Purpose: Cryotherapy, the most common modality used to create a chorioretinal adhesion during retinal reattachment surgery, is associated with the dispersion of viable pigment epithelial cells and breakdown of the blood-ocular barrier, which are thought to be causative in a number of postoperative events, including macular pucker, proliferative vitreoretinopathy (PVR), and cystoid macular edema. Transscleral diode laser has been used successfully to create a chorioretinal adhesion in retinal reattachment surgery (diopexy) and experimentally has been shown to cause less pigment dispersion and blood-ocular barrier breakdown than cryotherapy. The authors carried out a prospective randomized study to compare the results and complication rates of transscleral diopexy with those of cryopexy during surgery for rhegmatogenous retinal detachment (RRD).
Methods: Data from 120 patients with recent onset RRD without significant PVR who were suitable for scleral buckling surgery and randomized to treatment using diode laser or cryotherapy were analyzed. The primary outcome measure was reattachment at 6 months with one operation. Secondary outcome measures were pain and swelling on the first postoperative day, cystoid macular edema as assessed angiographically at 6 weeks, and visual acuity, macular epiretinal membrane, and pigment migration under the fovea at 3 months.
Results: There was no significant difference between the primary and secondary outcome measures between the two treatment groups, with a primary success rate of 83% in the diode group and 92% in the cryotherapy group. Pain and postoperative swelling on the first postoperative day were equivalent. Cystoid macular edema was angiographically present in 12% in the diode group and 14% in the cryotherapy group. Visual acuity of at least 20/40 was achieved in 54% of patients in both groups. The rate of PVR was 5% in the diode group and 3% in the cryotherapy group.
Conclusion: In this study of patients with uncomplicated RD without significant preoperative PVR, the experimentally shown benefits of transscleral diode laser did not result in significant improvement in the results of reattachment surgery compared with cryotherapy.