Adjunctive Periprocedural Sonolysis During Carotid Revascularization: A Bayesian Meta-Analysis

Background: Periprocedural cerebral ischemia remains an important complication of carotid revascularization and is frequently attributed to microthromboembolism during carotid endarterectomy (CEA) and carotid artery stenting (CAS). Sonolysis, the continuous application of low-intensity 2-MHz transcranial Doppler ultrasound, has been proposed as a noninvasive adjunctive strategy to enhance endogenous fibrinolysis and reduce embolic cerebral injury. Hypothesis: Adjunctive periprocedural sonolysis reduces clinical cerebrovascular events and subclinical ischemic brain injury during carotid revascularization without increasing hemorrhagic complications. Methods: PubMed, Embase, and Cochrane databases were systematically searched through June 2026 for randomized trials comparing adjunctive periprocedural sonolysis with sham or standard care during CEA or CAS. The primary endpoint was 30-day ischemic stroke or transient ischemic attack (TIA). Secondary outcomes included new post-procedural diffusion-weighted imaging (DWI) lesions and large DWI lesions (≥0.5 mL) on 24-hour brain MRI. Bayesian random-effects meta-analysis with weakly informative half-normal priors was performed to account for sparse-event structure and the limited number of studies. Posterior probabilities of benefit were calculated. Frequentist Hartung-Knapp analyses and alternative Bayesian priors were performed as sensitivity analyses. Results: Three sham-controlled randomized trials involving 1,343 randomized patients were included, of whom 799 underwent post-procedural MRI assessment. Adjunctive sonolysis was associated with a lower risk of 30-day stroke or TIA versus control (posterior RR 0.31, 95% credible interval [CrI] 0.12-0.82), with posterior probability of benefit of 98.4%. Sonolysis was also associated with a directional reduction in new DWI lesions (posterior RR 0.65, 95% CrI 0.41-1.03; P[RR<1]=96.9%) and a lower risk of large DWI lesions ≥0.5 mL (posterior RR 0.33, 95% CrI 0.16-0.67; P[RR<1]=99.7%). Findings remained directionally consistent across prior sensitivity analyses and frequentist Hartung-Knapp models. No increase in intracranial hemorrhage or major bleeding complications was observed across included trials. Conclusions: In randomized sham-controlled studies, adjunctive periprocedural sonolysis was associated with reductions in both clinical cerebrovascular events and imaging-defined ischemic brain injury during carotid revascularization. Although the evidence base remains limited, the concordant reductions across clinical and imaging-defined ischemic outcomes, without evidence of increased hemorrhagic complications, support further evaluation of sonolysis in larger contemporary multicenter trials.