Abstract
Purpose :
Much controversy exists regarding the role of laser in the treatment of DME. Focal macular laser, as described in the Modified-ETDRS Protocol, was delivered historically in a high-intensity, low-density fashion. Innovation in laser delivery mechanisms brought forth subthreshold micropulse laser, the application of which is characterized by a low-intensity, high-density fashion. Herein we explore the utility and durability of a single application of low-intensity, low-density focal macular laser in the treatment of DME.
Methods :
This retrospective chart review followed patients with baseline vision 20/40-20/100 undergoing low-intensity, low-density laser for DME . Treatment was administered utilizing 532nm diode laser with standardized parameters of 70mW, 50um, and .05sec. Data were obtained at 1, 3, and 6 months following treatment.
Exclusion criteria were 1) retinal laser or intravitreal injection in the 3 months preceding treatment 2) retinal laser or intravitreal injection in the 6 months following treatment 3) comorbid retinal pathology 4) failure at collection of data at more than 2 follow-up visits.
Functional response was measured using ETDRS Visual Acuity (VA). Anatomic metrics measured on Heidelberg Spectralis OCT (Heidelberg Instruments Heidelberg, Germany) included Central Macular Thickness (CMT), Maximum Macular Thickness (MMT), Total Volume (TV), and maximum retinal thickness at the area of the macula treated, heretofore referred to Maximum Treated Area (MTA).
Results :
42 patients met inclusion criteria. A mean of 8.4 laser applications were administered. Baseline characteristics were a mean VA 68.43, MMT 309.50um, CMT 400.62um, TV 8.79mm3, and MTA 435.00um.
At 1 month, of 41 patients with data obtained, we observed a mean change from baseline of VA 0.1, MMT 6.05um, CMT -0.20um, TV -0.02mm3, and MTA -18.46um.
At 3 months, of 31 patients with data obtained, we observed a mean change from baseline of VA 2.0, MMT -27.26um, CMT -29.61um, TV -0.22mm3, and MTA -48.48um.
At 6 months, of 22 patients with data obtained, we observed a mean change from baseline of VA 3.09, MMT -14.27um, CMT -27.23um, TV -0.26mm3, and MTA -53.68um.
Conclusions :
Low-intensity, low-density focal macular laser is an effective means in reversing vision loss from DME. Further, this a single treatment attains profound, sustained, and progressive anatomic results.
This is an abstract that was submitted for the 2017 ARVO Annual Meeting, held in Baltimore, MD, May 7-11, 2017.