Book Review

Age-Related Macular Degeneration

N Engl J Med 1999; 340:1297-1298April 22, 1999

Article

Age-Related Macular Degeneration
Edited by Jeffrey W. Berger, Stuart L. Fine, and Maureen G. Maguire. 463 pp., illustrated. St. Louis, Mosby, 1999. $175. ISBN: 0-323-00200-5

A multitude of disorders and diseases become more prevalent with age. Some are inconvenient, some are life-threatening, and some impair our ability to remain independent, such as those associated with blindness or visual impairment. Visual loss due to age-related macular degeneration is the most common cause of blindness in patients over the age of 50 years. Age-related macular degeneration appears in two general forms. The dry, or nonexudative, form is characterized by yellow deposits called drusen and by atrophy of the retinal pigment epithelium, whereas the exudative form is typically due to the growth of new blood vessels (neovascularization) beneath the sensory retina. Conventional treatment with laser photocoagulation to destroy the neovascular complex can be of some benefit, but recurrences and a progressive loss of central vision are common nevertheless.

Blindness has a severe impact on the elderly, and considerable resources are directed toward preventing and treating macular degeneration. Although major breakthroughs in the management of the disease remain elusive, several important milestones have been reached, and the prognosis for those with age-related macular degeneration is likely to improve over the next decade.

Age-Related Macular Degeneration, a comprehensive book, emphasizes the interdisciplinary, cooperative approach now being taken to the understanding of this disease. Its 27 chapters can be roughly divided into four major categories. The first several chapters are introductory and provide a background for an understanding of age-related macular degeneration. They describe normal macular physiology, the natural history of macular degeneration, its epidemiology and genetics, and the part that nutrition plays in its development. The second group of chapters deals with current methods of diagnosis of the disease and the pathophysiology of its different forms. The third section details current strategies used to treat age-related macular degeneration, including laser photocoagulation and surgery. The final chapters concern visual rehabilitation.

The introductory chapters are comprehensive and informative. However, the chapter entitled “Geographic Atrophy,” an important form of late age-related macular degeneration, would be better placed within the chapter on natural history or directly thereafter. Although the chapter on nutrition carefully details the effects that antioxidant vitamins, zinc, and other nutrients might have on the disease, on the basis of scientific evidence, some widely used supplements, which are enthusiastically used by the lay population, are not mentioned.

One of the most remarkable chapters, entitled “Histopathologic Features,” is in the second section of this book. This stunningly illustrated 74-page chapter presents many unique and important clinicopathological correlations with use of fundus photographs of eyes with macular degeneration along with unsurpassed histopathological sections. Anyone desiring a thorough understanding of the pathology of age-related macular degeneration from the current perspective must read this chapter.

The section on therapeutic approaches introduces the possible role of prophylactic laser treatment for macular degeneration. Conventional laser therapy for the treatment of choroidal neovascularization and the potentially exciting role that intravenously injected photosensitizing compounds might have in improving the results of laser treatment are well detailed.

Pharmacologic therapy for macular diseases, including macular degeneration and diabetic retinopathy, will undoubtedly become more important in the future. A brief but cogent chapter outlines the work completed to date on drugs that inhibit angiogenesis (neovascularization) as a treatment for age-related macular degeneration. Current surgical approaches to treatment are explained well. The attendant risks of such specialized surgery are also presented here fairly, in contrast to typical news releases, which suggest to the public that such surgery is routine and has broad indications. Transplantation of retinal pigment epithelium and photoreceptors and gene therapy may someday prove to be central in the treatment of age-related macular degeneration, and the chapters on these topics are particularly intriguing and authoritative.

The use of a photodiode-based retinal prosthesis to mimic the function of the retina is an exciting avenue of investigation that relies on advances in microcircuitry and microchip technology. Such prostheses might provide some semblance of vision for those who have severe visual impairment; they are described in a separate chapter. To date, however, the prosthetic retina remains a strictly experimental device that has been used in only a handful of patients.

Patients with end-stage age-related macular degeneration often feel abandoned, defeated, and depressed, yet rehabilitative programs are available that, in many cases, remarkably improve their ability to function. Innovative forms of technology continue to be applied to assist patients with macular degeneration with the tasks of daily living. The final chapters of Age-Related Macular Degeneration educate the reader in this crucial but often neglected area.

In summary, this book is an important reference for clinicians, researchers, and members of the scientific community. Lay readers will undoubtedly improve their understanding of age-related macular degeneration, although some increasingly popular yet scientifically unproved treatments are not discussed. They deserve mention, since several of the chapters discuss controversial topics, including those on radiation therapy and a hemodynamic model of pathogenesis. A separate chapter encompassing alternative therapies would make the book more complete and might serve to expand its target audience. On balance, however, the shortcomings of this book are minor. Age-Related Macular Degeneration clearly represents a substantial scientific achievement; the fact that it is moderately priced considering its content will ensure its success.

Thomas R. Friberg, M.D.
Eye and Ear Institute, Pittsburgh, PA 15213