This is a retrospective review of 95 eyes of 54 patients undergoing orbital decompression for Graves’ orbitopathy. All patients had a swinging eyelid approach across the whole of the lower lid. Thirty-six eyes also had insertion of a 0.3mm thick AlloDerm graft into the lower lid (group 1), 33 eyes had inferior retractor recession without a graft (group 2), and the remaining 26 eyes underwent decompression alone (group 3). The patients were not randomised, but the retractors were recessed when there was significant scleral show at closure, and an AlloDerm graft employed when this was marked and / or not corrected by retractor recession alone. Preoperative MRD2 (distance from the centre of the pupil to the lower lid margin in primary gaze) was significantly higher in group 1 (8.0mm) than groups 2 (6.6mm) or 3 (6.0mm). There was a significant difference in the improvement in lower lid retraction with group 1 having a reduction on MRD2 of 2.7mm compared with 1.8mm for group 2 and 1.2mm for group 3. There was no significant difference between the groups in reduction in proptosis.
Although the study numbers are good there is an inherent bias in the procedure selection process as only those with the most lid retraction underwent grafting. It could be argued these patients had greater potential for an improvement whatever technique was used. In addition the authors make no mention of whether any squint surgery was required which could also affect the lower lid position; this being the main reason why lid surgery is conventionally performed as a final procedure.