penetrating keratoplasty an alternative to − − Deep lamellar keratoplasty

become their better seeing eye. The growing literature on the management of HIV related retinal detachment provides other useful insights into the disease process and also the surgical use of silicone oil. Published series have varied in their reported incidence of proliferative vitreoretinopathy. 5 6 8–11 There is, however, a consensus that epiretinal membrane formation does occur in these cases and a high incidence has been observed in some series. 9 This is notable in relation to the pathogenesis of proliferative vitreoretinopathy since T lymphocytes have been observed in the periretinal proliferation in this condition and it has been suggested that they may play a role in its progression. 20 It would appear, at least in the setting of an inflammatory viral retinitis, that despite profoundly abnormal T cell function (in particular CD4+ T cells, known to be involved in fibrogenesis and wound healing) there remains a fibrogenic stimulus suYcient to result in epiretinal membrane formation. The initial impression of a low incidence of cataract formation in HIV related retinal detachment eyes treated with silicone oil was attributed to the protective eVect of an intact anterior hyaloid face and the lack of multiple interventions. It is clear, however, from the current study by Irvine and colleagues and other recent series, 18 that with relatively longer survival of patients undergoing surgery progressive cataract formation does occur in many eyes and may be visually significant. The incidence of corneal opacification, raised intraocular pressure, hypotony, and oil emulsification appears to be low. Several issues remain unresolved in the management of AIDS patients with necrotising retinitis and retinal detachment. The role of laser photocoagulation at the time of surgery is still uncertain and the possible role of inferior retinectomy in eyes with significant epiretinal membrane formation may also justify investigation. Late cataract extraction and silicone oil removal must also be considered in a minority of patients. Advances in antiviral chemotherapy and the availability of drug delivery by intraocular depot systems provide hope of treating the late visual loss in AIDS patients with necrotising retinitis although the interaction of such treatments with intraocular silicone oil is as yet unknown.