the location of the lesion within the retroconal space, and possible options may include a lateral zygomatic–frontal orbitotomy (modified Kronlein procedure), transcranial (orbitocranial) approach, or a transconjunctival approach 9)
There have been a number of studies comparing the nature of OCHs with cerebral cavernous malformations (CCMs) in terms of pathology and clinical behavior. Hejazi et al. have written extensively about the two lesions and conclude that they are clinically, histopathologically, and neuroradiologically different 10) 11) 12).