Background: To compare the effectiveness of subthreshold grid laser treatment (SGLT) with infrared micropulse diode laser alone or in combination with intravitreal triamcinolone injection (SGLT-IVTJ) for the treatment of macular edema (ME) secondary to branch retinal vein occlusion(BRVO)
Methods: Pilot randomized clinical trial including 24 patients (24 eyes) who were randomized either to the SGLT (13 eyes), or to SGLT-IVTJ (11 eyes). Complete ophthalmic examinations, including ETDRS visual acuity, OCT, and fluorescein angiography were performed at the moment of the study entry and at 3-month intervals, with a planned follow-up of 12 months. Main Outcome measures were the decrease in mean foveal thickness (MFT) on OCT, and the proportion of eyes that gained at least 10 letters (approximately 2 or more lines of visual acuity gain) at the 12-month examination. Secondary outcomes were the decrease in mean total macular volume on OCT, and the timing of ME resolution.
Results: The change in MFT from the initial values was statistically significant for the SGLT-IVTJ from the 3-month examination and for the SGLP from the 6-month examination (P <0.001). At the 12-month evaluation 10 patients of the SGLT-IVTJ group (91%) and 8 of the SGLT group (62%) gained at least 10 letters (2 lines) in visual acuity. The mean number of lines gained was 3.4 and 1.3 in the SGLT-IVTJ and in the SGLT group, respectively.
Conclusions: The combined SGLT-IVT treatment of ME secondary to BRVO allows a significant visual acuity improvement, when compared with simple grid laser treatment.