Poster Tae Gon Lee

Purpose:

To compare the clinical results of pattern scan laser (PASCAL) versus conventional panretinal photocoagulation (PRP) for the management of proliferative diabetic retinopathy (PDR).

Methods:

Retrospective review of the medical records was performed on 379 consecutive eyes with newly diagnosed PDR that underwent PRP using either PASCAL (160 eyes treated between June 2008 and April 2011) or conventional laser (219 eyes treated between November 2005 and May 2008), then underwent fluorescein angiography at 12 months after initial treatment. We compared the clinical results including 1) persistence or recurrence of retinal neovascularization, and 2) the incidence of vitreous hemorrhage (VH), neovascularization of iris (NVI), neovascular glaucoma (NVG), and macular edema (ME). The laser setting parameters for both groups were also compared.

Results:

Preoperative systemic and ocular data were similar between two groups. Mean age was 56 and 60 years in PASCAL and conventional PRP group, respectively. There was no significant difference between two groups for persistence or recurrence of retinal neovascularization within 12 months of initial treatment with 6/160 eyes (3.8%) and 16/219 eyes (7.3%) in PASCAL and conventional PRP group, respectively (p=0.633). The incidence of VH, NVI, and NVG were similar between two groups. However, the incidence of ME was lower in PASCAL group (49/160 eyes, 30.6%) than conventional PRP group (96/219 eyes, 43.8%) (p=0.038). The laser parameters were different between two groups and were as follows: mean number of treatment = 2.3 and 3.0, mean total number of laser burn = 1852 and 1273, mean duration of laser = 27 and 193msec, mean laser power = 397 and 227mW, mean total laser energy = 4633 and 10993mJ in PASCAL and conventional laser group, respectively (p<0.001 in all laser parameters).

Conclusions:

Both PASCAL and conventional PRP showed similar effect on inducing and maintaining regression of retinal neovascularization over 12 months in treatment-naïve PDR with the laser parameters used in this study. On the other hand, incidence of ME was lower in PASCAL group than conventional PRP group. There was no significant difference between two groups in terms of other events such as NVI, NVG, or VH.