Brain atrophy, or wasting, and re-organisation of neurons occur in the brains of people with super-refractory status epilepticus (SRSE), according to a study published in JAMA Neurology. The research also shows that the severity of brain atrophy is related to the duration of SRSE.This is the first study to show that brain atrophy occurs even after difficult-to-treat status epilepticus is controlled with anaesthetic drugs.Dr Sara Hocker, from the Mayo Clinic in Rochester, Minnesota, and co-authors, reported: “In the hours, days, and weeks after prolonged seizures, long-term changes in gene expression” occur. This is accompanied by the chronic rupture of small blood vessels and “results in seizure-induced neuronal death and neuronal reorganization.”During the study, Dr Hocker and her colleagues reviewed the medical records of people with SRSE who were admitted to Mayo Clinic Hospital between 2001 and 2014.A total of 42 people with SRSE were admitted during this time period, 19 of whom met the study criteria: to have had an MRI scan within two weeks of the onset of the SRSE and another MRI within six months of the SRSE resolution, with a minimum of one week between scans. All 19 subjects had received anaesthetic agents to control their seizures.The researchers analysed the participants’ MRI scans, paying particular attention to the area of the ventricles (fluid cavities) compared with the total area of the brain. A ratio of these (ventricular area/total brain area), known as the ventricular-brain ratio, is a common measure of cerebral atrophy or wasting, and a larger ratio suggests a higher degree of wasting.Looking at the scans in two groups (initial MRI and follow-up MRI), the team found that the average ventricular-brain ratio amongst the follow-up scans was significantly larger than the average ventricular area amongst the initial scans. This suggests that wasting of brain matter had occurred.The scientists also discovered that the longer people stayed in hospital and were treated with anaesthetic agents, the more wasting they had in their brain.Finally, they found that the difference in ventricular-brain ratio was smaller in older people with SRSE, but this was probably due to the fact that the older people already had a larger ventricular-brain ratio at the initial MRI due to their age.The study was not able to tell whether cerebral atrophy was caused by complications associated with SRSE or the effect of antiepileptic drugs (AEDs).According to the authors, future studies should focus on which areas of the brain are most affected in SRSE, the association of atrophy with clinical variables, and the influence of atrophy on long-term cognitive function in survivors of SRSE.SRSE is defined as status epilepticus (or a seizure, or series of seizures lasting for five minutes or more) that continues or recurs 24 hours or more after the onset of anaesthetic therapy.Author: Dr Özge ÖzkayaClick here for more articles about brain science including genetics.
August 17th, 2016|