Obsessive-compulsive disorder (OCD) is an anxiety disorder with a worldwide prevalence of between 1-3 It is characterised by recurrent obsessions and/or compulsions, including but not limited to concerns about contamination and disease, checking and seeking reassurance, safety and hoarding.
Obsessions are persistent and anxiety provoking thoughts, images or impulses which dominate the thinking of an individual. Compulsions are recurrent mental acts or behaviours that often occur in relation to obsessional cues and can act to reduce the experience of anxiety or distress. While, historically, OCD was viewed as a chronic disorder which was intractable and non-responsive to treatment the prognosis has improved with the advent of psychological and pharmacological interventions.
Despite the availability of these treatments 20% to 30% of patients with OCD fail to improve and up to 10% develop a severe intractable form of the illness. For a small proportion of patients with treatment resistant OCD, deep brain stimulation (DBS) may be considered as a possible treatment.
DBS involves the implantation of stimulation electrodes in highly localized brain regions with the aim of modifying brain activity. DBS has been extensively and successfully used in Parkinson's disease, chronic pain, intractable tremor and dystonia. DBS has a number of significant advantages over traditional lesional procedures as it is adjustable, controlled and reversible. Evidence worldwide suggests that DBS for OCD has a response rate of up to 75% and can reduce symptoms by typically up to 60%.
Neuropsychiatry at RMH was the first and remains the only clinical service to offer DBS for OCD within Australia. All patients who proceed to surgery have met the requirements of the Mental Health Review Tribunal who govern the use of Neurosurgery for Mental Illness (for more information, see here).
Comprehensive clinical data is collected during the admission and in regular follow-up appointments, which includes psychiatric measures (self-report, carer scales, clinician rated scales), functional assessments and cognitive assessments.
Preliminary data from the unit has been presented at a variety of national and international conferences and meetings, with results from the first seven patients published in the Australian and New Zealand Journal of Psychiatry (here).
The general eligibility criteria for DBS for OCD include
1. Confirmation of diagnosis of severe, treatment refractory OCD
2. Assessment of medical, surgical and psychiatric history regarding suitability for surgery
3. Capacity to make informed decisions regarding proceeding to surgery.
4. Patients must have a treating psychiatrist outside of their care at RMH Neuropsychiatry.
Following initial referral, patients will be screen via outpatient neuropsychiatrist assessment, and if felt to be suitable, progression to inpatient multidisciplinary assessment, including neurology, neuropsychiatry, neuropsychology, occupational therapy and social work input. If DBS is recommended following this assessment, then a submission is put forward to the Mental Health Review Tribunal for consideration.
Referrals are open to patients across Australia, and can be sent via fax to (03) 9342 8483, or emailed to NPUReferrals@mh.org.au
Dr Sarah Farrand presented on 'DBS for OCD' at the University of Melbourne's Department of Psychiatry Seminar Series in November 2021. https://youtu.be/RTtc_EGv-q8