Amount, location, size of brain lesions can determine advancement to MS

Identifying the amount, location and size of lesions on MRI can predict the risk of progression from an early stage of multiple sclerosis (MS) to an official diagnosis within a year, according to authors of a new Brain and Behavior study.

Most patients eventually diagnosed with MS first present with clinically isolated syndrome (CIS)—the first of the four disease courses associated with the central nervous system disease.

At this stage, 50 to 70 percent of patients undergo an MRI that typically shows multiple white matter brain lesions that indicate MS. Some studies have shown about 30 percent of those with an abnormal MRI have an episode resulting in MS within one year. Others show up to 20 percent don’t have another indication for at least 20 years.

Due to this wide variance, researchers looked at medical records of 46 patients with an episode of CIS who were also followed clinically and imaged for the following year. A neuroradiologist reviewed the images without clinical data and identified the number, location and largest longitudinal diameter of the lesions.

One year after initial MRI, 25 (54 percent) patients progressed to MS.

CIS patients with lesions in the temporal lobe, occipital lobe or perpendicular to the corpus callosum were more likely to experience another clinical episode.

Those patients with a combination of more than 13 lesions, a maximal diameter more than 0.75 cm and lesions perpendicular to the corpus callosum experienced a 19 times greater chance of advancing toward MS in the following year.

“Our research succeeded in identifying a combination of parameters, including location, the number of lesions, and the maximal length of the lesion that showed significant predictive value during the year following the first MRI,” wrote lead author Ayelet Eran, with Rambam Health Care CampusHaifa in Israel, and colleagues. “Importantly, the method is simple and can be implemented by every physician when using MRI, to identify progression to MS.”