Abstract
Purpose: :
To examine the relationship between baseline thickness of the neurosensory retina, retinal pigment epithelium (RPE) and choroid and baseline visual acuity and change in acuity after 6 months of ranibizumab therapy for choroidal neovascularisation secondary to age-related macular degeneration (ARMD).
Methods: :
Patients with CNV secondary to ARMD were treated with three consecutive injections of ranibizumab, followed by further injections as required. ETDRS letter score and Stratus OCT (Zeiss) Macular Thickness or Fast Macular Thickness scans were obtained at baseline and all subsequent visits. The thickness of the neurosensory retina, RPE and choroid in the central 1mm subfield was measured with the OCTOR software (Doheny Eye Institute). Pearson correlation coefficient was used to assess the association between baseline acuity and change in acuity after 6 months of therapy with each of the retinal thickness measures
Results: :
Baseline and follow-up acuity and retina or choroidal thickness was recorded for 30 patients with CNV secondary to ARMD. Baseline mean acuity was 46.7 ETDRS letters (range 24-61 letters) and, after 6 months of therapy, mean acuity was 51.86 ETDRS letters (range 25-76 letters). Baseline visual acuity was not associated with the baseline thickness of either the central neurosensory retina (r = -0.274, p= 0.175) or RPE (r = -0.035, p = 0.866) but was associated with increasing central choroidal thickness (r=0.557, p=0.002). There was a non-significant trend in favour of an association between acuity change after 6 months and the baseline thickness of the central RPE (r = 0.379, p=0.056). No association was observed between visual acuity change and baseline thickness of either the central neurosensory retina (r = -0.094, p=0.648) or choroid (r =-0.269, p=0.183).
Conclusions: :
For patients with CNV secondary to ARMD, baseline visual acuity is associated with the baseline thickness of the central choroid. A non-significant trend exists to support an association between visual acuity change after 6 months of ranibizumab therapy and baseline thickness of the central RPE. Analysis of baseline OCT images may help to predict functional response to ranibizumab therapy.
Keywords: age-related macular degeneration • choroid: neovascularization