DBS for Treatment-resistant Obsessive-compulsive Disorder

The primary purpose of this study is to investigate the effect of deep brain stimulation (DBS) implantation targeting the anteromedial region of subthalamic nucleus (amSTN), or nucleus accumbens (NAc), or bed nucleus of the stria terminalis (BNST), or ventral capsule/ventral striatum (VC/VS), or the ventral anterior limb of the internal capsule (vALIC) in patients with treatment-resistant obsessive-compulsive disorder (TR-OCD).

At least 40-60% of people with obsessive-compulsive disorder (OCD) continue to have symptoms after drug treatment. There is still a lack of effective therapies for TR-OCD. In a comprehensive survey of diverse neuromodulation therapies, targeting specific nuclei with DBS has the most potential for OCD with apparent symptoms. The stimulation targets of DBS for patients with TR-OCD include vALIC, BNST, amSTN, VC/VS, and NAc. For the target site of each individual, it depends on the individualized evaluation results made by the study team. Although DBS is effective and tolerable and has the potential to improve the lives of many patients with TR-OCD, evidence remains limited. To explore its effectiveness, this project plans to conduct DBS-targeted vALIC, BNST, amSTN, VC/ VS, or NAc on RT-OCD patients.

Another goal of this program is to study the neuronal activity of the vALIC, BNST, amSTN, VC/VS, and NAc, respectively. At the same time, some subjects are presented with a task involving an unexpected reward. This separate study is an option and will not affect current study participation.

Some participants will also be invited to join a related study that involves positron emission tomography (PET) scanning to determine how the stimulation changes activity in the brain. Participation in the separate PET study is optional and will not affect current study participation.

Eligibility Criteria:
Inclusion Criteria:

1. aged 18-65;
2. able to provide written informed consent;
3. have a diagnosis of OCD according to the Statistical Manual of Mental Disorders-Fourth Edition-Text Revised (DSM-IV-TR) criteria and confirmed by the Mini-International Neuropsychiatric Interview Chinese version 5.0;
4. have failed to improve despite undergoing two distinct courses of selective serotonin reuptake inhibitors (SSRIs), each lasting a minimum of 3-6 months; have failed to yield therapeutic efficacy after the administration of the maximum dose of clomipramine for 3-6 months in a single trial; without achieving effectiveness under cognitive behaviour therapy for six months; have failed to achieve therapeutic efficacy after three months of atypical antipsychotic medications, singularly or in combination with SSRIs or clomipramine.

Exclusion Criteria:

1. presence of other psychotic disorders;
2. have a treatment history that includes electroconvulsive therapy (ECT), modified electroconvulsive therapy (MECT), transcranial direct current stimulation (tDCS), transcranial alternating current stimulation (tACS), DBS, and transcranial magnetic stimulation (TMS);
3. presents a suicide risk (defined as a HAMD-17 score of ≥3 on suicide-related items);
4. experience difficulty in effectively communicating with investigators;
5. with a history of traumatic brain injury (TBI);
6. with intracranial or cardiovascular stents;
7. substance abuse within the past six months;
8. unstable neurological or coagulation disorders;
9. women who are pregnant, lactating, or of childbearing potential who refuse the use of reliable contraception during the study;
10. have been involved in other clinical studies within three months before enrollment in this study;
11. any conditions unsuitable for conducting this study program considered by the study group.