CHRU Hospitaux de Tours, UMR "Imagerie et Cervau," Inserm U930, Université Francois-Rabelais, Tours, France.
Hospital Clinic Provincial de Barcelona, Barcelona, Spain.
Oper Neurosurg (Hagerstown). 2018 Nov 1;15(5):557-566. doi: 10.1093/ons/opx288.
Sizing of flow diverters (FDs) stent in the treatment of intracranial aneurysms is a challenging task due to the change of stent length after implantation.
To quantify the size change and assess the error in length prediction in 82 simulated FD deployments.
Eighty-two consecutive patients treated with FDs were retrospectively analyzed. Implanted FD length was measured from angiographic images and compared to the nominal sizes of the implanted device. Length change was obtained by subtracting the nominal length from the real length and dividing by the nominal length. Implanted devices were simulated on 3-dimensional models of each patient. Simulation error was obtained by subtracting real length from simulated length and dividing by the real length of the FD. Subanalysis was done using ANOVA. Statistical significance was set to P < .05, and bootstrap resampling was used.
When assessing the length change of the FD after implantation, changes of 30% in average and up to 80% with reference to the nominal length of the device were observed. The simulation results showed a lower error of 3.52% in average with a maximum of 30%. Paired t-test showed nonsignificant differences between measured and real length (P = .07, with the mean of differences at 0.45 mm, 95% confidence interval [-0.950 0.038]).
Nominal length is not an accurate sizing metric when choosing the size of an FD irrespective of the brand and manufacturer. Good estimation of the final length of the stent after deployment as expressed by an error of 3.5% in average.
由于支架在植入后的长度变化，颅内动脉瘤血流导向装置（FD）支架的尺寸选择是一项具有挑战性的任务。
量化 82 例模拟 FD 展开中的尺寸变化，并评估长度预测中的误差。
回顾性分析 82 例接受 FD 治疗的连续患者。从血管造影图像中测量植入 FD 的长度，并与植入器械的标称尺寸进行比较。长度变化通过从标称长度中减去实际长度，再除以标称长度来获得。对每位患者的 3D 模型进行植入器械模拟。通过从实际长度中减去模拟长度，再除以 FD 的实际长度来获得模拟误差。进行方差分析亚组分析。统计学意义设定为 P<0.05，并使用 bootstrap 重采样。
当评估植入后 FD 的长度变化时，观察到平均变化 30%，最高可达 80%，与器械的标称长度相比。模拟结果显示平均误差较低，为 3.52%，最大为 30%。配对 t 检验显示测量长度与实际长度之间无显著差异（P=0.07，差异均值为 0.45 毫米，95%置信区间[-0.950，0.038]）。
无论品牌和制造商如何，标称长度都不是选择 FD 尺寸的准确指标。平均误差为 3.5%，可以很好地估计支架在展开后的最终长度。
