Abstract
Purpose: :
To investigate the utility of combined orbital and skull-based endoscopic surgical decompression of the optic nerve in patients rendered legally blind from dysthyroid optic neuropathy (DON).
Methods: :
Retrospective, non-comparative, interventional case series. Consecutive patients diagnosed with DON from extraocular muscle enlargement causing apical crowding of the optic nerve who presented for treatment over an eight-year period were included. Pre- and postoperative measurements of visual acuity, color vision, pupil response to light, extraocular movements, and intra-ocular pressure were assessed and compared.
Results: :
Four of three hundred eighty one patients who presented for ophthalmic plastics evaluation over the study period had vision loss to the level of legal blindness in one or both eyes. All four patients underwent emergent skull base decompression of the optic nerves and intravenous steroid treatment.Changes in color vision, pupil response to light, extraocular movements, and intraocular pressure were not statistically significant. Visual acuity improved in all patients. Of the 6 legally blind eyes (3 OD and 3 OS) the mean LogMAR scores before and after decompression were 1.55 and 0.37, respectively (SD= 0.80 and 0.31, respectively). The mean change in LogMAR visual acuity was 1.18 (P= .0079). When analyzing all eyes (N=8), the change in visual acuity remained statistically significant (P= 0.0197).
Conclusions: :
Blindness from DON is potentially reversible with emergent decompression of the skull base component of the orbital apex and optic canal through a combined endoscopic and orbital approach to the optic nerves.
Keywords: optic nerve • autoimmune disease • visual acuity