A Pilot Study: Focused Ultrasound Thalamotomy for the Prevention of Secondary Generalization in Focal Onset Epilepsy

Prior treatment

• Previous corpus callosotomy (surgery to cut the fibers, called the corpus callosum, that separate each half of the brain).

Other illness

• Have on average less than 3 seizures a month.
• Have severe untreated neuropsychiatric disorders (e.g., untreated depression or behavioral problems).
• History of drug or alcohol abuse in the last 12 months.
• Presence of primary generalized epilepsy (e.g., Lennox Gastaut, drop attacks).
• Presence of post-infectious epilepsy (i.e., epilepsy from post-herpetic encephalitis).
• Unable or unwilling to maintain your current anti-seizure drug dosage for 3 months post-treatment.
• History of claustrophobia (fear of closed spaces).
• Uncontrolled hypertension or other comorbid conditions (e.g., uncontrolled heart or lung disease).

Other

• Have an indwelling vagal nerve stimulator.
• Significant structural brain abnormalities.
• Pregnant or not practicing birth control methods.
• Presence of an MRI contraindicated implanted metal or medical device (e.g., pacemaker, metallic joints, or insulin pump).
• Skull Density Ratio (SDR) \<0.4.
• IQ score of \<70 on the Wechsler Advanced Clinical Solutions - Test of Premorbid Functioning (TOPF), a measure conducted as part of baseline neuropsychological assessment.

• Medically refractory epilepsy (≥2 antiepileptic drug failures) deemed disabling by the patient and study investigators.
• Focal seizures with secondary generalization; with or without primary generalized seizures.
• ≥ 3 seizures/month on average based on seizure diary of patient's preferred format during the three months prior to enrollment.
• Stable prescribed epilepsy medication dosages, including stopping or starting medication, for 3 months before enrollment.
• Anterior Nucleus (AN) identifiable on MRI (structural T1 and T2 images).
• Willing to maintain seizure diary (3 months before \& 3 months after the study treatment).
• Involved caregiver such as a spouse, family member, or family friend willing to provide reliable care during the study participation.
• Ability to provide written informed consent to participate.
• Previous seizure work-up to include:
  • Home EEG, Epilepsy Monitoring Unit (EMU) video EEG, or intracranial EEG.
  • Baseline neuropsychological assessment, which includes the Wechsler Advanced Clinical Solutions - Test of Premorbid Functioning (TOPF). Participants obtaining an Intelligence Quotient (IQ) score of ≥70 on the TOPF will be included.
  • High-definition MRI imaging/Position emission tomography (PET) imaging.