Current Options in Low Vision Rehabilitation

Samuel N. Markowitz, MD, FRCS(C), Associate Professor of Ophthalmology, Faculty of Medicine, University of Toronto; Director, Low Vision Rehabilitation Program, Department of Ophthalmology, University of Toronto; Staff, Toronto Western Hospital, University Health Network, Toronto, ON.

Low vision can result from loss of macular function, with loss of peripheral vision or from loss of hemi-fields of vision such as in cases with stroke. Low vision rehabilitation (LVR) is the continuation of care after all other means for restoration of vision were used and failed. Modern LVR is a multidisciplinary endeavour responsible for providing assessment, prescribing devices, and conducting training sessions for individuals with low vision. Ontario recognizes the diverse needs of individuals requiring LVR interventions, covers LVR assessments and LVR training sessions, and provides financial subsidies for the purchase of low vision devices.
Key words: low vision rehabilitation, low vision, age-related macular degeneration, assistive devices, vision therapy.

A Clinical Perspective of Diabetic Retinopathy

Chris Hudson, PhD, MCOptom, FAAO, Professor, School of Optometry, University of Waterloo, Waterloo, ON; Associate Professor, Department of Ophthalmology and Vision Sciences, University of Toronto, Toronto, ON; Director of Retinal Research, University Health Network, Toronto, ON; scientist, Toronto Western Research Institute, Toronto, ON.

Diabetic retinopathy (DR) remains the leading cause of vision loss and blindness in people of working age, in spite of the fact that current treatments are effective. Vision loss occurs in DR due to the development of maculopathy, especially diabetic macular edema, and due to proliferative diabetic retinopathy. Vision loss due to DR is preventable with the appropriate monitoring and timely treatment. Improved patient and health professional, education to encourage tight control of blood glucose and other systemic factors, and the establishment of readily available and appropriately timed eye examinations are necessary steps to further reduce visual impairment of people with diabetes.
Key words: diabetic retinopathy, vision loss, macular edema, neovascularization, laser photocoagulation.

The Evolution of Cataract Surgery: The Most Common Eye Procedure in Older Adults

Lorne Bellan, MD, Chairman, Department of Ophthalmology, University of Manitoba, Winnipeg, MB.

Cataract surgery is the most common refractive surgical procedure performed on aging individuals. Major advancements in surgical and lens technology have led to enormous increases in surgical volume because of the improved safety profile and outcomes. Current research holds the potential for restoring full vision, including accommodation, without the need for glasses in the near future.
Key words: cataract, lens, refractive, vision, phacoemulsification.

Age-Related Macular Degeneration: A Leading Cause of Blindness among Older Adults

Robert E. Coffee, MD, MPH, Clinical Instructor, Jules Stein Eye Institute, David Geffen School of Medicine, University of California, Los Angeles, USA.
Tara A. Young, MD, PhD, Assistant Professor, Jules Stein Eye Institute, David Geffen School
of Medicine, University of California, Los Angeles, USA.

Age-related macular degeneration (AMD) is the leading cause of blindness among older adults in North America. This article reviews the clinical spectrum, risk factors, pathophysiology, and potential therapeutic options for this disease. Despite significant advances in the treatment of certain forms of AMD, there is currently no cure for this degenerative condition. The substantial personal, social, and economic burden of AMD requires that those who provide care to older adults have a general understanding of this cause of blindness. It is important for the ophthalmologist and primary care physician to address modifiable risk factors for the progression of AMD such as poor cardiovascular status and smoking, which may worsen visual loss. In addition, educating patients and their families regarding risk factors and potential treatment options may greatly benefit those affected by AMD.
Key words: blindness, geriatric, age-related macular degeneration, choroidal neovascularization, ranibizumab, bevacizumab.

Preserving Our Vital Senses into Old Age

Our eyes and our ears are how we make sense of the world around us. While many people have been very successful despite visual or hearing impairments (and on occasion both), many of the compensatory abilities tend to decline with age. For example, as people age, more of their balance abilities depend on vision. Thus with increasing visual impairment, we get increased likelihood of falling. Even minor degrees of cognitive difficulty dramatically increase the impact of visual and hearing impairments. Simple tasks, such as injecting insulin, or taking the right pill at the proper time become very challenging with sensory impairment. Hearing-impaired older persons do not hear our instructions properly and often are too embarrassed to ask us to repeat, or do not even realize they have missed important information. Not surprisingly, both ophthalmologists and otorhinolaryngologists see large numbers of older patients. It is thus very important that at Geriatrics & Aging we provide a focus on aging eyes and ears.

Our continuing education article this month is “Age-Related Macular Degeneration: A Leading Cause of Blindness among Older Adults” by Dr. Robert Coffee and Dr. Tara Young. I am particularly interested in this article for two reasons. First, recent research has brought about a much greater understanding of the risk factors for the disorder, and second, one of the authors (Dr. Young) was a student of mine before starting a brilliant academic career in the United States.

When I started medical practice, cataract surgery was a crude affair, with patients using contact lenses (often difficult for an 80-year-old with tremor) or unsightly cataract glasses. Times have certainly changed as outlined in another of our focus articles, “The Evolution of Cataract Surgery: The Most Common Eye Procedure in the Older Adult” by Dr. Lorne Bellan. Our third eye-related article is also on a common theme, namely “A Clinical Perspective of Diabetic Retinopathy” by Dr. Chris Hudson. Our last focus article is on a problem that does not sound glamorous, but is extremely important to our patients, “Cerumen Impaction” by Dr. Mark A. Lutterbie and Dr. Daniel McCarter.

As expected, this issue also features articles on several important geriatric topics. Our cardiovascular disease column is on the “Approach to Dyspnea among Older Adults” by Dr. Siamak Moayedi and Dr. Mercedes Torres. Our gastrointestinal health column is entitled “Diagnosis and Management of Gastroesophageal Reflux Disease and Dyspepsia among Older Adults” and it is authored by Dr. Sander Veldhuyzen van Zanten. There is a tie-in with our focus article on diabetic retinopathy in the article by Dr. Medha Munshi and Dr. Alissa Segal entitled “Insulin Therapy for Older Adults with Diabetes.”

Finally, I recall a famous letter in the late 1970’s by David Marsden, a great neuroscientist and movement disorder specialist, calling for research to delineate the difference between Parkinson’s Disease Dementia and Alzheimer’s Disease (if in fact there was a difference). This challenge became even more complex when Dementia with Lewy Bodies was described as a discrete entity. Dr. Catherine Agbokou, Dr. Emmanuel Cognat, and Dr. Florian Ferreri address this last clinical dilemma in their article “Parkinson’s Disease Dementia versus Dementia with Lewy Bodies.”

Enjoy this month’s issue,
Barry Goldlist

Should Older People Be Regularly Screened for Vision and Hearing by Primary Health Care Providers?

Jie Jin Wang, MMed, PhD, Centre for Vision Research, Department of Ophthalmology, Westmead Millennium Institute, University of Sydney, Australia.
Jennifer L. Smith, BA, PhD, Australian Health Policy Institute, University of Sydney, Australia.
Stephen R. Leeder, BSc (Med), MB, PhD, Australian Health Policy Institute, University of Sydney, and The Menzies Centre for Public Health Policy, Australia.

Vision and hearing impairments are common in older people. They not only impact on the quality of life and independent living of affected individuals, but also contribute to the overall burden of aged care. Although current evidence supports screening for age-related vision and/or hearing impairments, good- quality evidence on the effectiveness of sensory interventions (e.g., treatment for eye conditions or rehabilitation for hearing loss) is lacking. Evidence from community-based randomized controlled trials is needed before implementing community-wide screening. Case-finding during primary health care can be considered. Strategies to reduce the overall burden from common disabilities, including sensory impairments, among older people are keys to achieving the goal of “aging well, aging productively.”
Key words: aging, screening, vision, hearing, sensory impairment.

Medical Management of Glaucoma: Clinical and Research Update

Elliott M. Kanner, MD, PhD, Department of Ophthalmology, Edward S. Harkness Eye Institute, Columbia University College of Physicians and Surgeons, New York, NY, USA.
James C. Tsai, MD, Associate Professor and Director, Glaucoma Division, Department of Ophthalmology, Edward S. Harkness Eye Institute, Columbia University College of Physicians and Surgeons, New York, NY, USA.

Glaucoma is a sight-threatening, progressive optic neuropathy whose incidence increases with age. Currently, the only proven treatment for glaucoma is the reduction of intraocular pressure (IOP). As medical treatment has become safer and diagnostic modalities have become more sensitive, it has become possible to detect and treat glaucoma earlier. This means that with more aggressive screening and treatment, a common cause of irreversible blindness can be prevented. As more patients are treated earlier, it is important not only for ophthalmologists but also for primary care physicians to be aware of the barriers to adherence and possible interactions and side effects of glaucoma medications. Parallels between glaucoma and other neurodegenerative disease are stimulating new approaches to therapy beyond IOP control, targeted directly at the prevention of axonal loss.
Key words: glaucoma, intraocular pressure, medications, neuroprotection, retinal ganglion cell.

Latest Treatment Options in Age-Related Macular Degeneration

Sohel Somani, MD, FRCSC, Clinical Instructor, Department of Ophthalmology and Vision Sciences, University of Toronto; Associate Staff, Princess Margaret Hospital, Toronto, ON.

Age-related macular degeneration (ARMD) is a progressive disease affecting the central vision of patients older than 55 years. ARMD is classified as atrophic (dry) or exudative (wet) forms based on clinical characteristics. Management of atrophic ARMD includes vitamin supplementation with high-dose antioxidants in appropriate patients. Patients who develop exudative ARMD may be eligible for treatment depending on flourescein angiogram characteristics. Options available to close a choroidal neovascular membrane include thermal laser photocoagulation or photodynamic therapy. Other treatment modalities are currently under investigation that may lead to more therapeutic options in the future.

Key words: macular degeneration, vitamins, laser, photodynamic therapy, angiogenesis.

Classification of Age-Related Macular Degeneration vs. Age-Related Maculopathy

Classification of Age-Related Macular Degeneration vs. Age-Related Maculopathy

Dear Editor,
In the article "Age-Related Macular Degeneration: An Update on Nutritional Supplementation" (May 2003, Vol. 6, No. 5), the classification of macular degeneration stages may not be entirely accurate--at least it deviates from what is now accepted as standard classification in the major clinical trials. There is consensus that soft drusen represent age-related maculopathy, not macular degeneration. Geographic atrophy characterizes dry macular degeneration, while choroidal neovascular membranes and disciform scar characterize wet macular degeneration.

Sandeep Jain, MD
Instructor in Ophthalmology,
Harvard Medical School, Boston, MA, USA

Dr. Sohel Somani, author of the article "Age-Related Macular Degeneration: An Update on Nutritional Supplementation", responds:
I appreciate the opportunity to respond to Dr. Sandeep Jain's comments on the classification scheme of Age-Related Macular Degeneration (ARMD). While most would agree that geographic atrophy represents late dry ARMD, there is no clear consensus in the literature on how to classify drusen and retinal pigment epithelial changes. Some studies classify them as a mild to moderate dry macular degeneration, while others classify them as age-related maculopathy.

The classification scheme used in the Geriatrics & Aging article is similar to that used by The Age-Related Eye Disease Study Group (AREDS).¹ Namely, this group classified ARMD into four levels depending on the type and extent of drusen, as well as the presence of geographic atrophy and neovascular changes. In this scheme, small soft drusen, in the absence of geographic atrophy, would be classified as Level 1 ARMD. In contrast, other studies would call these changes early age-related maculopathy.²

Hopefully, the differing terminology that may be encountered in various articles to describe early age-related macular pathology (i.e., degeneration vs. maculopathy) does not detract from the underlying point of the article; namely, to consider vitamin supplementation in those patients who meet the AREDS criteria.

Sohel Somani, MD
Medical Retina Fellow,
University of Toronto, Toronto, ON.

References

1. The Age-Related Eye Disease Study Research Group. The Age-Related Eye Disease Study system for classifying age-related macular degeneration from stereoscopic color fundus photographs: the Age-Related Eye Disease Study Report Number 6. Am J Ophthalmol 2001;132:668-81.
2. Bird AC, Bressler NM, Bressler SB, et al. An international classification and grading system for age-related maculopathy and age-related macular degeneration. Surv Ophthalmol 1995;39:367-74.

Dear Editor,
The article "The Management of Tinnitus" (June 2003, Vol. 6, No. 6) did not mention that one possible cause of tinnitus may be a vitamin B12 deficiency.¹ Given that B12 deficiency is thought to affect up to 12% of older people,² a therapeutic trial of vitamin B12 may be worthwhile even when the serum B12 level is not clearly subnormal, as more definitive tests of B12 deficiency, such as homocysteine or methylmalonic acid, are not always available.

Henry Olders, MD, FRCPC (Psychiatry),
Assistant Professor,
Faculty of Medicine, McGill University
Associate Psychiatrist,
SMBD-Jewish General Hospital, Montreal, QC.

References

1. Shemesh Z, Attias J, Ornan M, et al. Vitamin B12 deficiency in patients with chronic-tinnitus and noise-induced hearing loss. Am J Otolaryngol 1993;14:94-9.
2. Lindenbaum J, Rosenberg IH, Wilson PW, et al. Prevalence of cobalamin deficiency in the Framingham elderly population. Am J Clin Nutr 1994;60:2-11.

Dr. John P. Preece, co-author of the article "The Management of Tinnitus", provides the following response:
We thank Dr. Olders for bringing up the possible relation between vitamin B12 deficiency and tinnitus. Vitamin B12 deficiency has been implicated in a number of neurological deficits, including tinnitus.^1,2 Since, as Dr. Olders notes, vitamin B12 deficiency is common in the older population, this link deserves further examination. Since none of us are physicians, we take no position on the value of a therapeutic trial with vitamin B12.

John P. Preece, PhD,
Associate Professor,
Communicative Disorders,
University of Rhode Island Kingston, RI, USA
Signed for co-authors R.S. Tyler, PhD and W. Noble, PhD

References

1. Dharmarajan TS, Adiga GU, Norkus WP. Vitamin B12 deficiency. Recognizing subtle symptoms in older adults. Geriatrics 2003;58:30-4;37-8.
2. Scherer K. Images in clinical medicine. Neurologic manifestations of vitamin B12 deficiency. N Engl J Med 2003;348:2208.

Dear Editor,
A host of electromagnetic stimulation therapies that goes back over 200 years was not mentioned in the article "The Management of Tinnitus" (June 2003, Vol. 6, No. 6). In recent years, cranio-electrical stimulation has proved successful in some types of tinnitus. Most recently, rTMS (repetitive transcranial magnetic stimulation), which has been very successful in drug-resistant depression, has shown potential. Admittedly, it is difficult to rule out a placebo effect and one has to be wary of spurious devices and extravagant claims. A thorough review of these techniques may be found in the forthcoming book Bioelectromagnetic Medicine, to be published by Marcel Dekker, Inc. later this year (http://www.dekker.com/servlet/product/productid/4700-3).

Paul J. Rosch, MD,
Clinical Professor of Medicine and Psychiatry,
New York Medical College, New York,
President of The American Institute of Stress,
Yonkers, NY, USA

Drs. Preece, Tyler and Noble reply:
The length constraints of the journal kept us from being truly comprehensive in our review of tinnitus. Dr. Rosch correctly reminds us that there have been many attempts at electromagnetic stimulation therapy over the years. We agree that rTMS appears to be a promising approach, at least for a subset of tinnitus sufferers. We look forward to the book that he mentioned. Plewnia, et al. have published a controlled clinical trial with 14 patients that showed significant results.¹

John P. Preece, PhD
Richard S. Tyler, PhD,
Professor, Speech Pathology and
Audiology and Otolaryngology,
Head and Neck Surgery, University of Iowa, Iowa City, IA, USA

William Noble, PhD,
Professor, Psychology,
University of New England, NSW, Australia

Reference

1. Plewnia C, Bartels M, Gerloff, C. Transient suppression of tinnitus by transcranial magnetic stimulation. Ann Neurol 2003;53:263-6.