Abstract
Purpose:
To determine the effect of combination therapy with intravitreal anti-vascular endothelial growth factor (anti-VEGF) injections and subthreshold diode micropulse (SDM) laser photocoagulation on visual outcomes and the anti-VEGF treatment burden in patients with diabetic macular edema (DME).
Methods:
A retrospective chart review was performed of all patients with subfoveal DME identified by spectral domain optical coherence tomography (SD-OCT) and fluorescein angiogram (FA) who had undergone SDM laser and/or anti-VEGF injections in the time period between January 2011 to June 2014. Exclusion criteria included the presence of other concomitant retinal diseases that can lead to subfoveal macular edema, a history of intravitreal corticosteroid injections, or conventional laser in the previous 2 years. Twenty patients were identified. Group 1 consisted of 10 patients who had undergone both SDM laser and anti-VEGF injections. Group 2 consisted of 10 patients matched for age, gender and a diagnosis of subfoveal DME who had undergone anti-VEGF monotherapy. All records were reviewed for BCVA, fundus photography, FA, macula SD-OCT, and the type and frequency of treatments administered. Statistical analysis was performed using the paired student t-test.
Results:
Groups 1 and 2 included a total of 20 patients. The average age of Group 1 was 65 years and that of Group 2 was 62 years. Duration of follow-up ranged from 6 to 18 months (average 9.6 months, median 8 months) for Group 1 and 6 to 29 months (average 13.1 months, median 12 months) for Group 2. Average number of injections given per month was 0.27 for Group 1 and 0.67 for Group 2 (p=0.004). The average initial CMT was 315.5um for Group 1 and 419.2um for Group 2 (p=0.03). Average CMT improvement was 39um in Group 1 and 117um in Group 2 (p=0.04). There was no significant difference in the average final CMT between the two groups. BCVA improved 0.05 logMAR in Group 1 and 0.08 logMAR in Group 2 (p=0.27).
Conclusions:
The frequency of anti-VEGF injections was significantly reduced in patients who had undergone combination therapy with SDM laser without a significant difference in visual outcomes.