To study the results of orbital decompression based on the severity of preoperative proptosis.A retrospective noncomparative interventional case series.Thirty-nine orbits in 23 patients with thyroid-related orbitopathy at a university-based referral center.Graded orbital decompression was performed in all patients based on the severity of preoperative exophthalmometry.Exophthalmometry, visual acuity, margin-to-reflex distance, prism cover testing, and intraocular pressure.Mean proptosis reduction in all orbits was 6.4 +/- 2.7 mm (P0.01). In group 1 (preoperative exophthalmometry22 mm), proptosis decreased with a mean of 4.8 +/- 1.3 mm (P0.01); mean proptosis reduction was 6.0 +/- 2.3 mm (P0.01) and 8.9 +/- 3.4 mm (P0.01) in group 2 (exophthalmometry between 22-25 mm) and group 3 (exophthalmometry25 mm), respectively. In four of five eyes with compressive optic neuropathy there was an improvement of best-corrected visual acuity of 2 lines or more. Margin-to-reflex distance of the upper and lower lids and intraocular pressure were reduced in all groups. New-onset diplopia developed in two patients (8.7%); 13 of 15 patients (86.7%) who had diplopia preoperatively had persistent diplopia postoperatively. Two patients (13.3%) had relief of diplopia postoperatively.Graded orbital decompression based on the severity of preoperative exophthalmometry is useful to determine the type and amount of orbital surgery to be performed.
