Finding epilepsy hotspots before surgery: A faster, non-invasive approach

Neurosurgery for sufferers with drug-resistant epilepsy requires finding the exact mind areas which might be producing the seizures. Typically, sufferers endure seven to 10 days of invasive intracranial EEG monitoring, with electrodes surgically implanted contained in the mind by means of a number of cranium openings to seize seizure exercise because it occurs.

Eleonora Tamilia, Ph.D., directs the Epilepsy Monitoring Unit Signal and Data Science Program inside the Epilepsy Center at Boston Children’s Hospital. Her group has piloted a a lot briefer technique for mapping seizure zones.

Not solely is it noninvasive, however can it present info a standard EEG studying can not. It combines customary scalp EEG readings with MRI knowledge on mind construction to establish connections between completely different areas of the mind and makes use of machine studying to find probably the most epileptogenic mind areas.

“Using computational instruments, we are able to reconstruct cortical exercise that the attention can not catch and perceive how completely different areas are functionally related,” explains Tamilia, who can also be a part of the Fetal-Neonatal Developmental Science Center (FNNDSC). “If a seizure begins in a single area of the cortex, it is prone to unfold to a different community it connects to. Even areas which might be far aside might fireplace collectively.”

Predicting seizure zones

As described in Epilepsia, Tamilia and her colleagues retrospectively analyzed about 5 minutes of scalp EEG knowledge from 50 sufferers with drug-resistant epilepsy who had neurosurgery.

Adding MRI knowledge and utilizing machine studying algorithms, they have been in a position to outline useful cortical networks—even throughout instances when no epileptiform exercise was seen to the bare eye and even when the MRI confirmed no apparent mind abnormalities.

“When there have been spikes on the EEG, our predictions have been extra exact, however we may nonetheless get an estimate with out them,” Tamilia says.

During epileptiform exercise, the algorithm achieved 75% accuracy (91% sensitivity, 74% specificity) in figuring out the surgically focused seizure zones. During quiet durations, it achieved 62% accuracy.

The algorithm was much less prone to match the focused zones in sufferers who continued to have seizures after surgical procedure, suggesting that the carried out surgical plan didn’t truly pinpoint the seizure focus. “This means that the plan may have been modified,” Tamilia says. “In instances of unsuccessful surgical procedure, the mannequin indicated epileptogenic areas that weren’t utterly eliminated.”

The software may additionally point out that the epilepsy space is simply too broad to resect, and that sufferers might as an alternative profit from different palliative remedies resembling neuromodulation, she provides.

The researchers now hope to validate their findings in a bigger, potential cohort and outline which sufferers with drug-resistant epilepsy are most certainly to learn from surgical procedure. Because their method is transient and noninvasive, it could possibly be used early in the middle of illness, Tamilia says.

This may allow some youngsters to have epilepsy surgical procedure sooner somewhat than later, avoiding a few of epilepsy’s neurodevelopmental outcomes.