• Written By: Vincent A. Deramo, MD

    The results of this retrospective comparative case series suggest that treatment of newly-diagnosed high-risk proliferative diabetic retinopathy (PDR) with panretinal photocoagulation (PRP) with traditional laser settings is less effective when using the pattern scan laser (PASCAL) than the traditional argon laser.

    The authors reviewed the cases of 41 eyes with high-risk PDR treated with the argon green laser and 41 eyes treated with the PASCAL. The patients were followed for at least six months, although follow-up in the argon laser group was on average longer (410 days) compared with the PASCAL group (313 days).

    Although both groups received a similar number of spots (1,438 with PASCAL vs. 1,386 with argon laser; P = 0.59), those treated with PASCAL were more likely to experience persistence or recurrence of neovascularization within six months (73 vs. 34 percent; P < 0.0008). However, the study was not adequately powered to evaluate the incidence of vitreous hemorrhage, neovascularization of the iris, neovascular glaucoma or need for vitrectomy.

    The authors conclude that when using traditional laser settings, PRP performed with the PASCAL is less effective than traditional argon laser at achieiving lasting regression of retinal neovascularization in the setting of previously untreated high-risk PDR. They say that physicians may need to change treatment parameters when using PASCAL pattern laser therapy for this condition. Increasing the number, spot size or duration of laser burns may improve the efficacy of PASCAL as measured by rates of regression and recurrence of neovascularization.