Abstract
Purpose: :
To compare optical coherence tomography (OCT)-measured retinal thickness and visual acuity in eyes with proliferative diabetic retinopathy (PDR) after pars plana vitrectomy (PPV).
Methods: :
Institutional review board approved single surgeon retrospective study of 31 consecutive eyes with PDR. Retinal thickness was measured with optical coherence tomography (OCT) (Stratus or Cirrus OCT, Carl Zeiss Meditec, Inc): automated central 1 mm subfield thickness and the manually measured central foveal point (CFP) thickness and correlated with visual acuity.
Results: :
Mean preoperative visual acuity was 20/200 (range: LP to 20/80), mean post operative follow up was 23 months (range: 8 to 42 months). Mean post operative best corrected visual acuity improved to 20/60 (range: CF to 20/25, p<0.0001) with mean OCT 1 mm subfield thickness 249 micron while manual CFP 277 micron. The correlation coefficients (r) for logmar visual acuity versus OCT automated central 1 mm subfield thickness was 0.34 (P=0.027) and that for logmar visual acuity versus OCT CFP was 0.37 (P=0.043).
Conclusions: :
The present study suggests that there is modest correlation between OCT-measured central 1 mm sub field thickness and CFP and visual acuity, following PPV for PDR. Thus, although OCT measurements of retinal thickness represent an important tool in clinical evaluation, they cannot substitute reliably as a surrogate for visual acuity.
Keywords: diabetic retinopathy • imaging methods (CT, FA, ICG, MRI, OCT, RTA, SLO, ultrasound) • macula/fovea