Transconjunctival Extirpation of a Voluminous Orbital Cavernoma: 2-Dimensional Operative Video.

Purely intraorbital cavernomas remain rare, but still are the most common benign orbital tumors.1 These expansive lesions are now rapidly detected and adequately treated. Surgical resection is the gold standard and a definitive solution. The choice of approach varies between different possibilities, including orbitotomies, trans-sinusal routes, and transconjunctival accesses.2-4 Because the last technique is less known to the neurosurgeon, we describe here a step-by-step guide to perform it.  The technique is illustrated with the case of a 62-yr-old male with a voluminous right retroocular cavernoma. He presented a progressive right exophthalmia without visual acuity or campimetric deterioration. Because the cavernoma was purely medial from the optic nerve in the intraconal space, no osteotomy was deemed necessary to extirpate the lesion. The video shows the conjunctival dissection, followed by the medial rectus muscle being dissected, allowing us to attain the retrobulbar space in the orbit. The cavernoma is then dissected from the surroundings and reduced in volume by coagulation so its removal does not apply hyperpressure on the adjacent fragile structures. We then pursue with the closure by stitching the medial rectus muscle to the eyeball. Finally, the conjunctiva is sutured.  Postoperatively, there was no complication. A transient mydriasis due to ciliary nerve manipulation spontaneously resolved. Extirpation of the lesion was total. The patient's exophthalmia normalized over the next months. No visual or campimetric deterioration was noted at follow-up. A slight horizontal diplopia was noted after surgery, which normalized at 1 yr. The patient's consent was obtained for the procedure.