Introduction: A stent retriever (SR) is widely used in mechanical thrombectomy (MT) for M2 segment occlusion. However, the suitable size of SR in M2 occlusion remains unclear. Therefore, we aimed to compare 4 mm-sized SR with 3 mm-sized SR in M2 occlusion. Methods: Patients who underwent MT with SR for M2 occlusion were dichotomized into 4×20 mm SR and 3×20 mm SR groups. Then, 1:1 propensity score matching was performed. The M2 segment was divided into proximal and distal segments according to the occlusion site. Subgroup analysis was then performed for each cohort. Results: A total of 111 patients were enrolled, with 4×20 mm SR and 3×20 mm SR applied in 72 (64.9%) and 39 (35.1%) cases, respectively. In propensity score matching, mean number of stent passages for reperfusion was significantly lower in the 4×20 mm SR group than in the 3×20 mm SR group (1.5 ± 0.8 vs. 2.1 ± 1.1; p = 0.004). First-pass reperfusion (FPR) was more highly achieved in the 4×20 mm SR group than in the 3×20 mm SR group (52.6% vs. 42.1%; p = 0.007). In both proximal and distal occlusion cohorts, the 4 mm SR group showed lower mean number of SR passage (p = 0.004 and p =0.003, respectively) and higher FPR rate than the 3 mm SR group (p = 0.003 and p = 0.007, respectively). Conclusion: In MT for M2 occlusion, 4×20 mm SR enables an effective procedure with lesser SR passage for reperfusion and a higher rate of FPR than 3×20 mm SR. result: A total of 111 patients were enrolled, with 4×20 mm SR and 3×20 mm SR applied in 72 (64.9%) and 39 (35.1%) cases, respectively. In propensity score matching, mean number of stent passages for reperfusion was significantly lower in the 4×20 mm SR group than in the 3×20 mm SR group (1.5 ± 0.8 vs. 2.1 ± 1.1; P = 0.004). First pass reperfusion (FPR) was highly achieved in the 4×20 mm SR group than in the 3×20 mm SR group (52.6% vs. 42.1%; P = 0.007). In both proximal and distal occlusion cohorts, the 4 mm SR group showed lower mean number of SR passage (P = 0.004 and P =0.003, respectively) and higher FPR rate than the 3 mm SR group (P = 0.003 and P = 0.007, respectively).

中文翻译：

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4 mm 和 3 mm 支架回收器在 M2 闭塞机械取栓中的比较

简介：支架取栓器 (SR) 广泛用于 M2 段闭塞的机械取栓术 (MT)。然而，M2 闭塞中 SR 的合适大小仍不清楚。因此，我们的目的是比较 4 毫米尺寸的 SR 和 3 毫米尺寸的 SR 在 M2 咬合中的情况。方法：因 M2 闭塞而接受 MT 和 SR 的患者分为 4×20 mm SR 和 3×20 mm SR 组。然后进行1:1倾向得分匹配。 M2段根据闭塞部位分为近端段和远端段。然后对每个队列进行亚组分析。结果：共纳入111例患者，其中应用4×20 mm SR和3×20 mm SR的患者分别为72例（64.9%）和39例（35.1%）。在倾向评分匹配中，4×20 mm SR 组再灌注的平均支架通道数显着低于 3×20 mm SR 组（1.5 ± 0.8 vs. 2.1 ± 1.1；p = 0.004）。 4×20 mm SR 组的首过再灌注 (FPR) 高于 3×20 mm SR 组（52.6% vs. 42.1%；p = 0.007）。在近端和远端闭塞队列中，4 mm SR 组显示出比 3 mm SR 组更低的平均 SR 通道数（分别为 p = 0.004 和 p = 0.003）和更高的 FPR 率（p = 0.003 和 p = 0.007，分别）。结论：在 M2 闭塞的 MT 中，4×20 mm SR 能够实现有效的手术，与 3×20 mm SR 相比，再灌注的 SR 通道更少，并且 FPR 率更高。结果：共纳入111例患者，其中应用4×20 mm SR和3×20 mm SR的患者分别为72例（64.9%）和39例（35.1%）。在倾向评分匹配中，4×20 mm SR 组再灌注的平均支架通道数显着低于 3×20 mm SR 组（1.5 ± 0.8 vs. 2.1 ± 1.1；P = 0.004）。 4×20 mm SR 组的首过再灌注 (FPR) 高于 3×20 mm SR 组（52.6% vs. 42.1%；P = 0.007）。在近端和远端闭塞队列中，4 mm SR 组显示出比 3 mm SR 组更低的平均 SR 通道数（分别为 P = 0.004 和 P = 0.003）和更高的 FPR 率（P = 0.003 和 P = 0.007）。分别）。