【摘要】 目的 根据头颅MRI对脑桥梗死病灶的定位,结合脑桥的解剖学特点,探讨脑桥梗死临床表现的特点。方法 50例急性脑桥梗死均行头颅MRI检查,并对其病灶位置分布、神经系统体征、神经功能缺损程度 (MRS评分)等指标进行分析。结果 按头颅MRI横轴位上的病灶位置,50例脑桥梗死病例中:腹内侧梗死占48%,腹外侧梗死占32%,被盖部梗死占12%,双侧梗死占8%。在临床表现特点上,腹内、外侧梗死多表现为病灶对侧肢体偏瘫、中枢性面瘫以及构音障碍,同时伴或不伴肢体共济失调;脑桥被盖部梗死主要表现为脑神经瘫痪及感觉障碍;双侧脑桥梗死则往往表现为假性延髓性麻痹、双侧肢体运动障碍。腹内、外侧梗死起病后30 d MRS评分值较入院时明显改善(P<0.01),双侧脑桥梗死MRS评分值较其余各组高。结论 脑桥梗死病灶多位于腹侧,且多表现为病灶对侧肢体瘫痪、中枢性面瘫以及构音障碍;脑桥梗死预后总体较好,不同梗死部位范围影响神经功能缺失程度。
【关键词】 脑桥梗死;临床表现;磁共振成像
【Abstract】 Objective To study the clinical features of pontine infarction with the results of MRI and the anatomy feature. Methods We observed 50 acute pontine infarctions and paid attention to the lesion distribution, nerve system signs and general disability status.Results Based on the lesion distribution, 50 pontine infarction cases could be classified into ventromedial(48%), ventrolateral(32%), tegmental(12%) and bilateral infarctions(8%). Ventromedial and ventrolateral infarcts lead to contralateral brachiocrural hemiparesis, central facial paresis and dysathria, also with or without brachiocrural ataxia. Isolated tegmental infarcts were associated to cranial nerve palsy and sense disturbances, with mild motor deficits. Bilateral infarction involved the bilateral pyramidal tracts and tegmentum, represents pseudobulbar palsy and bilateral motor deficits. General disability status and outcome: MRS score of 30 d after onset was distinctly better than admission in ventral groups(P<0.01), bilateral group had the worst MRS score. Conclusion The ventral lesions is most common for pontine infarctions. Pontine infarctions often present as contralateral brachiocrural hemiparesis, central facial paresis and dysathria. The degree of disability status is corresponding to the leision site.
在表1中我们比较了不同部位脑桥梗死的体征,发现构音障碍与中枢性面瘫在被盖部梗死中的出现率明显小于其他脑桥梗死类型,这是由于梗死灶避开了位于脑桥基底部的皮质核束。腹内侧梗死肢体偏瘫以上肢重于下肢多见,而腹外侧梗死则相反。这多与皮质脊髓束上、下肢纤维的排列有关:支配上肢的纤维位于前内侧,而下肢纤维位于相对后外侧[16]。表2比较了4组的MRS评分:腹内、外侧梗死起病后30 d MRS评分值较入院时均有明显改善。双侧脑桥梗死累及双侧锥体束与被盖结构,MRS评分值最高。被盖部梗死多表现为颅神经症状,锥体束累及较轻,因而MRS评分值低于其他组。有文献表明:脑桥梗死远期存活率高[17];梗死部位、范围不同以致锥体束受累程度存在差异,从而影响脑桥梗死的预后[18]。
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