Therefore, treatment is required every three months for an unknown period of time. In other words, it is not a cure . Plasmapheresis involves about twenty expensive sessions of blood exchange, supposedly removing some unknown substance damaging to the macula. There is no scientifically proven benefit, or even a reason why it should work. This procedure, developed in 1991, also requires a surgical procedure called a vitrectomy.
Some patients become totally blind after surgery.
At Charles Retina Institute we stopped performing this procedure in 1994, because the potential benefits do not justify the risk, in our view. But subsequently, many more statistically correct studies showed that interferon had no beneficial effect. Again, initial studies seemed to indicate that new vessels decreased after treatment. But subsequently, several statistically correct studies proved that thalidomide had no beneficial effect. One large study is still underway.