Abstract
Purpose :
Subthreshold micropulse laser is increasingly gaining traction as a treatment for diabetic macular edema. The actual damage to tissue is very variable and typically no damage is observed by the examiner. An Iridex Micropulse 532 laser was acquired at our facility, and a study designed to assess the efficacy of subthreshold macular laser against our established treatment of intravitreal bevacizumab in the initial treatment of diabetic macular edema.
Methods :
Data collected on 25 eyes using retrospective chart review of patients presenting to the resident led Retina clinic with new onset DME. All patients received an initial baseline OCT with measurement of the central macular thickness (CMT), followed by either an intravitreal injection of bevacizumab or underwent sub threshold macular laser (STML – Iridex 532) with 1 month follow up. Response was monitored by change in BCVA and CMT.
Results :
Total of 25 eyes received treatment with intravitreal injection of bevacizumab or sub threshold macular laser for new onset DME. Average preinjection CMT ranged from 310 to 705 in the injection group, with results suggesting a dramatic improvement in CMT of 220 to 402, representing 42% reduction in CMT (p<0.01). Average improvement in BCVA was 2 lines or better (p<0.02). In the subthreshold laser group response was not always present with 7 eyes in which CMT increased following treatment, and in those eyes in which there was an improvement, CMT changed from baseline only 12% (p<0.01).
Conclusions :
In the resident led clinic, intravitreal injections are highly effective in the initial treatment of DME with excellent reduction in CMT, and BCVA compared to sub threshold macular laser. Initial data from long term follow up however shows further reduction in the sub threshold laser group, and this therapy shows promise as an adjunctive treatment for the long term management of DME.
This is an abstract that was submitted for the 2018 ARVO Annual Meeting, held in Honolulu, Hawaii, April 29 - May 3, 2018.