Anatomical and functional results in 38 eyes with retinal detachment and major proliferative vitreoretinopathy (C3, D1, D2) treated by more or less wide retinotomy or circular retinectomy; 50% of the retinae have reattached, with an improvement of the visual function in 12 cases out of 21. The best procedure in these cases seems to be a retinotomy of at least 180 degrees on an eye filled with silicone oil to prevent secondary retractions. Circular retinectomy has been given up for retinotomy.