Optos-guided pattern scan laser (Pascal)-targeted retinal photocoagulation in proliferative diabetic retinopathy

Acta Ophthalmol. 2013 May;91(3):251-8. doi: 10.1111/j.1755-3768.2011.02307.x. Epub 2011 Dec 16.

Abstract

Purpose: To investigate the clinical effects and safety of targeted pattern scan laser (Pascal) retinal photocoagulation (TRP) in proliferative diabetic retinopathy (PDR).

Methods: Prospective and non-randomized study of 28 eyes with treatment-naive proliferative diabetic retinopathy (PDR). Single-session 20-ms-Pascal TRP strategy applied 1500 burns to zones of retinal capillary non-perfusion and intermediate retinal ischaemia guided by wide-field fluorescein angiography (Optos). Main outcome measures at 12 and 24 weeks included; PDR grade (assessed by two masked retina specialists); central retinal thickness (CRT); mean deviation (MD) using 24-2 Swedish interactive threshold algorithm (SITA)-standard visual fields (VF); and ETDRS visual acuity (VA).

Results: Following primary TRP, there was PDR regression in 76% of patients at 12 weeks (κ = 0.70; p < 0.001). No laser re-treatment was required at 4 weeks, and 10 eyes underwent repeat TRP at 12 weeks. Wide-field Optos angiography at 24 weeks showed complete disease regression in 37% and partial regression in 33%. Additional panretinal laser photocoagulation (PRP) was planned for active PDR in 30%. There were significant reductions in CRT over time (10.4 μm at 12-weeks, p = 0.007; 12.1 μm at 24-weeks, p = 0.0003). The MD on VFs improved after 12 weeks (+1.25 dB; p = 0.015) and 24 weeks (+1.26 dB, p = 0.01). The VA increased by +3 letters at 24 weeks (95% CI, 1.74-5.01; p < 0.0001).

Conclusions: This pilot study reports that Optos-guided Pascal 20-ms TRP using 1500 burns for treatment-naive PDR is a promising procedure with favourable safety profile.

Publication types

  • Clinical Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Algorithms
  • Blood Glucose / metabolism
  • Diabetes Mellitus, Type 1 / complications
  • Diabetes Mellitus, Type 2 / complications
  • Diabetic Retinopathy / physiopathology
  • Diabetic Retinopathy / surgery*
  • Female
  • Fluorescein Angiography
  • Fourier Analysis
  • Glycated Hemoglobin A / metabolism
  • Humans
  • Laser Coagulation / methods*
  • Lasers, Solid-State / therapeutic use*
  • Male
  • Middle Aged
  • Prospective Studies
  • Retinal Neovascularization / physiopathology
  • Retinal Neovascularization / surgery*
  • Tomography, Optical Coherence
  • Treatment Outcome
  • Visual Acuity / physiology
  • Visual Fields / physiology

Substances

  • Blood Glucose
  • Glycated Hemoglobin A
  • hemoglobin A1c protein, human