Flow reversal strategy for symptomatic vertebrobasilar dolichoectasia: a single-center experience with ECA-RA-PCA...

Symptomatic vertebrobasilar dolichoectasia (VBD) is associated with an extremely poor natural prognosis and presents significant clinical challenges. This study aims to evaluate the safety and efficacy of a flow reversal strategy based on extracranial carotid artery-radial artery-posterior cerebral artery (ECA-RA-PCA) bypass, combined with individualized proximal parent artery intervention, for the treatment of symptomatic VBD. We retrospectively analyzed the clinical data of 23 consecutive patients with symptomatic VBD treated with microsurgery between October 2019 and July 2025. Patients were categorized into ischemia-dominant (n = 13), compression-dominant (n = 8), and hemorrhage-dominant (n = 2) subtypes based on their primary clinical presentation. All patients underwent ECA-RA-PCA bypass. Differentiated treatment strategies were implemented based on clinical subtypes: ischemia-dominant patients mostly received bypass alone (12/13, 92.3%), whereas compression-dominant (6/8, 75.0%) and hemorrhage-dominant (2/2, 100%) patients primarily underwent bypass combined with proximal occlusion. Surgical success was achieved in all cases, with a graft patency rate of 100% intraoperatively and during follow-up. Over a median follow-up of 38 months (IQR 23-51), 69.6% (16/23) of patients achieved radiographic improvement (43.5% with lesion regression and 26.1% with obliteration), with no instances of aneurysm rupture or progression. The median Modified Rankin Scale (mRS) score improved from 3 (IQR 2-4) preoperatively to 2 (IQR 1-4) at the last follow-up. The overall favorable clinical outcome rate was 69.6%; the ischemia-dominant group achieved the highest favorable rate (84.6%), followed by the compression-dominant group (62.5%). Major complications included brainstem infarction (30.4%) and pneumonia (39.1%), both of which occurred at higher rates in the compression and hemorrhage groups. For complex symptomatic VBD unsuitable for conventional endovascular treatment, an individualized flow reversal strategy based on ECA-RA-PCA bypass and clinical subtyping is a feasible and effective therapeutic option, albeit with inherent high surgical risks. This strategy maintains long-term flow patency, promotes benign remodeling of the diseased vessel, and may be associated with favorable long-term neurological outcomes in carefully selected patients.