The purpose of this study is to examine the effects of sub-callosal cingulate (SCC) deep brain stimulation (DBS) in patients with treatment resistant depression (TRD).

The working hypotheses are that long pulse-width DBS applied to the SCC region will lead to improvements in TRD patients, and specific neuroimaging biomarkers will correlate with response to DBS; the functional recovery will be enhanced with concurrent cognitive behavioural therapy (CBT).

The aim is to collect data on prediction, optimization and augmentation of DBS for TRD and develop tools for DBS surgery. It is a biological pilot study designed to provide informative data for future work.

Inclusion Criteria:

• age 20-70
• diagnosis of major depressive (MDD)or bipolar disorder(BP)determined independently by 2 study psychiatrists
• current major depressive episode of >1 year duration, treatment-resistant (meaning failure to respond to 4 different classes of antidepressants, including augmentation or combination strategies with lithium, atypical antipsychotics, anticonvulsants, antidepressants, evidence-based psychotherapy, CBT, or electroconvulsive treatment despite adequate dosage, duration and compliance)
• minimum score of 20 (out of 52) on the 17 item Hamilton Depression Rating Scale (HDRS)
• resident of Alberta, Canada, covered by Alberta Health

Exclusion Criteria:

• other Axis I psychiatric disorders including schizophrenia, psychosis, active suicidal ideation over previous 6 months
• cerebrovascular risk factors, previous stroke, head injury and neurodegenerative disorders, pregnancy, medical and general contraindications for DBS surgery (e.g. cardiac pacemaker/defibrillator)
• age >70
• diabetes

undecided