High Frequency Oscillations in Neurologic Disease


  • Study type

  • Study phase

  • Study IDs

  • Describes the nature of a clinical study. Types include:

    • Observational study — observes people and measures outcomes without affecting results.
    • Interventional study (clinical trial) — studies new tests, treatments, drugs, surgical procedures or devices.
    • Medical records research — uses historical information collected from medical records of large groups of people to study how diseases progress and which treatments and surgeries work best.
  • During the early phases (phases 1 and 2), researchers assess safety, side effects, optimal dosages and risks/benefits. In the later phase (phase 3), researchers study whether the treatment works better than the current standard therapy. They also compare the safety of the new treatment with that of current treatments. Phase 3 trials include large numbers of people to make sure that the result is valid. There are also less common very early (phase 0) and later (phase 4) phases. Phase 0 trials are small trials that help researchers decide if a new agent should be tested in a phase 1 trial. Phase 4 trials look at long-term safety and effectiveness, after a new treatment has been approved and is on the market.

  • Site IRB
    • Rochester, Minnesota: 13-002360
    NCT ID: NCT02235792
    Sponsor Protocol Number: 13-002360

About this study

This study is designed to evaluate the high-frequency range deep brain oscillations (HFO) as pathologic markers in patients undergoing deep brain stimulation for epilepsy or Parkinson disease. Newly developed technology allows for the chronic recording of these brain signals at the same time as clinical stimulation is occuring. We will learn both whether these HFO correlate with disease activity and whether the HFO change in response to ongoing stimulation (potentially giving insight into the underlying mechanism of action of DBS). Study participants will undergo DBS in the same way as is usually done but will receive this newer battery with ability to record brain signals.

Participation eligibility

Participant eligibility includes age, gender, type and stage of disease, and previous treatments or health concerns. Guidelines differ from study to study, and identify who can or cannot participate. If you need assistance understanding the eligibility criteria, please contact the study team.

See eligibility criteria

Inclusion criteria:

  1. Medically-refractory neurologic disease amenable to therapy with deep brain stimulation including:
    1. Idiopathic Parkinson disease with motor fluctuation, dyskinesia, and/or medically refractory tremor despite optimal medical management by a movement disorders neurologist. OR
    2. Unilateral or bilateral mesial temporal lobe (hippocampal) epilepsy with complex partial, and/or secondarily generalized seizures, that is:
      • confirmed through a combination of interictal scalp EEG, ictal scalp EEG under video monitoring, ictal SPECT scanning, and/or invasive EEG monitoring
      • disabling seizure counts >2 per month documented over a 3 month period
      • refractory to at least three antiepileptic drugs given at clinically appropriate maintenance doses resulting in therapeutic plasma levels (in cases where such levels have been established for that particular drug. Drug failures because of side- effects will not be counted toward this total.
      • determined to have mesial temporal lobe epilepsy that is not amenable to resective surgery according to consensus opinion among epileptologists on our institution's multidisciplinary Epilepsy Surgery Committee
  2. Mayo Clinic Deep Brain Stimulation Committee approval for bilateral deep brain stimulation therapy obtained on routine clinical grounds and without reference to this protocol.
  3. Age 18 to 75.
  4. Ability and willingness to provide informed consent and participate in the study protocol.

Exclusion criteria:

  1. Diagnoses other than those included in #1 above.
  2. Comorbid nonepileptic behavioral events or psychogenic movement disorder.
  3. Medical contraindications to DBS surgery.
  4. Psychiatric comorbidities not under stable medical therapy.
  5. Neurodegenerative dementia (cognitive dysfunction resulting from frequent seizure activity will not be an exclusion criteria).
  6. Implanted electronically active medical device with the potential to interfere with intracranial recordings (ex. pacemaker, automatic implantable cardioverter defibrillator (AICD), active vagal nerve stimulator).
  7. Pregnancy; women of child-bearing potential will be required to commit to using an effective method of contraception during the entire duration of the trial. If a subject becomes pregnant despite these precautions, she will be required to report that to our center within two weeks at which point explantation of the experimental device would be an option.

Participating Mayo Clinic locations

Study statuses change often. Please contact us for help.

Mayo Clinic Location Status Contact

Rochester, Minn.

Mayo Clinic principal investigator

Bryan Klassen, M.D.

Open for enrollment

Contact information:

Karla Crockett