The purpose of this study is to evaluate the safety and feasibility of using seizure forecasts based on subscalp EEG.

Inclusion Criteria:

Subjects enrolled in this study must have epilepsy involving the temporal lobe and will have undergone video-EEG monitoring within the past 3 years, and will have met the following criteria:

• Focal epilepsy, including complex partial, and secondarily generalized seizures, including:

  • disabling seizure (i.e. involving loss of awareness, motor control, speech, or other essential functions) counts at least 2 per month on average over the preceding 3 months, established by verbal history or caregiver report.
  • For 3 months prior to enrollment, subject's AED dosages have been stable (less than a 25% change in dosage) and subject has had at least two seizures per month, on average, with a seizure-free interval not to exceed 60 days. Seizures must be separated by a minimum of four hours not to be considered part of a cluster. A cluster, for the purpose of this criterion, shall be considered a single seizure.

• With the exception of epilepsy, subject must be medically and neurologically stable.

• Age 18 to 75.

• Ability and willingness to provide informed consent and participate in the study protocol. Subject is able to interpret and to respond, in accordance with the study protocol, to the advisory indicators provided by the device.

• Subject has seizures that are distinct, stereotypical events that can be reliably counted by the subject or caregiver, and have a distinct EEG pattern that can be recorded using subscalp EEG over the frontotemporal head region, established by video-EEG monitoring.

• Subject can reasonably be expected to maintain a seizure diary alone or with the assistance of a competent individual.

• Subject is able to complete regular office visits and telephone appointments in accordance with the study protocol requirements.

• Subject's seizure focus, based upon clinical semiology, scalp EEG, intracranial electroencephalographic (iEEG) findings, and/or neuroimaging, demonstrate consistent involvement of the temporal lobe with their EEG seizure pattern.

• Subject speaks and reads English.

• Subject has no reason to anticipate requiring a magnetic resonance imaging (MRI) evaluation within the next two years.

• Subject has EEG documentation of ictal events consistent with his or her predominant current seizure type.

• Subject's anatomy will permit implantation of the UNEEG SubQ device in the opinion of the study's neurosurgeon.

• Female subjects have a negative pregnancy test, have no plans to become pregnant, and use effective contraception during the study.

Exclusion Criteria:

• For 3 months prior to enrollment, subject's AED dosages have not been stable (greater than 25% change in dosage), or subject has had more than 30 disabling seizures per month, on average, or more than 10 seizure days per month, on average.
• Subject needs to have magnetic resonance imaging during the study period.
• Subject has a substance abuse history (alcohol, prescription, or illicit medications) within the preceding two years.
• Subject participated in another drug or device trial within the preceding 30 days.
• Subject has been hospitalized for a psychiatric condition within the preceding two years or has had a history of psychosis within the preceding two years (excluding post-ictal psychosis).
• Subject is implanted with pacemaker, implantable cardiac defibrillator, cardiac management product, brain stimulator, or other medical device that would interfere with the UNEEG device. This includes, but is not limited to, direct brain neurostimulators, spinal cord stimulators, and cochlear implants. Vagus nerve stimulators are not expected to interfere with the subscalp EEG device and will be permitted, as long as stimulation parameters can be reasonably expected to remain stable (25% or less change in amplitude) throughout the study.
• Subject has experienced unprovoked status epilepticus.
• Subject has had therapeutic surgery to treat epilepsy that may interfere with electrode placement in the judgement of the neurosurgeon.
• Subject is on anticoagulants and is unable to discontinue them perisurgically, as required by the neurosurgeon or Investigator.
• Subject has significant platelet dysfunction from medical conditions or medications (including, particularly, aspirin or sodium valproate). If platelet dysfunction is suspected, subject can be enrolled only if a hematologist, the Investigator, and the neurosurgeon judge it to be advisable. Blood tests to evaluate platelet and bleeding disorder issues will be obtained prior to enrollment.
• Subject is otherwise ineligible for cranial surgery, or the Investigators identify other medical or psychosocial factors that would counter indicate participation in the study.
• Subject is pregnant or intends to become pregnant during the study period.
• Subject has a known diagnosis of psychogenic nonepileptic seizures (PNES)
• Female subject is pregnant or plans to become pregnant.