Ophthalmologists and neurologists consider strengthening their bonds

Collaborative efforts between these two specialties may have significant benefits for patients suffering from ocular or neurological diseases.

Gordon T. Plant

There should be a focus on reunifying the fields of neurology and ophthalmology in an effort to enhance patient outcomes, according to a physician.

“I would like ophthalmologists and neurologists to go away from the lecture realizing the close relationship between their two specialties in patient care,” Gordon T. Plant, MD, FRCP, FRCOphth, who presented the Edmund B. Spaeth Oration in Philadelphia earlier this year, told Ocular Surgery News.

“The number of people who are bilingual in the two fields has fallen proportionately. … There are more ophthalmologists who are ignorant of neurology and more neurologists who are ignorant of ophthalmology than there were 20 years ago,” Dr. Plant said.

Emphasizing the eye’s status as an extension of the brain, he encouraged ophthalmologists who are currently studying diseases such as glaucoma to speak with neurologists about recent advances in their field and vice versa. In addition, he stressed the need for more neuro-ophthalmologists who are knowledgeable in both disciplines.

Dr. Plant highlighted the importance of a stronger neuro-ophthalmic presence by discussing retinal complications caused by the drug Sabril (vigabatrin, Lundbeck); used to treat epilepsy, vigabatrin may damage nerve fibers in the retina and potentially cause vision loss, complications that did not come to light during the drug’s evaluation, he said.

Two-way degenerative processes

There is a two-way relationship between the eye and brain, and study findings demonstrate that degeneration may be observed traveling in both directions, Dr. Plant said.

Recent findings detail abnormal brain function in glaucoma patients, and complications in the optic nerve and retina are being found in neurologically damaging diseases such as Alzheimer’s.

“When one part of the nervous system is damaged, there are degenerative processes that are transmitted to other parts. This is because nerve cells depend upon their contact with other nerve cells to remain healthy,” Dr. Plant said.

Dr. Plant’s research focuses on trans-synaptic retrograde degeneration from occipital damage after stroke. In trans-synaptic anterograde degeneration, neurons are deprived of input from destroyed axons and subsequently atrophy; in retrograde degeneration, neurons that have lost recipient axons for their output also atrophy.

Dr. Plant said that if the optic radiations are damaged, degeneration may transmit toward the visual cortex as well as toward the optic nerve.

Dr. Plant posited questions for neuro-ophthalmologists, neurologists and ophthalmologists to collectively consider: “Is glaucoma a neuro-degeneration or an optic neuropathy with secondary changes in the brain? Are the retinal changes in Alzheimer’s, Parkinson’s and multiple sclerosis secondary, or is the retina involved in the primary processes?”

Neuro-degeneration tends to happen quickly, within the first few months or first year of disease onset. Dr. Plant is interested in whether preventing neuro-degeneration would, in fact, enhance visual outcomes.

OCT and future research

In addition to the effects of occipital damage, Dr. Plant also studies familial amyloidoses, rare types of Alzheimer’s disease that affect vision, optic neuritis and multiple sclerosis, all in the context of neuro-degenerative processes.

He said he is particularly enthusiastic about research being conducted on multiple sclerosis, which involves using the retina as a tool to monitor the disease’s effects.

“Optical coherence tomography allows us to study the tissues of the eye by a simple and noninvasive technique which cannot be applied elsewhere in the brain,” he said.

Dr. Plant stressed the significance of using OCT to study the visual effects of neurological diseases such as multiple sclerosis and Alzheimer’s, saying that such breakthroughs would not be possible without the collaborative efforts of neurology and ophthalmology.

“All of these discoveries are only being made because ophthalmology exists within the neurosciences and because neurologists and neuroscientists are interested in the eye,” he told colleagues. “We are not going to do our best for patients unless we have people … who are bilingual and speak the grand language.” – by Michelle Pagnani

• Gordon T. Plant, MD, FRCP, FRCOphth, can be reached at Box 93, The National Hospital for Neurology and Neurosurgery, Queen Square, London, WC1N 3BG UK; 44-2073928956; email: gordon@plant.globalnet.co.uk.
• Disclosure: Dr. Plant has no direct financial interest in the products discussed in this article, nor is he a paid consultant for any companies mentioned.