JUL 16, 2008
By Nancy M. Holekamp, MD
Retina/Vitreous
Many retina specialists have adopted same-day combination therapy of Avastin injection followed by panretinal photocoagulation (PRP) laser surgery as the new standard of care for treating neovascular glaucoma (NVG). The current study provides data suggesting that this approach may be superior to treatment with PRP alone.
Eleven patients who received the combination treatment and 12 treated with PRP alone at one medical center between September 2004 and June 2007 served as subjects in the study, which had a retrospective consecutive case-control design. The combination therapy patients experienced a more rapid decrease in IOP. The frequency and rate of neovascular regression was also greater in the combined treatment group.
Despite the apparent increased success seen in this small study when treating NVG using combined Avastin-PRP therapy, there are several caveats to the results. First, intravitreal Avastin may mask the full ischemic drive and fool retina specialists into undertreating with PRP. In fact, the study's researchers found that the mean number of laser spots in the combined treatment group was less than in the PRP only group, and two of 11 patients in the combination group had recurrent neovascularization of the iris (NVI). Second, PRP is the only proven long-term treatment for retinal ischemia leading to NVI or NVG.
Avastin should be considered a useful, initial, adjunctive treatment for temporary control of retinal ischemia until sufficient PRP can be administered. Treatment with PRP is still a necessary part of the standard of care.
Financial Disclosures
Dr. Holekamp is a consultant to Alcon Laboratories, Inc., and Genentech, Inc., and receives lecture fees from Genentech.