Abstract
Purpose:
To evaluate the safety and efficacy of subthreshold micropulse diode laser as monotherapy for mild to moderate diabetic macular edema.
Methods:
This was a retrospective chart review of 11 patients with mild to moderate, non-ischemic, non-tractional diabetic macular edema observed on clinical exam and confirmed by spectral domain optical coherence tomography with a central macular thickness of less than 400 microns. Best-corrected visual acuity (BCVA) ranged from 20/30 to 20/80. None of the patients had received treatment for diabetic retinopathy in the previous six months. Subthreshold micropulse diode laser (577 nm) was performed with a 5% duty cycle and power ranging from 80-160 mw with a spot size of 100 microns. Best-corrected visual acuity (BCVA) and central macular thickness were compared at baseline and at 4 months. Careful documentation was performed to look for appearance of new focal scars during the follow up visits.
Results:
The preoperative best-corrected visual acuity and central macular thickness ranged from 20/30 to 20/80 and 285 +/- 82 microns respectively. At 4 months, visual acuity was gained or maintained within 1 line in 8 of the 11 patients (72.7%). The central macular thickness improved to 274 +/- 76 microns in 9 of the 11 patients (81.8%). No new laser scars were detected in any patient.
Conclusions:
Subthreshold micropulse diode laser appears to be safe and effective in controlling mild to moderate diabetic macular edema. The absence of detectable focal scars theoretically allows safe retreatment if necessary, while preserving macular function. Combination with anti VEGF therapy might be a valuable option in cases of severe and diffuse diabetic macular edema. Further studies with larger patient groups are needed in the future.
Keywords: 499 diabetic retinopathy •
505 edema •
688 retina