Abstract
Purpose: :
A prospective study of ten pateints with diabetic macular edema (DME) treated with monthly injections of Pegaptanib sodium 0.3mg (Macugen) for 2 months was performed. Weekly OCT testing was done for 8 weeks to determine the time of the peak response.
Methods: :
Patients were enrolled in the study if they were 18 or older with central DME on OCT ≥ 275 mc., and ETDRS best corrected visual acuity in the range of 20/40-20/400. Exclusion criteria included active proliferative diabetic retinopathy, media opacities, laser and/or intraocular injection within 3 months of screening, vitreoretinal surgery, iris neovascularization, other retinal disease involving the macula, ocular inflammation and aphakia.
Results: :
Of the 10 enrolled, 9 completed the study. One patient developed a preretinal hemorrhage which precluded accurate OCT measurements for weeks 6-8. Seven of the 10 showed a response with reduction in macular thickness. Overall, an immediate mean response was seen with a reduction in macular thickening which persisted over the 8 weeks. The maximum reduction during each cycle was seen in the second week. The mean gains seen at week 2 lessened by week 4. There was a strengthened response following the 2nd injection with the maximum response seen at week 6 and a lessening of gains by week 8.Mean vision gains were also seen starting at the first post-injection week with an initial mean gain of approximately 6 letters. The maximum mean vision gain was seen at 4 weeks. The vision gain diminished by week 8 to approximately 1 letter.The compications included 1 myocardial infarction, 1 eye with vitreous hemorrhage, and 1 eye with progression of lens changes.
Conclusions: :
The maximum treatment reduction in diabetic macular edema with Macugen is seen 2 weeks after the injection. The response decreases after that suggesting that injecting every 4 weeks is more effective than every 6 weeks. There is also a corresponding gain in vision following Macugen injections. At the conclusion of our 2 month study, all patients still showed significant edema indicating the importance of continuing treatment beyond 2 months.
Keywords: diabetic retinopathy • edema • imaging/image analysis: clinical