Abstract
Purpose: :
To investigate the value of microperimetric retinal sensitivity in monitoring therapeutic response in the first months of Ranibizumab treatment for choroidal neovascularization (CNV) in patients with age-related macular degeneration (AMD), compared to monitoring of changes in visual acuity and central retinal thickness.
Methods: :
Prospective case series of 8 patients with naïve CNV secondary to AMD receiving monthly intravitreal ranibizumab (0.5 mg/0.05 mL) injections during the first four months of treatment. Best-corrected visual acuity (BCVA), assessed using the Early Treatment Diabetic Retinopathy Study (ETDRS) chart, microperimetry (MP) and central retinal thickness (CRT), obtained using the OCT/SLO-MP (OPKO Health, Miami, Fla) were recorded at baseline and at months 1, 2, 3 and 4 follow-up examinations.
Results: :
Eight patients (age, 75.8±8.3 years; range, 57-88 years) were included. Mean BCVA was 62.4±18.8 letters (range, 33-91 letters) at baseline and 72.3±13.4 letters (range, 57-85 letters) (P = 0.02) at month 4. Mean BCVA improved after 1st and 2nd injections and remained almost unchanged after 3rd and 4th injections. Mean MP scores were 8.75±4.9 (range, 0.7-16.1) at baseline and 11.5±5.5 (range, 1.25-16.25) (P=0.016) at month 4. Mean retinal sensitivity progressively improved during the first four months of treatment with the most significant increases of the mean MP scores being recorded following the 1st and 4th injections. Central retinal thickness decreased from 340.6±52.9 microns at baseline to 264.0±38.2 microns at 4 months (P = 0.01). A monthly analysis of the mean CRT change showed substantial improvement following the 1st injection which remained essentially unchanged. Plots of mean MP and ETDRS scores showed significant correlation (r = 0.69, p<0.001), as did MP and central macular thickness (r = 0.528, p=0.01). Correlation between ETDRS score and central macular thickness was less significant(r=0.33, p=0.043).
Conclusions: :
Retinal sensitivity, in the first months of Ranibizumab therapy appears to continue to improve progressively with monthly treatments, while central retinal thickness and visual acuity improved following the first injection and remain almost unchanged afterwards. Microperimetry appears to correlate better with CRT than ETDRS and may provide better indication of retinal functional improvements in neovascular AMD patients treated with Ranibizumab. A larger study is in progress to confirm these findings
Clinical Trial: :
http://www.clinicaltrials.gov NYEE-07.14
Keywords: perimetry • age-related macular degeneration • vascular endothelial growth factor