lower part of the eyeball impractical. This procedure is always combined with cryopexy or laser photocoagulation. The one operation reattachment rate may be slightly lower with pneumatic retinopexy but in spite of this, the final visual acuity may be better. Vitrectomy Vitrectomy is an increasingly used treatment for retinal detachment. It involves the removal of the vitreous gel and is usually combined with filling the eye with either a gas bubble (SF6 or C3F8 gas) or silicone oil. Advantages of using gas in this operation is that there is no myopic shift after the operation and gas is absorbed within a few weeks. Silicone oil is almost always removed after a period of 2–8 months depending on surgeon's preference. Silicone oil is more commonly used in cases associated with proliferative vitreo-retinopathy (PVR). Silicone oil may be light or heavy depending on the position of the breaks requiring tamponade. A disadvantage is that a vitrectomy always leads to more rapid progression of a cataract in the operated eye. In many places vitrectomy is the most commonly performed operation for the treatment of retinal detachment. Results of surgery 85 percent of cases will be successfully treated with one operation with the remaining 15 percent requiring 2 or more operations. After treatment patients gradually regain their vision over a period of a few weeks, although the visual acuity may not be as good as it was prior to the detachment, particularly if the macula was involved in the area of the detachment. However, if left untreated, total blindness will occur in a matter of weeks. Prevention Retinal detachment can sometimes be prevented. The most effective means is by educating people to seek ophthalmic medical attention if they have symptoms suggestive of a posterior vitreous detachment. Early examination allows detection of retinal tears which can be treated with laser or cryotherapy. This reduces the risk of retinal detachment in those who have tears from around 1:3 to 1:20. There are some known risk factors for retinal detachment. There are also many activities which at one time or another have been forbidden to those at risk of retinal detachment, with varying degrees of evidence supporting the restrictions. Cataract surgery is a major cause, and can result in detachment even a long time after the operation. The risk is increased if there are complications during cataract surgery, but remains even in apparently uncomplicated surgery. The increasing