RT Journal Article SR Electronic T1 Use of a sheathless 8-French balloon guide catheter (Walrus) through the radial artery for mechanical thrombectomy: technique and case series JF Journal of NeuroInterventional Surgery JO J NeuroIntervent Surg FD BMJ Publishing Group Ltd. SP neurintsurg-2021-017868 DO 10.1136/neurintsurg-2021-017868 A1 Rimal H Dossani A1 Muhammad Waqas A1 Andre Monteiro A1 Justin M Cappuzzo A1 Faisal Almayman A1 Kenneth V Snyder A1 Elad I Levy A1 Adnan H Siddiqui A1 Jason M Davies YR 2021 UL http://jnis.bmj.com/content/early/2021/08/23/neurintsurg-2021-017868.abstract AB Background The effectiveness of transradial stroke thrombectomy has been limited by guide catheter size and lack of good balloon options. In this study we describe our technique for the use of a sheathless 8-French balloon guide catheter (Walrus) through radial access and present our initial clinical experience.Methods This was a retrospective case series of consecutive patients who underwent mechanical thrombectomy for large vessel occlusion using the sheathless catheter over a period of 3 months. Clinical characteristics, procedural details, reperfusion success (modified Thrombolysis in Cerebral Infarction (mTICI) 2b–3 grade), first-pass effect (FPE; mTICI reperfusion grade 2c or 3 with a single pass), access site complications and clinical improvement at discharge were recorded. A descriptive analysis was performed.Results Among the 10 patients in the series, median age was 77 years (IQR 75–79) and three were women. All patients had a baseline modified Rankin Scale score ≤2. Median admission National Institutes of Health Stroke Scale (NIHSS) score was 12.5 (IQR 9–16). Four patients received intravenous alteplase before mechanical thrombectomy. Eight patients had M1 occlusion and two had proximal M2 occlusion. The median radial artery diameter was 2.5 mm (IQR 2.5–2.7). Successful reperfusion was achieved in all patients. FPE was achieved in six patients. No access site-related complications or post-procedural intracranial hemorrhages occurred. All patients had improvement in NIHSS score at discharge.Conclusions The use of this sheathless catheter for transradial access was safe and feasible. The technique can potentially improve the outcomes of transradial access for stroke intervention.