Superomedial lid crease approach to the medial intraconal space: a new technique for access to the optic nerve and central space.

Abstract

To present clinical and cadaver studies of a new approach to the medial intraconal space. We retrospectively review our clinical results by using a new technique to gain access to the medial intraconal space through a superomedial lid crease incision. We also use cadaver dissection studies to compare this new approach with the medial transconjunctival approach, the lateral orbitotomy without bone-flap, and the lateral orbitotomy with bone-flap. Access to the medial intraconal orbital space through the superomedial lid crease incision allowed optic nerve sheath fenestration or biopsy in 18 eyes with few postoperative complications. One case of tonic pupil, one case of transient vertical diplopia, and two cases of transient medial ptosis were seen. Five cavernous hemangiomas were removed from the intraconal space with this approach, with one case of transient vertical diplopia and one case of transient medial ptosis. The cadaver studies showed that when the superomedial lid crease approach is used, the tangent angle with the optic nerve and the incision-to-nerve distance measurements compare favorably with the medial transconjunctival and the lateral orbital approaches. The superomedial lid crease approach to the medial intraconal space has a number of advantages over the medial transconjunctival and lateral orbital approaches, including ease of dissection, incision-to-nerve distance, and angle of approach to the optic nerve. This technique allows for optic nerve sheath fenestration or tumor removal from the central space with few complications.