Blog #129: IS YOUR SEIZURE FREQUENCY PREDICTABLE?

 

The longest seizure study yet finds daily, weekly, monthly, and yearly seizure repeating cycles based on continuous intracranial EEG data collected from 2004 to 2018. Patients often tell their doctors that their seizures come in cycles. Skeptical physicians may now acknowledge their patients’ reports and approach their patients with more effective treatment adjustments. ¹

Blog #41, December 24, 2013, appearing on LanceFogan.com describes an implantable neurostimulator approved by the FDA in November 2013. The device is called the Responsive Neurostimulation System (RNS NeuroPace, Inc.). It is surgically implanted into the skull bone—not under the bone—close to the brain location where the seizures are determined to originate. Two small holes are drilled into the bone through which two lead wire electrodes are placed on the brain, or within it, close to a seizure focus. The battery-powered stimulator positioned outside the brain on the skull monitors brain activity. When the onset of seizure activity is detected the electrodes deliver stimuli that short-circuit the abnormal brain activity and normalize it before a seizure manifests. The RNS System activates only when it detects seizure activity. It aborts many seizures from manifesting even before the person is aware of the imminent seizure.

The NeuroPace stimulator detects circadian cycle data in epilepsy. Circadian rhythm is a natural internal process that regulates sleep-wake cycles and other processes in an organism. It repeats roughly every 24 hours. In some people with epilepsy, seizures occur in predictable cycles. Have you noted some of your seizures are predictable?

Circadian seizure cycles showed five peaks of epileptiform activity: morning, mid-afternoon, evening, early night and late night. If these findings pan out on further research, perhaps augmenting anti-seizure medications at predictable times may prevent some of your seizures. Knowledge of when seizures can be expected should empower patients. This knowledge can boost self-confidence. Driving ability, employment, social disablement all impact the lives of people with epilepsy; this predictable-seizure knowledge can return confidence and independence. 

This new approach to assessing seizure-frequency by constant EEG recording with the NeuroPace device shows many individuals’ seizures occur every seven, 15, 20 or 30 days. Epilepsy researchers were surprised at this predictable cyclic information and are considering whether seizure forecasting over long time periods can be done. A seven-day cycle is often not precisely 7 days; it might be 6.5 or 7.5 days. As patient’s known cycles, i.e., weekly or 15 or 20 or 30 days or longer approaches patients may predict their seizure and take safeguarding action. Researchers are excited to follow up these findings.

 

1)      Neurology Today: Longest6 seizure study yet finds daily, weekly, monthly and yearly cycles. Reviewed by Dan Hurley in the March 18, 2021 issue, page 10-11.

 

 

Lance Fogan, M.D. is Clinical Professor of Neurology at the David Geffen School of Medicine at UCLA. “DINGS” is a medical mystery and his first novel. It is a mother’s dramatic family story that teaches epilepsy, now available in eBook, audiobook and soft cover editions.