Subcutaneous EEG in Epilepsy

Inclusion Criteria: 1. Semiology of some seizures compatible with mesial temporal lobe involvement. 2. Paraclinical findings supporting mesial temporal seizure focus. Such proof may consist of: * previous EEG recording interpreted as compatible with mesial temporal involvement OR * radiological findings demonstrating pathology in the mesial temporal area (CT, MRI, FDG-PET or SPECT). 3. Age 18-90. 4. Current seizure frequency (fulfilling criteria 1) of more than one per week to be eligible to EMU admission or 1 per month for direct enrollment to home monitoring (by own account). 5. Available for the duration of the study (6 months from screening). Exclusion Criteria: 1. Known disorder of hemostasis. 2. Daily or frequent (more than 2 days per week) treatment with any drugs of the following types: * antiplatelets * anticoagulants * chemotherapeutics * non-steroid anti-inflammatory drugs (NSAID) * omega 3 fatty acids (fish oil) 3. Skeletal deformities or damage at the proposed implantation site to an extent that impedes correct electrode placement. 4. Scheduled facial or cranial surgery within 6 months from enrollment. 5. Active deep brain stimulation device. 6. Presence of implanted ICD pacemaker, cochlear implant or other active implants. 7. Planned transcranial magnetic stimulation (TMS) or transcranial direct current stimulation (tDCS) in the duration of the study. 8. Presence of any implanted device at the proposed site of implantation. 9. Known allergy towards any material that is part of the investigational device. 10. Females of childbearing potential who are pregnant, intend to become pregnant, or are not using adequate contraceptive methods throughout the study. 11. Performing extreme sport, including scuba diving (snorkel diving is allowed), parachute jumping or martial arts. 12. Scheduled MRI within 5 months from enrollment. 13. Work involving operation of MRI-scanner. 14. Operating hand held transceivers for communication (e.g. within the police, medical, fire, air traffic control, marine or military). 15. Working at broadcast stations for television or FM/DAB radio. 16. Known or suspected abuse of alcohol defined as estimated consumption beyond that, which is recommended by the DHA or any other neuro-active substances. 17. Active vagus nerve stimulator. 18. Skin disorders near the proposed implantation site, including infection. 19. Contraindications against the local anesthetic drug used during im- and explantation. 20. Diabetes of any kind. 21. Psychiatric disorders including: * schizophrenia * bipolar affective disorder * emotionally unstable personality disorder * schizoaffective disorder * schizotypal disorder * autism 22. Severely abnormal paraclinical findings or vital signs: * S-creatinine ≥ 3 times upper reference value * ALAT, alkaline phosphatase or bilirubin≥ 3 times upper reference value * APTT \> 50 seconds * thrombocyte count \< 50 or \>1000 x 10\^9/l * INR ≥ 1,6 * HgBA1C \> 55 mmol/mol * Any ECG finding requiring immediate referral to a cardiologist as assessed by the investigator * pulse \<40 bpm or \>120 bpm or suspicion of atrial fibrillation by auscultation * temperature \>38 ºC * respiration rate \>30 pr. minute * systolic blood pressure \< 80 mmHg or \>220 mmHg and diastolic blood pressure \<50 mmHg or \>120 mmHg * any other clinical or paraclinical finding suggesting known or unknown illness or disorder requiring immediate treatment as assessed by the investigator