Orbital decompression for thyroid orbitopathy

Background: Severe thyroid orbitopathy may result in optic neuropathy, corneal exposure and disfiguring proptosis. Orbital decompression has most commonly been performed for optic neuropathy, but with improved techniques, more patients are undergoing decompression for other indications. Purpose: This report evaluates the results and morbidity of orbital decompression for thyroid orbitopathy performed by one surgeon. Methods: The records of 33 patients (53 orbits) undergoing orbital decompression for thyroid orbitopathy were analysed for changes in visual acuity and colour vision (where the indication was optic neuropathy) and reduction in proptosis. Complications were also analysed. Results: Visual acuity and colour vision improved in all 33 eyes with optic neuropathy in the short term postoperative period (4 weeks), but later deteriorated in five eyes (6.6%) of 4 patients (19%). Proptosis decreased by a mean 5.3 mm (range, 1-10). Diplopia developed or worsened overall in 10 of 33 patients (30%), but only in one of 12 (8%) where the indication was cosmesis or corneal exposure. Diplopia improved in 2 of 33 (6%). All patients with symptomatic diplopia achieved binocular single vision in a useful range after one and sometimes two squint procedures. No patient lost vision as a result of surgery. Conclusions: Orbital decompression is effective in improving vision in most patients with thyroid optic neuropathy, but induces or worsens diplopia in a high proportion of these patients. Proptosis can be effectively and dramatically improved.