RT Journal Article SR Electronic T1 Tailored Vessel-Catheter Diameter Ratio in a Direct Aspiration First-Pass Technique: Is It a Matter of Caliber? JF American Journal of Neuroradiology JO Am. J. Neuroradiol. FD American Society of Neuroradiology DO 10.3174/ajnr.A6987 A1 E. Pampana A1 S. Fabiano A1 G. De Rubeis A1 L. Bertaccini A1 A. Stasolla A1 A. Vallone A1 A. Pingi A1 M. Mangiardi A1 S. Anticoli A1 C. Gasperini A1 E. Cotroneo YR 2021 UL http://www.ajnr.org/content/early/2021/01/21/ajnr.A6987.abstract AB BACKGROUND AND PURPOSE: The aspiration technique has gained a prominent role in mechanical thrombectomy. The thrombectomy goal is successful revascularization (modified TICI ≥ 2b) and first-pass effect. The purpose of this study was to evaluate the impact of the vessel-catheter ratio on the modified TICI ≥ 2b and first-pass effect.MATERIALS AND METHODS: This was a retrospective, single-center, cohort study. From January 2018 to April 2020, 111/206 (53.9%) were eligible after applying the exclusion criteria. Culprit vessel diameters were measured by 2 neuroradiologists, and the intraclass correlation coefficient was calculated. The receiver operating characteristic curve was used for assessing the vessel-catheter ratio cutoff for modified TICI ≥ 2b and the first-pass effect. Time to groin puncture and fibrinolysis were weighted using logistic regression. All possible intervals (interval size, 0.1; sliding interval, 0.01) of the vessel-catheter ratio were plotted, and the best and worst intervals were compared using the χ2 test.RESULTS: Modified TICI ≥ 2b outcome was achieved in 75/111 (67.5%), and first-pass effect was achieved in 53/75 (70.6%). The MCA diameter was 2.1 mm with an intraclass correlation coefficient of 0.92. The optimal vessel-catheter ratio cutoffs for modified TICI ≥ 2b were ≤1.51 (accuracy = 0.67; 95% CI, 0.58–0.76; P = 0.001), and for first-pass effect, they were significant (≤1.33; P = .31). The modified TICI ≥ 2b odds ratio and relative risk were 9.2 (95% CI, 2.4–36.2; P = 0.002) and 3.2 (95% CI, 1.2–8.7; P = .024). The odds ratio remained significant after logistic regression (7.4; 95% CI, 1.7–32.5; P = .008). First-pass effect odds ratio and relative risk were not significant (2.1 and 1.5; P > .05, respectively). The modified TICI ≥ 2b best and worst vessel-catheter ratio intervals were not significantly different (55.6% versus 85.7%, P = .12). The first-pass effect best vessel-catheter ratio interval was significantly higher compared with the worst one (78.6% versus 40.0%, P = .03).CONCLUSIONS: The aspiration catheter should be selected according to culprit vessel diameter. The optimal vessel-catheter ratio cutoffs were ≤1.51 for modified TICI ≥ 2b with an odds ratio of 9.2 and a relative risk of 3.2.ADAPTa direct aspiration first‐pass techniquemTICImodified TICI