Recanalization of Tandem Vertebrobasilar Occlusions with Contralateral Vertebral Occlusion or Hypoplasia via either Direct Passage or the SHERPA Technique.

INTRODUCTION: Tandem vertebral ostial disease with acute intracranial vertebrobasilar occlusion with contralateral vertebral occlusion or hypoplasia presents a unique challenge to the interventionalist.
METHODS: The authors queried a prospectively maintained institutional endovascular database from August 2013 to June 2018 for cases of endovascularly treated acute tandem vertebrobasilar occlusions in the presence of contralateral vertebral occlusive disease or hypoplasia. Demographic and presentation data, the technique, results, and clinical outcome were extracted.
RESULTS: Tandem recanalization was attempted and achieved in 5 patients with a thrombolysis in cerebral infarction (TICI) 3 result in 4 patients and a TICI 2c result in 1 patient. To facilitate effective manual aspiration thrombectomy for the tandem basilar occlusion, performed in all cases in 1 or 2 passes, the Neuron^TM MAX sheath was advanced into the V2 after Dotter or balloon angioplasty of the diseased origin. In cases where the origin cannot be crossed/visualized, the Synchro Helper to Evaluate via Retrograde Passage an Arterial origin (SHERPA) technique, entailing the passage of a microwire retrograde via the hypoplastic contralateral vertebral artery was utilized to delineate the vertebral ostium (n = 2 cases). All but 1 patient had substantial improvement in the National Institutes of Health Stroke Scale score after the procedure.
CONCLUSION: Recanalization of tandem vertebrobasilar occlusions with contralateral occlusion or hypoplasia is feasible. Intracranial recanalization is facilitated by the passage of a long 6F sheath into V2, and retrograde delineation of an occluded vertebral origin with a microwire may serve as a crucial adjunct.