The efficacy and cerebral hemodynamics mechanisms of acupuncture on the posterior circulation ischemic stroke with vertigo: study protocol for a multicenter, randomized, controlled trial.

INTRODUCTION: Posterior circulation ischemic stroke (PCIS) with vertigo is a common central vertigo disease that significantly hinders patients' motivation for rehabilitation and increases the recurrence rate and mortality among stroke patients due to recurrent episodes of vertigo. Acupuncture has shown promising therapeutic effects in the treatment of PCIS with vertigo, but its underlying mechanisms remain unclear. This study is designed to investigate the impact of acupuncture on cerebral hemodynamics and brain structure in PCIS patients vertigo, and to evaluate its clinical effectiveness in managing this condition.

METHODS AND DESIGN: This is a multicenter, randomized, controlled trial that will randomly allocate 234 participants in a 1:1:1 ratio to manual acupuncture group, sham acupuncture group, or western medication group. This trial is primarily designed as an explanatory trial, with the primary comparison being manual acupuncture vs. sham acupuncture to evaluate the specific efficacy of acupuncture; comparisons between acupuncture and western medication are regarded as secondary comparative effectiveness analyses. All groups will receive standard secondary stroke prevention. Manual and sham acupuncture will be administered five times weekly for 3 weeks (30 min/session), while the western medication group will receive oral betahistine mesilate tablets three times daily, 5 days per week, for 3 weeks. Assessments will be conducted at baseline (Week 0), post-treatment (Week 3), and at Week 11. The primary outcome is the Dizziness Handicap Inventory (DHI); secondary outcomes include the Dizziness and Anxiety Rating Scale (DARS), dizziness diaries and adverse event rate during the follow-up period. To test the a priori hypothesis that acupuncture improves dizziness by modulating posterior circulation hemodynamics and regional cerebral perfusion in vestibular-related brain regions, cerebral hemodynamics and brain imaging changes will be assessed using transcranial Doppler (TCD), structural magnetic resonance imaging (sMRI), and arterial spin labeling MRI (ASL-MRI) at baseline (Week 0) and post-treatment (Week 3). We specifically hypothesize that acupuncture will increase mean flow velocity (MFV) and reduce resistance index (RI) in the vertebral arteries, basilar artery, and posterior cerebral arteries, enhance regional cerebral perfusion in vestibular-related brain areas, and induce structural changes associated with vestibular compensation.

DISCUSSION: This study will provide robust evidence on the safety and efficacy of acupuncture for vertigo with PCIS. In addition, it will test a prespecified biological hypothesis that acupuncture may relieve dizziness by improving vertebrobasilar hemodynamics and regional perfusion within vestibular-related brain networks, with corresponding imaging changes associated with clinical improvement. This research aims to offer novel insights into acupuncture as a potential therapeutic approach for vertigo following PCIS.

CLINICAL TRIAL REGISTRATION: [chictr.org.cn], identifier [ChiCTR2400087030].