What a simple eye test might predict about MS
A simple look into the eye could help clinicians know how fast multiple sclerosis (MS) will progress. Results of a new study show retinal thinning – the membrane that covers the inner eye – thins at a fast rate when MS occurs early and progresses rapidly.
For the study, Johns Hopkins investigators followed 164 patients from the MS clinic for 21 months. They measured the thickness of the retina every 6 months for the duration of the study period – 59 of the patients had no disease activity.
The test is performed with a test known as OCT (optical coherence tomography) that can be performed in the doctor’s office. Patients in the study also underwent brain scans (MRI) at the start of the investigation and then yearly.
The finding showed people with active MS had 42 percent faster thinning of the retina compared to those whose disease was in remission.
Patients with multiple sclerosis with gadolinium-enhancing lesions, or ‘bright spots’ that appear on MRI and signal active disease, had 52% faster thinning of the retina.
Another type of scan commonly used to gauge activity of the disease is called a T2 weighted scan, also performed using magnetic resonance imaging. They also appear as bright lesions on MRI.
In the study T2 lesions were associated with 32% more rapid thinning of the eye membrane, compared to patients who did not have the activity on MRI.
Early MS - less than 5 years - was associated with 43 percent faster thinning, compared to patients who had been diagnosed with the disease more than 5 years. There was 37 percent less thinning among patients who had no change in their level of disability.
Changes in the retina of the eye have been a source of interest for researchers. Scientists know the disease is associated with inflammation and atrophy.
MS is believed to be an autoimmune disease that attacks the lining of nerves in the brain, known as myelin, which is what leads to symptoms of lack of coordination and vision problems. There is no cure for the disease. Symptoms vary widely between patients. Some people do well with no treatment, while others experience devastating symptoms.
Treatment is geared toward slowing down progression of the disease that can come and go. For other patients, MS progresses rapidly.
The finding suggests a simple eye test could be used to measure the effectiveness of therapies used to treat the disease. Nerve cells in the retina of the eye don’t have a myelin sheath like brain cells do. Retinal thinning that can be performed with a simple eye exam might be an early sign that MS is progressing.
"Active MS is associated with accelerated retinal ganglion cell/inner plexiform layer thinning"
John N. Ratchford, MD, et al
January 1, 2013