Sadasivan Chander, Dholakia Ronak, Peeling Lissa, Gölitz Philipp, Doerfler Arnd, Lieber Baruch B, Fiorella David J, Woo Henry H
Department of Neurosurgery, Stony Brook University Medical Center, Stony Brook, USA.
Department of Neuroradiology, University of Erlangen-Nuremberg, Erlangen, Germany.
Interv Neuroradiol. 2019 Dec;25(6):655-663. doi: 10.1177/1591019919860829. Epub 2019 Jul 11.
The recent growth of neuro-endovascular treatment has rekindled interest in the use of angiographic techniques for flow assessment. Aneurysm treatment with flow diverters is particularly amenable to such analysis. We analyze contrast time-density curves - recorded within aneurysms before (pre) and immediately after (post) flow diverter implantation to estimate six-month treatment outcomes.
Fifty-six patients with 65 aneurysms were treated with flow diverters at two institutions. A region of interest was drawn around the aneurysm perimeter in image sequences taken both pre and post angiography, and the temporal variation in grayscale intensity within the aneurysm (time-density curve) was recorded. Eleven parameters were quantified from each time-density curve. Aneurysm occlusion status was recorded six months post treatment. The change in parameters from pre to post treatment was statistically evaluated between aneurysm occluded and non-occluded groups.
Of the 11 parameters, eight were significantly different before and immediately after flow diversion. Considering the entire data set, none of the parameters was statistically different between the occluded and non-occluded groups. However, subgroup analyses showed that four variables were significantly different between the aneurysm occluded and non-occluded groups. The sensitivity of these variables to predict aneurysm occlusion at six months ranged from 60% to 89%, while the specificity ranged from 55% to 70%.
Device-induced intra-aneurysmal flow alterations quantified by simple aneurysmal time-density curves can potentially be used to predict long-term outcomes of flow diversion. Large multi-center studies will be required to confirm these findings. Patient-to-patient variability in coagulation may need to be incorporated for clinically relevant predictive values.
近年来神经血管内治疗的发展重新引发了人们对使用血管造影技术进行血流评估的兴趣。使用血流导向装置治疗动脉瘤尤其适合这种分析。我们分析了在植入血流导向装置之前（术前）和之后立即（术后）在动脉瘤内记录的对比剂时间-密度曲线，以估计六个月的治疗结果。
在两个机构对56例患者的65个动脉瘤进行了血流导向装置治疗。在血管造影术前和术后拍摄的图像序列中，围绕动脉瘤周边绘制感兴趣区域，并记录动脉瘤内灰度强度的时间变化（时间-密度曲线）。从每个时间-密度曲线中量化11个参数。在治疗后六个月记录动脉瘤闭塞状态。对动脉瘤闭塞组和未闭塞组之间治疗前后参数的变化进行统计学评估。
在11个参数中，有8个在血流转向前后有显著差异。考虑整个数据集，闭塞组和未闭塞组之间的参数在统计学上没有差异。然而，亚组分析表明，动脉瘤闭塞组和未闭塞组之间有4个变量有显著差异。这些变量预测六个月时动脉瘤闭塞的敏感性范围为60%至89%，特异性范围为55%至70%。
通过简单的动脉瘤时间-密度曲线量化的装置诱导的动脉瘤内血流改变可能用于预测血流转向的长期结果。需要大型多中心研究来证实这些发现。可能需要纳入患者之间凝血的变异性以获得临床相关的预测值。
