Graded Decompression of Orbital Fat and Wall in Patients with Graves’ Orbitopathy

Abstract

Purpose: To investigate the results of graded decompression of orbital fat and walls in Graves’ orbitopathy(GO) considering the degree of proptosis reduction at surgery and preoperative computed tomography (CT)findings. Methods: This is a retrospective interventional case series. Graded orbital fat and wall decompression was performedin 90 orbits of 55 patients. In patients with enlarged extraocular muscles and minimal orbital fat proliferationin preoperative CT scans, one- or two-wall decompression of posterior orbit was performed with minimalfat excision. In other cases, the maximal amount of fat tissue was removed from the post-septal area to theapex. If the proptosis was not satisfactorily symmetrically reduced at surgery, one- or two-wall decompressionwas performed successively. Symmetric reduction of proptosis was consistently confirmed intraoperatively toassure that a desired amount of exophthalmos reduction was achieved. Results: Four types of decompression were performed: fat only (group 1), fat and one-wall (group 2), fat andtwo-wall (group 3), and two-wall and minimal fat decompression (group 4). The mean preoperative Hertelvalue (20.6 ± 2.8 mm) was reduced significantly at six months postoperatively (16.1 ± 2.3 mm). Proptosis significantlydecreased with a mean of 4.3 ± 1.7 mm, and the reduction was greatest (5.1 ± 2.1 mm) in group 3. Ingroup 1, a significant correlation between Hertel change and the volume of resected orbital fat was found (r =0.479). Diplopia was newly developed or aggravated postoperatively in eight patients, and six of these patientswere in group 3. With the exception of one patient, visual acuity improved to nearly normal postoperatively inall patients with optic neuropathy. Conclusions: Graded orbital decompression of orbital fat and bony walls, as assessed by the degree of proptosisreduction during surgery, was effective and predictable with minimal complications in GO patients withvision-threatening or cosmetically disfiguring proptosis.