Purely endoscopic trans-nasal management of orbital intraconal cavernous haemangiomas: a systematic review of the literature.

The surgical management of medial and inferior orbital lesions is demanding via traditional external approach, since the conic-shaped surgical field is narrow and damage to neural, muscular or vascular structures of the orbit can have serious consequences. In recent years, the evolution of endoscopic endonasal approaches for lesions that goes beyond the nose brought the orbit to the attention of rhinosurgeons. If procedures such as transnasal orbital decompression and lacrimal pathways surgery have been described some decades ago, the last frontier of transnasal orbital surgery, namely intraconal tumor surgery, is a new and rapidly expanding field. Papers describing endoscopic endonasal approaches to the orbit appeared in the international literature, but most of them contain a small number of cases, also because the relatively rarity of intraorbital lesions. We herein report the results of a systematic review of the literature regarding the endoscopic endonasal approach to intraconal cavernous haemangiomas, the most common benign orbital lesion. The endoscopic management of intraconal cavernous haemangiomas results feasible and safe. A critical step of this kind of surgery is the management of the medial rectus muscle, mandatory to expose the intraconal space.