Retina Recognized As a New Prognostic Marker for Multiple Sclerosis

In order to select the best therapeutic approach, it is imperative to evaluate the severity of multiple sclerosis (MS), but this cannot be done with sufficient accuracy using current techniques.

A new MedUni Vienna study uncovered for the first time that the retina can be used as a prognostic marker. According to analyses, the severity of subsequent MS relapses and, consequently, the chance of impairment, are predicted by retinal layer thinning as a result of those relapses. The study's findings have just been released in Neurology.

A team of researchers led by Gabriel Bsteh and Thomas Berger from the Department of Neurology at MedUni Vienna/University Hospital Vienna and the Department of Ophthalmology and Optometry at the same institution evaluated 167 MS patients over the course of more than three years.

They proposed that the severity of brain damage is reflected in the retinal damage brought on by relapse. According to the results of the scientific studies, the loss of roughly 5 m (micrometers) in retinal layer thickness following optic neuritis results in a doubling of the risk of developing a permanent disability after the subsequent relapse.

The results of the study show that more aggressive treatment is necessary where there is significant retinal layer thinning as opposed to what would be the case for a smaller degree of thinning. These predictions could be utilized as the foundation for treatment decisions in the future. This is true even if the patient has no disability or only slight disability at the time of measurement.

Prognostic technique already available

The researchers measured the thickness of the retinal layer with optical coherence tomography (OCT). OCT is an imaging method that use infrared light to create high-resolution three-dimensional images of incredibly thin tissue layers in the micrometer range (1 micrometer is equal to one thousandth of a millimeter). It is currently employed as a technique for glaucoma diagnosis and disease progression assessment.

The technique for predicting the course of MS is therefore already available to us. As we discovered in the course of our clinical trial, measurements should be taken at initial diagnosis, directly when optic neuritis occurs in relapsing MS, and six months thereafter,” stated Gabriel Bsteh, first author of the study.

The retina is a window to the brain

Multiple sclerosis is a chronic inflammatory autoimmune disease that leads to the loss of axons and neurons across the entire nervous system. Although patients frequently don't initially recognize this damage, the depth of the damage defines how severe the condition will be.

Medical research has been looking for trustworthy prognostic tools for a long time since predictions about the course of the disease are crucial in MS for choosing the right treatment. The key finding of the study, according to Gabriel Bsteh, is that retinal layer thickness "represents a window to the brain, as it were." The method might also be used in standard clinical practice if the findings are verified in larger follow-up investigations.