The American Epilepsy Society held their annual meeting from November 30th to December 4th, 2018 at the New Orleans Ernest N. Morial Convention Center. During the meeting, there were many subjects covered, including the fact that cortical thinning rates indicated that epilepsy is a progressive disorder.
What Was Reported?
At the meeting, researchers reported that the faster pace of cortical thinning in patients who had non-lesional focal epilepsy when “compared with controls indicates that epilepsy is a progressive rather than a static disease.” They utilized magnetic resonance imaging (MRI) scans for cortical thinning in epilepsy patients. Those findings were compared with the healthy matched controls, which provided them with what they consider to be a reliable measure to confirm that epilepsy is progressive.
Marian Galovic, M.D. and a PhD student at University College London, said, “By directly comparing patients with healthy volunteers, we were able to differentiate epilepsy-induced progression from normal aging and this is something that most previous studies struggled with. We demonstrated widespread areas of progressive epilepsy-related atrophy that exceeded aging-related changes that we observed in healthy volunteers.”
How Was The Research Conducted for The Study?
The researchers worked with 190 patients who went through 396 MRI scans and 141 age and sex matched controls who had 242 MRI scans. Each of the individuals who were involved in the test had at least two scans using the same scanner and all scans were more than six months apart from one another.
The researchers discovered that the patients who had epilepsy had a yearly cortical thinning rate of .024 mm. On the other hand, the healthy control patients had a thinning rate of just .011 mm. With the use of a machine learning model, the researchers “found there was progressive atrophy” in 73% of the patients who had epilepsy.
In addition, the researchers investigated further to determine and describe the progressive thinning that was occurring in the cortex. Progressive thinning was most defined on the side of the epileptic focus, but it also affected other areas that were beyond that focus area. Additionally, it frequently affected the other hemisphere. Researchers noted that atrophy was occurring faster with the “earlier onset of epilepsy and in those with hippocampal sclerosis.”
While it might seem likely that progressive atrophy would be linked to the number of seizures a person had, that turned out to not be the case. Surprisingly to the physicians involved with the study, the progressive atrophy was not associated with the frequency of the seizures. Physicians felt that this piece of information will need to be investigated further to verify the results. However, it does support the belief that this type of progressive atrophy in epileptic patients is not always “driven by the direct effects of detectable seizures, but rather represents the ongoing network disruption as an underlying pathogenic process in epilepsy, which could be a seizure-independent phenomenon.” These physicians also believe that the lack of a link to seizure activity could be due to the fact that seizure reports from patients might not always be accurate - there is a possibility that there are more seizures occurring than patients are actually reporting.
Knowing that epilepsy is progressive should encourage doctors to want to accurately diagnose and begin treatment for this condition as soon as possible. Epilepsy is not static and it can worsen over time. Earlier proper diagnosis and treatment is important to the current and future health of the patient. The researchers feel that this is a good first step, but that more study and research needs to be addressed in this area.