Clinical Profile and Visual Outcomes after Treatment in Patients with Dysthyroid Optic Neuropathy

PURPOSE To report the clinical data and visual outcomes after treatment of patients with dysthyroid optic neuropathy (DON). METHODS We retrospectively reviewed the medical records and orbital images of 40 patients (65 eyes) with DON and analyzed the visual outcomes after treatment with intravenous steroids pulse therapy, radiotherapy and orbital decompression. RESULTS The study included 21 men and 19 women, with 10 (25%) being diabetic patients. Visual field test results revealed defects in 88.7% of DON eyes; afferent pupillary defects in 63.2%; reduced color vision in 78.5%; and abnormal visual evoked potentials in 84%. Orbital imaging showed moderate to severe apical crowding in 95% of the orbits and intracranial fat prolapse in 24.2%. Median best corrected visual acuity improved from 0.4 to 1.0 after one year of treatment (p < 0.001). We noted more improvement in vision with the use of decompressive surgery than with non-surgical methods (p < 0.05). Recurrences occurred in 7 patients who had not received orbital radiotherapy. CONCLUSIONS Visual field defects and apical crowding seen on orbital imaging were the most sensitive indicators for the detection of DON. Treatment with intravenous steroids pulse therapy, radiotherapy and orbital decompression effectively improved visual outcomes in cases of DON.