Title

SHORTPULSE LASER PHOTOCOAGULATION PLUS SUBTHRESHOLD MICROPULSE LASER ASSOCIATED WITH RANIBIZUMAB FOR THE TREATMENT OF DIABETIC MACULAR EDEMA (THE SANDWICH GRID TECHNIQUE)

Introduction

To verify the effects of two laser treatment procedures combined, short pulse grid laser (SP) and subthreshold micropulse laser (MP), the sandwich grid technique (SWG) plus intravitreal ranibizumab (IVR) on central subfield thickness (CSFT), Best-corrected visual acuity (BCVA) and macular sensitivity threshold in patients with diabetic macular edema (DME).

Methods

Thirty-three patients (45 eyes) with DME were treated with the SWG laser technique plus IVR and followed for 12 months. Laser treatment was performed at baseline: SP laser spots were placed in macular area (500 μm from the fovea) and number of spots varying according to the extension of DME; subsequently MP laser was delivered up to the edge of the fovea. MP laser recurrent sessions could be performed every 3 months if necessary. IVR injection was performed at baseline and repeated monthly if CSFT > 300μm. Preoperatively and monthly, ophthalmological examination was performed including measurements of BCVA, CSFT and retinal sensitivity.

Results

Twenty-seven patients (37 eyes) completed 1 year of follow-up. Mean ± SE CSMT (µm) was 509.36 ± 25.14 and 325.76 ± 15.34 at baseline and 12 months, respectively. A statistically significant reduction in mean CSFT was observed at all study visits compared to baseline (p<0.001). Mean ± SE BCVA (logMAR) was 0.62 ± 0.04 and 0.45 ± 0.04 at baseline and 12 months, respectively. A significant improvement in mean BCVA was observed compared to baseline (p<0.001). Mean ± SE retinal sensitivity was 17.85 ± 0.80 and 19.05 ± 0.59 at baseline and 12 months, respectively. The mean retinal sensitivity trended to improve after one year of follow-up (p=0.058). The mean number of IVR injections was 8.29 ± 0.63. The mean number of MP laser procedures including initial SWG laser session was 3.67 ± 0.22. No ocular or systemic adverse effects were observed.

Discussion

Current data indicate that the SWG laser technique plus IVR seems to be effective to reduce CSFT and improve BCVA in patients with center-involving DME

Keywords

retina, macula, edema, macular edema, diabetic macular edema, laser, micropulse, antiangiogenic, ranibizumab

Area

CLINICAL CASE

Authors

Renato Peroni, José Augusto Cardillo, Tomás Oliveira Castro Teixeira Pinto, Rafael Memória, Lucélia Albieri, Francyne Veiga Reis Cyrino, Rodrigo Jorge