• Proportion of subjects improving >/= 15 letters (3 lines) of best-corrected distance visual acuity at 18 weeks after initiation of pegaptanib. Distribution of visual acuity changes at 18 weeks after initiation of pegaptanib [ Time Frame: 18 weeks after enrollment ] [ Designated as safety issue: No ]
  
• Distribution of absolute levels of distance visual acuity at 18 weeks after initiation of pegaptanib [ Time Frame: 18 weeks after enrollment ] [ Designated as safety issue: No ]
  
• Analysis of time to 15 letter improvement of best-corrected distance visual acuity through 18 weeks after initiation of pegaptanib using a 2-state stochastic model to account for events and recoveries from events [ Time Frame: 18 weeks after enrollment ] [ Designated as safety issue: No ]
  

• Analysis of decrease in retinal thickness by OCT at 18 weeks after initiation of pegaptanib [ Time Frame: 18 weeks after enrollment ] [ Designated as safety issue: No ]
  
• Analysis of improvement of fluorescein leakage seen on fluorescein angiography at 18 weeks after initiation of pegaptanib [ Time Frame: 18 weeks after enrollment ] [ Designated as safety issue: No ]
  
• Additional changes 12 weeks after discontinuation of pegaptanib (6 months after study entry) [ Time Frame: 6 months after enrollment ] [ Designated as safety issue: No ]
  

While only 1% to 2% of people following cataract surgery develop visual acuity loss from chronic post-surgical cystoid macular edema (CME), this represents approximately 20,000 individuals in the U.S. each year, and many more throughout the world. No current drug or surgical treatment is very effective in the management of chronic post-surgical CME. Topical non-steroidal anti-inflammatory medications, such as ketorolac drops 4 times a day (qid) for 3 months, have been shown to reduce the extent of fluorescein leakage on angiography in patients with this condition; however, compliance can be difficult, not all cases resolve following this treatment, the drop is not approved for this indication, and it is unknown if this treatment has an effect that lasts beyond 3 to 6 months. The fluorescein angiographic findings and the effects of ketorolac drops suggest that the condition is a result of increased permeability from inflammation and might resolve with a therapy that decreases abnormal vessel permeability. Recent studies have shown that vascular endothelial growth factor (VEGF) plays a major role in vessel permeability. Pegaptanib (Macugen) is an FDA-approved drug for wet AMD. Pegaptanib is a selective VEGF antagonist that blocks the effects of VEGF; therefore,pegaptanib may decrease vessel permeability and possibly decrease CME. Pegaptanib has been shown to have some activity in reducing retinal blood vessel leakage in diabetic patients with chronic macular edema (Macugen Diabetic Retinopathy Study Group. A phase II randomized double-masked trial of pegaptanib, an anti-vascular endothelial growth factor aptamer, for diabetic macular edema. Ophthalmology 2005;112:1747-57.), further supporting the hypothesis that it might be effective in other causes of chronic macular edema. We plan to conduct a pilot study of the effects of pegaptanib (up to 3 treatments of pegaptanib given as often as every 6 weeks for up to 12 weeks) in subjects with chronic post-surgical CME. If pegaptanib treatment is shown to be beneficial for this condition, additional studies could be performed to prove long-term effectiveness in patients with chronic CME or even for prophylaxis for patients known to be at high risk of developing CME following ocular surgery.