What will be new at the back of the eye in the year 2020?
The World Ophthalmology Congress was held from February 19-24, 2006 in Brazil. I took the opportunity to ask some leading experts how they think the diagnosis and management of posterior segment conditions might be different in the future, specifically in the year 2020. What follows is a summary of their views, which we hope will generate interest and lively discussion amongst our readers and their colleagues.
Dr Alexander Brucker, Professor of Ophthalmology at the University of Pennsylvania and Editor of the journal Retina, suggests that by the year 2020, decisions about treatment will be based on diagnosis using high definition optical coherence tomography (OCT) visualisation of the retina, in conjunction with fluorescein angiography (FA). Although the interpretation of the clinical findings may be similar, management will be more pharmacologically directed. He anticipates change will also be effected through alteration of the patient’s individual risk factor profile. For proliferative disease, the treatment will probably continue to be with panretinal laser photocoagulation, but the addition of new pharmacologic agents (e.g. anti-Vascular Endothelial Growth Factor or anti-VEGF) could reduce the requirement for this destructive treatment.
According to Dr Alistair Laidlaw, Consultant Vitreoretinal Specialist at St Thomas’ Hospital, London, UK, the prevention of diabetic retinopathy through effective screening will take priority. He foresees an increased use of non-mydriatic, wide-field, low-light systems, which will make screening comfortable and effective. Management will be through improved medical care of diabetes overall, and use of newer agents (e.g. protein kinase C inhibitors) as well as further developments in nondestructive laser systems.
Retinopathy of prematurity (ROP)
Dr Rajvardhan Azad, Professor of Ophthalmology and Head of Vitreo-Retinal and ROP unit at the Dr R.P. Centre for Ophthalmic Sciences, New Delhi, predicts that by 2020, there will be increased awareness of the condition amongst ophthalmologists and neonatologists through better, easier and more costeffective imaging of the retina (e.g. RetCam).
These imaging systems will also improve diagnosis and therefore subsequent management. Therapies will include increased use of angiostatic agents, and more focal, less destructive laser treatments. The current belief that surgical techniques do not work will change as advances in techniques develop (e.g. use of plasminogen to liquefy the vitreous to reduce the traction). Dr Clare Gilbert, Reader in International Eye Health at the London School of Hygiene and Tropical Medicine, believes that clinical trials currently underway (e.g. optimum oxygen concentrations for premature babies) will help to reduce the incidence of sight-threatening disease. Until now, detection of ROP has been performed by ophthalmologists using indirect ophthalmoscopy, but in the future digital imagery (taken by nonophthalmologists) with automated image analysis, or remote (telemedicine) expert reading, will offer the possibility of screening in the true sense of the word. Regarding management, she believes that, as with other vasoproliferative eye conditions, there will be medical treatments that block the disease from progressing. The current use of ablation techniques will be kept to a minimum.
Dr Carol Shields, Professor of Ophthalmology and Co-Director of the Oncology Service at the Wills Eye Hospital, Philadelphia, foresees earlier detection of cases through increased awareness (e.g routine screening of the red reflex) which will potentially identify the sporadic cases. A change in chemotherapy treatment from systemic to local delivery will reduce overall side-effects. New developments in slow-release mechanisms (e.g. a reservoir system inserted into the sub-Tenon space which can then be regularly filled with chemotherapeutic agent) and increased use of adjunctive treatments (e.g locally placed anti-proliferative agents like combretastatin), will further improve treatment success.
Dr Alejandra A. Valenzuela of the Royal Children’s Hospital, University of Queensland, Australia, considers that by 2020, better education and increased surveillance by the health community will be fundamental to earlier diagnosis and sucessful outcomes. Multimodal therapeutic advances will save not only the life of the patient, but also preserve the eye and, in some cases, preserve the vision. The addition of gene therapy to the particular Rb1 mutation affecting some children may provide a further avenue in management.
Dr Yasuo Tano, Professor of Ophthalmology, University of Osaka, President of Asia- Pacific Academy of Ophthalmology, envisages that pars plana vitrectomy (PPV) will take over as the primary choice for detachment repair. Improved imaging with 3-dimensional OCT high resolution imaging will improve visualisation of the posterior segment. Non-vitrectomising macular surgery may offer the hope of non-accelerated progression of nuclear cataract that currently occurs following PPV. Bimanual techniques for surgery are also likely to be more widespread.
Dr G W Aylward, Medical Director at Moorfields Eye Hospital, London, foresees no significant change in the diagnostic and management techniques for routine retinal detachments, as reattachment rates currently reach 90 per cent. He suggests that the main thrust by the year 2020 will be focused at the public health level, such as alerting the public to early symptoms and signs in order to ‘catch’ detachments before the macula is affected.
Dr Borja Corcostegui, President of Española de Retina y Vítreo (SERV) and Director of Instituto de Microcirugía Ocular (IMO), Barcelona, added that, as the posterior segment diseases are better understood (particularly the vascular disorders), the range of conditions that require surgery and indications for intervention would be quite different in 2020.
Age-related macular degeneration (AMD)
Dr. Rosario Brancato, Professor of Ophthalmology, University San Raffaele, Milan, Italy and Editor of the European Journal of Ophthalmology, predicts that diagnosis for AMD will be directed at three levels:
- Understanding pathological angiogenic mechanisms
- Understanding these effects in the local tissue
- Epidemiological and genetic research regarding predispositions to AMD.
FA, Indocyanine Green (ICG) angiography and OCT will continue to prove useful for diagnosis and monitoring evolution of the disease. Treatments will be directed by the diagnosis and will specifically target the pathogenic mechanisms. In this regard, finding an effective drug for the prevention and the regression of pathological neovascularisation will be important. Research and development into regenerative therapies will also increase in importance. An important challenge will also be to identify the best delivery systems for these medications (e.g. oral, subconjunctival, even topical).
Retinal dystrophies, e.g. retinitis pigmentosa
Dr Ian Constable, Professor of Ophthalmology, University of Western Australia and Director of Lions Eye Institute, Perth, believes that by the year 2020, the range of specific gene defects will have been documented for the various clinical phenotypes. Gene function (e.g. enzymatic, cell signaling) for most dystrophies will also be understood, and animal models in place. Gene therapies will predominantly be available for large families or populations, however there will be some scope for developing customised treatments. In general, the strategy will be:
- Autosomal recessive – replace the defunct gene
- Autosomal dominant – insert a separate gene.
Dr Richard Gisbert, Professor of Ophthalmology, University of Hamburg and co-founder of the European Society of Retinal Specialists (EURETINA), foresees potential treatment options for retinal dystrophies in the future to include cell replacement strategies (i.e. transplantation of stem cells, progenitor cells, primary retinal cells or retinal tissue), gene therapy, and, for advanced cases, electronic retinal prostheses