Despite advances in the understanding of retinal biology, and in microsurgical technique and instrumentation, rhegmatogenous retinal detachment (RD) remains a condition that results in loss of visual function in the majority of affected eyes. This issue of Acta includes three papers on rhegmatogenous RD (Abouzeid & Wolfensberger 2006; Boberg-Ans et al. 2006; Saw et al. 2006).
Given the increasing use of cataract surgery, the issue of pseudophakic RD (and other serious complications such as endophthalmitis) is as important as ever. Although it may appear to the modern phacoemulsification surgeon that the risk of pseudophakic RD has decreased to insignificant levels, a large proportion of RD cases seen at vitreoretinal centres are indeed still pseudophakic (Ducournau & Le Rouic 2004). The paper by Boberg-Ans et al. (2006) presented in this issue of the journal provides some hard data concerning the longterm incidence of pseudophakic RD after modern, standardized phacoemulsificaton surgery. This register-based study found that the risk of RD in an eye operated for cataract was elevated for at least 6 years postoperatively, during which time the cumulated number of observed RD cases was more than nine times that of the cumulative background incidence (Boberg-Ans et al. 2006). The study utilized the unique Danish Patient Registry, which allowed complete follow-up of the end-point: surgery for RD at a hospital within Denmark. It confirms previous results for extracapsular cataract surgery in Denmark and elsewhere (Norregaard et al. 1996), and highlights the fact that pseudophakic RD continues to be a problem, even in the era of phacoemulsification surgery.
Surgery is indicated in the vast majority of RD cases and should be carried out by ophthalmologists who subspecialize in vitreoretinal surgery (Thompson et al. 2002). Between a third and half of RD cases present with the fovea still attached (Algvere et al. 1999). These ‘macula-on’ cases are traditionally considered to be ophthalmological emergencies because the visual prognosis is best if surgery is performed before the fovea detaches (American Academy of Ophthalmology 1996). Recently, a British study found that progression of subretinal fluid towards the foveal centre was observed in only 13% of macula-on RD cases during the time interval (usually of a few days) between presentation and surgery. In 4% (3/82) of these cases, progression included foveal detachment. Disappointingly, no risk factors for progression could be identified, so although we know that rapid progression to foveal detachment only affects a minority of macula-on RD patients, we cannot identify this minority a priori (Ho et al. 2005). As urgent surgery outside office hours is costly, and only necessary in a minority of macula-on RD cases, it remains a challenge to identify that minority. A further challenge involves increasing awareness of RD in the population so that a larger proportion of RD cases can be diagnosed before foveal detachment occurs.
Management of RD cases in which the fovea is already detached at presentation is the subject of a review paper in this issue of Acta (Abouzeid & Wolfensberger 2006). In these cases urgent surgery is rarely indicated, and the authors conclude that although surgery is best performed early rather than late, it can be deferred for up to a week after foveal detachment has occurred (Abouzeid & Wolfensberger 2006). The review also discusses the possibility of pharmacological intervention in order to improve the survival and function of foveal photoreceptors after macula-off RD (Abouzeid & Wolfensberger 2006).
Treatment options for RD are the subject of another review paper in this issue (Saw et al. 2006). There are currently three major methods in use for primary repair of uncomplicated RD: scleral buckling surgery, pneumatic retinopexy and pars plana vitrectomy with gas (or oil) tamponade. The paper by Saw et al. (2006) is a systematic review of the literature concerning these three methods, as well as the issue of drainage of subretinal fluid in scleral buckling surgery. The review concludes that pneumatic retinopexy may be performed for uncomplicated RD with retinal breaks within one clock hour of the superior two-thirds of the retina. The indication for primary vitrectomy is ‘evolving’, but the procedure is especially recommended when there is poor visualization of the retina. However, the authors conclude by stating that there is currently no preferred single method of treatment, and that we as surgeons should chose the technique we have the most experience with. Although this is undoubtedly true, I think that pneumatic retinopexy or primary vitrectomy in uncomplicated RD cases should be recommended only with the caveat that vitrectomy and/or intraocular gas in a phakic eye entails a high risk of subsequent cataract development (Tornambe et al. 1991). While subsequent cataract surgery may not seem too frightening, it should be remembered that in a young person it will result in the loss of accommodation in the affected eye. Furthermore, the risk of new retinal breaks and/or recurrent RD might be elevated after cataract surgery in these eyes (Grand 2003). The data presented by Boberg-Ans et al. (2006) in this issue of the journal underscore the fact that retinal complications from cataract surgery may occur several years after the operation. Hence, a fair comparison between scleral buckling surgery (without the use of intraocular gas) and pneumatic retinopexy or primary vitrectomy in phakic eyes requires lengthy follow-up. At least for phakic eyes with RD treated with primary vitrectomy, the results can, in my opinion, only be meaningfully assessed only after these eyes have undergone the inevitable cataract operation.