高清磁共振研究基底动脉粥样硬化狭窄重构模式在脑桥旁正中梗死中的应用

目的 应用3.0T高分辨磁共振成像（high resolution magnetic resonance imaging，HRMRI）探讨脑桥旁正中梗死（paramedian pontine infarction，PPI）患者基底动脉管壁特征及重构模式。方法 连续入组孤立脑桥旁正中梗死患者30例，行头颅磁共振平扫及头颅磁共振血管成像（magnetic resonance angiography，MRA）检查，并用3.0T HRMRI对基底动脉检查，测量管壁特征并计算重构指数（remodeling index，RI）（最窄处血管面积/参考处血管面积）。RI≤0.95为阴性重构，RI 在0.95～1.05之间为无重构，RI≥1.05为阳性重构，比较阴性重构和阳性重构的斑块面积、斑块负荷等特点。结果 30例患者在MRA上共发现9例有基底动脉狭窄，21例显示管腔正常，而在HRMRI可发现25例患者有基底动脉粥样硬化性斑块，并可见斑块位于脑桥旁正中梗死责任血管的穿支动脉口。对HRMRI上发现有动脉粥样斑块的25例患者计算RI，其中阴性重构8例，无重构6例，阳性重构11例，比较两组数据，阳性重构组的斑块面积（8.17±4.7）mm2及斑块负荷（29.07±15.03）%均大于阴性重构组的斑块面积（1.08±1.89）mm2及斑块负荷（3.96±6.76）%，差异具有显著性。结论 HRMRI有助于缺血性卒中的病因学分型并评估病变的RI。脑桥旁正中梗死患者基底动脉阴性重构与阳性重构同样常见，阳性重构常合并较大的动脉粥样硬化斑块，且斑块面积及斑块负荷均大于阴性重构。

Remodeling Pattern of Basilar Artery Atherosclerosis in Paramedian Pontine Infarction:A 3.0T High Resolution Magnetic Resonance Imaging Study

Objective To investigate the properties and remodeling pattern of basilar artery atherosclerosis in paramedian pontine infarction （PPI） with 3.0T high-resolution magnetic resonance imaging （HRMRI）. Methods Thirty consecutive patients with acute paramedian pontine infarction were enrolled from January 2011 to December 2012, all are detected by conventional magnetic resonance imaging （MRI） and magnetic resonance angiography （MRA）, and HRMRI was performed on the target segment by using a 3.0T MR scanner. Remodeling index （RI） was calculated as vessel area at maximal lumen narrowing （MLN）/reference vessel area. RI≤0.95 was deifned as negative remodeling （NR）, 0.95﹤RI﹤1.05 as intermediate remodeling （IR）, and RI≥1.05 as positive remodeling （PR）, wall characteristics were compared between the NR and PR group. Results In 30 patients, 9 arteries were shown stenosis, 21 arteries were shown normal on MRA, while HRMRI detected 25 arteries with plaque, and the basilar artery （BA） plaques at or near the origin of the penetrating artery. Analyze the 25 patients, NR was found in 8 patients, IR in 6 patients, and PR in 11 patients. At MLN sites, compared with lesions with NR, lesions with PR had greater plaque area （[8.17±4.7]mm2 vs [1.08±1.89]mm2, P﹤0.01）, and a greater percent plaque burden （[29.07±15.03]%vs [3.96±6.76]%, P﹤0.01）. Conclusion HRMRI can help assess subtypes of ischemic stroke and the remodeling pattern of BA atherosclerosis. Etiology of PPI is the BA plaque blocking the penetrating artery. In patients with PPI, NR and PR lesions are some frequently observed, and PR lesions have a greater wall area and plaque burden than NR lesions.