基于高分辨磁共振成像技术的未破裂脑动脉瘤危险分层研究

Aneurysmal subarachnoid hemorrhage (SAH) is one of the most important diseases that threatening human health. Prophylactic treatment is believed as a key treatment to improve the prognosis of aneurysmal SAH. However, considering that not every detected unruptured cerebral aneurysm (UCA) will rupture and if we indiscriminately treat them all, it may result in heavy social and economic burden and cause serious iatrogenic damage because of over treatment. Consequently, idea indication for prophylactic treatment should be restricted to high risk UCAs. However, there is still no idea scientific method to effectively detect high risk UCAs. Geometrical morphology of aneurysm and its parent artery were mostly used to judge the growth and rupture risk of unstable UCAs in clinical. Recently, many histopathological and molecular biological studies focused on aneurysm generation, development and rupture have proved that inflammation reaction within aneurysm wall and hemodynamic action may play important roles in aneurysm rupture. In this project, we are trying to provide risk stratification for UCAs in micro and macro levels based on aneurysm rupture related geometric, hemodynamic and molecular imaging studies, using high resolution magnetic resonance scan and imaging techniques. The findings of this project may be of great helpful to raise recognition of high-risk UCAs and precisely master the therapy indication to reduce the rate of mortality and morbidity for UCAs.

动脉瘤性蛛网膜下腔出血（SAH）是严重危害人类健康的重要疾病之一。预防性治疗脑动脉瘤降低破裂风险被认为是改善动脉瘤性SAH预后的关键。然而，并非所有检出的未破裂脑动脉瘤（UCAs）均会发生破裂。如对这些动脉瘤不加选择治疗，将会因过度治疗而产生沉重的社会经济负担以及伴随治疗而可能发生严重的医源性损害。目前，识别高危UCAs尚缺乏科学的检测手段。脑动脉瘤及其载瘤动脉的几何形态学特征一直以来被临床用于预判不稳定动脉瘤生长和破裂的风险；同时脑动脉瘤发生、发展和破裂的病理生理以及分子生物学研究均表明动脉瘤壁炎性反应和血流动力学与动脉瘤破裂密切相关。本课题基于高分辨磁共振成像技术，以脑动脉瘤破裂相关的分子生物学和几何学为基础，利用分子影像学及计算机流体力学分析，从微观分子水平及宏观结构上对UCAs进行危险分层，以期提高对高危UCAs的认识，准确把握UCAs破裂前的早期干预指证，降低UCAs病死率。

针对脑动脉瘤性破裂出血可严重危害人类健康，识别高危未破裂脑动脉瘤（UCAs）尚缺乏科学的检测手段，过度治疗易于产生沉重的社会经济负担以及医源性损害的临床问题，课题组基于高分辨磁共振成像技术，采用形态学以及计算机流体力学分析，对UCAs进行危险分层，可提高对高危UCAs的认识，准确把握UCAs破裂前的早期干预指证，降低UCAs病死率。具体研究成果如下：1）完成了未破裂脑动脉瘤患者在线随访数据库的搭建。已经入组996例未破裂脑动脉瘤病例，完成入组患者数据库信息输入，录入信息包括病例基础信息、动脉瘤形态学信息和影像学随访信息；2）未破裂侧壁脑动脉瘤在3D-TOF-MRA筛查过程中的诊断准确性一直缺乏客观参数指标，本研究中，项目组证实通过动脉瘤流出角参数的测量，可以明显提高3D-TOF-MRA对于侧壁动脉瘤诊断的准确性，进而提高3D-TOF-MRA临床筛查未破裂脑动脉瘤的可靠性；3）针对目前3D-TOF-MRA诊断小动脉瘤阳性率越来越高，但是其与动脉圆锥区分困难的临床难题，通过3D-TOF-MRA动脉瘤流出角度测量，用于鉴别诊断小的侧壁动脉瘤和动脉圆锥；4）通过无创的3D-TOF-MRA影像学方法，对临床急性蛛网膜下腔出血患者脑动脉瘤检出，瘤体以及载瘤动脉形态学精确显示，与有创动脉插管造影高度符合；5）通过基于动脉瘤和载瘤动脉的形态学分析，发现能够预测前交通动脉瘤破裂的高危因素是年龄<65岁和动脉瘤最大径>5mm，其中大脑前动脉A1缺如或者发育不全则是预测前交通动脉瘤生长的有效预测因素；6）通过长期的影像学随访证实支架辅助栓塞颈内动脉C6段脑动脉瘤具有较好的远期瘤腔闭塞率和手术安全性。