Researchers have developed and validated a quick, non-invasive, web-based tool that identifies patients with epilepsy who are unlikely to benefit from invasive stereoelectroencephalography (SEEG).

The 5-SENSE score includes five variables that predict the seizure-onset zone: focal lesion on structural MRI, absence of bilateral independent spikes in scalp electroencephalography (EEG), localizing neuropsychological deficit, strongly localizing semiology, and regional ictal scalp EEG onset.

Online, the 5-SENSE score is a “simple and effective instrument to assist clinicians in reduce unnecessary invasive diagnostic burden on patients and the overuse of healthcare resources that are limited,” the researchers note.

“It takes about 1 minute and can be used directly in the clinic,” Birgit Frauscher (study investigator), Montreal Neurological Institute and Hospital McGill University, Canada, told Medscape Medical News.

The results were published online the 6th of December in JAMA Neurology.

A Reliable Indicator

“SEEG has become the standard to be used in the event of an inconclusive, noninvasive presurgical epilepsy evaluation. However it is estimated that up to 40 percent of patients are not given surgery due to the seizure-onset region is less focused than anticipated or cannot be identified,” the investigators write.

The 5-SENSE score was created in a study of 128 patients (57 women with a median age of 31 years) with epilepsy resistant to drugs. SEEG at the Montreal Neurological Institute to identify a focal seizure-onset zone.

In the development cohort, the 5-SENSE score differentiated those whose SEEG detected the seizure source as a distinct one from those that did not. Area under the curve, specificity, and sensitivity were 0.83, 76.3% and 83.3 percent, respectively.

Researchers validated the score in a larger cohort of 207 patients (97 females average age 32) from nine different Epilepsy Centers that are tertiary. They discovered that it accurately predicted patients for whom SEEG did not reveal the focal seizure start zone. In the validation cohort, the specificity was 76% and sensitivity was 52.3%.

Helpful Tool

David Burkholder MD, a neurologist at the Mayo Clinic in Rochester, Minnesota, was reached for clarification. He said that selecting epilepsy patients with phase II intracranial monitoring or surgery is a long-lasting procedure that isn’t always easy. Scores like these could help in this process.

“In the case of intracranial monitoring phase 2 and SEEG specifically it is crucial to have a clear understanding of the patient’s epilepsy as there is a high possibility of sampling errors resulting in the failure to achieve the intended outcome when there is a lack of understanding or misinterpretation of data,” Burkholder, who was not involved with the study, told Medscape Medical News.

The 5-SENSE tool “forces users to consider their hypothesis in relation to other data that is objective.” A solid hypothesis is likely the most important thing prior to implantation, and adding readily available data that is objective can provide further clinical context,” Burkholder said.

He stated, “It allows some level of uniformity in decision-making the process of making decisions that have often been affected by different cognitive biases. And anything we can do is helpful to remove the biases that affect decision-making.”

Concerning the 5-SENSE score specifically, Burkholder cautioned that the “sensitivity and specificity scores seen in the validation group are less than adequate when it comes down to a definitive clinical value. It’s an indication of how challenging it is to make these decisions and to develop useful tools to help us.

The Fonds of Research du Quebec-Sante and the Montreal Neurological Institute funded this research. Frauscher stated that she received an income from the Fonds de Recherche du Quebec and grants from the Montreal Neurological Institute; personal expenses from Eisai and UCB and grants from Eisai; and that her research is funded in part by the Canadian Institutes of Health Research and the Natural Sciences and Engineering Research Council of Canada. Burkholder has disclosed no relevant financial relationships.

JAMA Neurology. Online publication on December 6 2021.