3 The procedure
3.1 The aim of an implantable miniature lens system is either to magnify the image on the macula, or to optically move the image onto an undamaged part of the retina. Implantation of lens systems for advanced age-related macular degeneration (AMD) is usually done under local anaesthesia. The natural lens of the eye is removed through a small incision at the limbus (the area where the cornea meets the sclera) and the new lens system is inserted. Artificial lens systems consist of either a miniature telescope prosthesis implanted in the capsular bag of the natural lens, or of 2 separate lenses with 1 lens implanted in front of and 1 lens implanted behind the iris.
3.2 The technique for implantation varies according to the system being used. Generally, if a telescope prosthesis is used, a larger limbal incision may be needed. Viscoelastic fluid is used during implantation to facilitate insertion and is then removed by irrigation or aspiration. When a single miniature telescope prosthesis is used, images are magnified by the implanted lens system and focused on the macula. When a system of 2 separate lenses is used, the lenses are rotationally aligned to deflect a magnified image away from the most damaged part of the macular and towards a less damaged area. In both cases, the contralateral eye is used for peripheral vision. After implantation, patients need visual rehabilitation.