EffectsOfTranscranialPulseStimulationOnDepression-PilotRCT

• PRIMARY OBJECTIVE: To evaluate the effects of Transcranial Pulse Stimulation (TPS) on symptoms of depression among young adults in Hong Kong.

SECONDARY OBJECTIVES:

• To improve young adults' Anhedonia symptoms after the 2-week TPS intervention and will be maintained at 3-month post-intervention follow-up
• To improve young adults' Instrumental Activities of Daily Living (IADL) after the 2-week TPS intervention and will be maintained at 3-month post-intervention follow-up.
• To improve young adults' Cognition after the 2-week TPS intervention and will be maintained at 3-month post-intervention follow-up.
• Post-MRI scan will show a remarkable structural and functional connectivity in participants' brain after the 2-week TPS intervention compared to pre-MRI scan.

Sample size estimation: To the best of investigator's knowledge, there is only one TPS uncontrolled pilot study conducted on 35 patients with AD in Austria and therefore, we cannot base on their effect size to estimate our sample size in this study. Considering the nature of this study is the first pilot RCT in using TPS in the treatment of depression,investigators aim at recruiting 30 subjects to evaluate the efficacy of our primary and secondary outcomes in this study.

Research plan and Methodology Methods Trial Design: In this study, the investigators will use a single-blind randomized controlled trial design with two-armed repeated measures. The trial design complies with the Consolidated Standards of Reporting Trials (CONSORT) statement. In this two-armed design, investigators will use TPS as an intervention group and a waitlist control group. A waitlist control group is appropriate for comparing the effect of the TPS on the intervention group to that of those not receiving the TPS treatment at the same timepoints Both groups will be measured at baseline (T1), immediately after the intervention (T2) and at the 3-month follow-up (T3). Based on the previous studies, a 3-month follow-up is sufficient to assess the long-term sustainability of the TPS intervention.

Intervention (Transcranial Pulse Stimulation) Purpose of the intervention: The key tenets of the TPS intervention is neuromodulation, i.e., using ultrasound-based brain stimulation techniques to modulate the human brain in a focal and targeted manner. Intervention dose: Each participant should have the pre-treatment MRI scan performed in the University Research Facility in Behavioural and Systems Neuroscience, PolyU prior coming to the first intervention session. All participants (both TPS group and the waitlist control group) will receive six 30 minute-TPS sessions (300 pulse in each session, total: 1800 pulse) in 2 weeks' time (i.e., 3 sessions (Monday, Wednesday, Friday) per week, total: 3 hours). Participants will be followed up at 3-month period after the intervention (Fig 1). The investigators believe that a 2-week TPS intervention is sufficient enough to test the effects of TPS on depressive symptoms.

Inclusion criteria

• Aged 18 or over
• Able to understand/read Chinese
• A HAM-D-17 score of ≥ 8
• Able to provide written informed consent

Exclusion criteria

• Clinical Diagnosis of Major Depressive Disorder (e.g., bipolar affective disorder or schizophrenia)
• Alcohol or substance dependence
• Concomitant unstable major medical conditions or major neurological conditions such as brain tumor, brain aneurysm
• Hemophilia or other blood clotting disorders or thrombosis
• Significant communicative impairments
• Participants with metal implant in brain or treated area of the head
• Participants who undertook corticosteroid treatment within the last six weeks before first TPS treatment
• Pregnant or breastfeeding women.