July 1, 2003
D M Pizzi
Real Living with Multiple Sclerosis
ABNORMAL EYE MOVEMENTS have long been considered a symptom of MS and are often considered in its diagnosis. Moreover, previous research questioned whether a link existed between the rate of disease progression and eye abnormalities in persons with MS.
Now, new research poses an interesting theory: Abnormal eye movements may be a predictor for disability in individuals with MS. The significance of this potential finding is that thorough eye examinations may be a useful method for predicting clinical disability in MS.
Joy Derwenskus, DO, a third-year neurology resident at Case Western Reserve University, Cleveland, Ohio, led the study. Fifty MS patients underwent systematic neuro-ophthalmologic exam-nations for 2 years. She stressed at the recent 2003 annual meeting of the American Academy of Neurology that her intent was to find a sensitive predictor of MS disease severity in the hopes that individuals at heightened risk of disability could be identified early.
The researchers utilized a point system designed by R. John Leigh, MD, professor of neurology at the Veterans Administration Medical Center at case Western Reserve University, to quantitate the examination findings. A score over 2 on this scale would classify an individual as having abnormal eye movements.
Twenty-two of the 50 (44%) patients had abnormal eye exam results at the start of the study. According to Dr. Derwenskus, there were no significant demographic differences (age, years of having MS) between those who tested normal at the beginning of the study and those with abnormal eye movements.
Dr. Derwenkus and her colleagues were able to follow up with 40 of the initial study participants after 2 years. The age range for those individuals was 28 to 74 years; participants had been living with diagnosed MS for as little as 19 months to as long as 38 months. Fifteen patients were described as having relapsing-remitting MS, 13 were diagnosed with secondary progressive MS, six had primary progressive MS, and six were diagnosed with relapsing-progressive MS.
Seventy percent of the patients had experienced a progression of their MS. This was determined by increases in score on the Expanded Disability Status Scale (EDSS). Patients with abnormal eye movements (n=17) experienced an average EDSS score increase of 1.5 points, while patients with normal eye movement (n=23) experienced an average increase in score of only 0.9 point.
Both groups got worse in terms of MS symptoms even while on drug therapy, but patients who had abnormal ocular motor exams remained more disabled. Sixty percent of patients with abnormal ocular motor scores did show significant changes on magnetic resonance imaging (MRI) in the cerebellum and brain stem, while only 28% of patients who had normal exams experienced such changes as measured by MRI.
"By simple bedside testing," Dr. Derwenskus concluded, "You may be able to predict more severe disease, because eye movement abnormalities reflect lesions in the brain stem and cerebellum."
Individuals with eye problems shouldn't be alarmed by these findings,
however. This is obviously preliminary data, which comes from an extremely
small study. Much further research in this area would need to be conducted
before any definitive conclusions could be drawn. Moreover, a confirmed
link between MS disability and ocular abnormalities could ultimately help
many individuals because physicians could determine early on that they
are candidates for more aggressive treatment.
Copyright © 2003, Real Living with Multiple Sclerosis