Abstract
Purpose: :
To evaluate the effect of pegaptanib sodium intravitreal injections performed every 4 weeks (Q4 arm) and every 6 weeks (Q6 arm) on macular sensitivity as measured by microperimetry in patients with diabetic macular edema (DME).
Methods: :
Records of 12 patients from the PRESerVe study, who had microperimetry testing done at baseline (day 1) and at the end of the study (week 24), were reviewed. There were 8 patients from the Q4 arm and 4 patients from the Q6 arm. The microperimeter used was Nidek MP-1 with standardized testing protocol established by the Vienna Reading Center (Vienna, Austria) which measures sensitivity of 29 spots in macula on a scale from 0 to 20 decibels (dB). Mean values of all 29 scores and also of the subset of 5 central scores were calculated for the 2 arms.
Results: :
The means of the central scores in the Q4 arm and Q6 arm were 4.93 dB (standard deviation (SD) 3.94, median 4.1, range 0-13.0) and 7.85 dB (SD 6.32, median 8.5, range 0-14.4) respectively on baseline testing and 4.43 dB (SD 3.08, median 4.2, range 0-8.0) and 6.25 dB (SD 5.18, median 3.8, range 3.4-14.0) respectively on the final testing. For the total scores the means in the Q4 arm and Q6 arm were 6.01 dB (SD 4.11, median 4.9, range 0-12.1) and 10.89 dB (SD 4.61, median 11.7, range 4.6-15.6) respectively on baseline testing, and 5.51 dB (SD 3.10, median 5.2, range 0.5-9.8) and 10.37 dB (SD 2.62, median 11.3, range 6.6-12.2) respectively on the final testing.
Conclusions: :
Overall, the macular sensitivities as measured by MP-1 were essentially preserved through the study period in both arms. Minimal decrease in sensitivities were noted in both study arms. The sensitivity appears to have dropped less in the central area in the Q4 arm than the Q6 arm (0.50 dB vs. 1.60 dB drop). Similar results were found in other studies that evaluated macular sensitivity with microperimetry with use of anti-angiogenics. Small sample size precludes the evaluation of statistical significance in this study.
Keywords: edema • injection • diabetic retinopathy