摘要
第一部分 无症状性脑梗死的临床意义
1．“健康”老年人中无症状性脑梗死的调查
目的：了解无症状性脑梗死(SCI)在老年人中的发生率。资料和方法：109例2001年9月-2002年12月在华山医院神经科和老年科就诊的门诊患者，平均年龄73±6.6岁，所有对象均无明确神经系统器质性疾病史。根据MRI FLAIR序列上SCI的部位、大小和数目分别观察不同程度皮质下深部白质高信号(SDWMH)、脑室旁高信号(PVH)和由二者组成的混合性损害的发生率。结果：109例患者中89例(81.7％)有不同程度的SDWMH，其中Ⅰ级者31例，Ⅱ级者28例，Ⅲ级者30例。93例(85.3％)有不同程度的PVH，其中Ⅰ级者17例，Ⅱ级者37例，Ⅲ级者39例。99例(90.8％)有不同程度的混合性损害，其中轻度者25例，中度者35例，重度者39例。
2．无症状性脑梗死对首次缺血性中风患者临床及预后的影响
目的：了解SCI在首次缺血性中风患者中的发生率，相关危险因素，及其对中风患者预后的影响。设计：回顾性前瞻研究。资料和方法：228例1999年9月-2001年10月在华山医院神经内科住院的首次急性缺血性中风患者。排除有明确中风史和痴呆史者。根据MRI FLAIR序列上SCI的部位、大小和数目将患者分成四组：正常组(无SCI)，轻度组(伴轻度SCI)，中度组(伴中度SCI)，重度组(伴重度SCI)。根据MRI弥散加权成像结果鉴别新鲜梗死灶的部位和大小。结果：228例患者中，无SCI者31例，197例(86.4％)有不同程度的SCI，其中轻度者69例，中度者59例，重度者69例。Logistic回归分析表明年龄(P=0.0001)和血压控制不佳(P=0.0122)是SCI的独立危险因素。SCI越严重，深部白质区新鲜梗死灶越多(P=0.020)；但不同程度SCI间梗死灶大小无统计学差异(P=0.82)。平均随访时间24个月。随访期间11例患者失访。生存分析表明，SCI越严重，中风复发率越高(P=0.0001)。四组中出院后3年中风复发率分别为：正常组3.23％，7.83％，7.83％；轻度组3.23％，3.23％，9.33％；中度组9.42％，16.73％，16.73％；重度组15.85％，30.21％，43.65％。Cox风险模型显示SCI的严重程度(P=0.001)，
复旦大学博士研究生毕业论文
出院后规律服用抗血小板聚集药(P=0.037)及出院后高血压控制情况(P=0.045)与
中风复发率密切相关。生存分析还表明，scl越严重，生存率越低(P=0.0068)。
四组中出院后3年生存率分别为:正常组%.77%，92.17%，92.17%;轻度组
96，82%，96.82%，91.98%;中度组91.67%，91.67%，83.73%;重度组87.54%，
78.78%，75.58%。但Cox风险模型分析，没有发现SCI的严重性与生存率(p=0.054)
之间有显著性差异。结论:SCI在“正常”老年人和首次缺血性中风患者中有较
高的发生频率，年龄和血压控制不佳是SCI的独立危险因素。SCI的严重性不仅
会影响中风部位，且对中风患者的预后，特别是中风复发率有重要影响。
Part I Clinical Significance of Silent Cerebral Infarction
1. Silent cerebral infarction in the neurologically nondiseased elderly
Purpose: To investigate the frequency of silent cerebral infarction (SCI) in the neurologically nondiseased elderly subjects. Material and methods: A total of 109 elderly subjects(mean age 73±6.6 years) were collected from neurological and geriatric clinics of Huanshan hospital from September 2001 to December 2002. All were free from neurological deficit or intellegence dysfunction. Frequency and extent of SCI on FLAIR sequence of MRI (1.5T) were rated separately using Fazekas scale in subcortical white matter and periventricular areas. Results: A total of 89 (81.7%) cases had subcortical white matter hyperintensity(SDWMH). 31 cases had mild, 28 cases had moderate, and 30 cases had severe grade lesions. A total of 93 (85.3%) cases had periventricular hyperintensity(PVH). 17 cases had mild, 37 cases had moderate, and 39 cases had severe grade lesions, A total of 99 (90.8%) cases had SDWMH or PVH. 25 cases had mild, 35 cases had moderate, and 39 cases had severe grade lesions .
2. The effects of silent cerebral infarction on clinical manifestation and prognosis in
patients with first-ever ischemic stroke
Purpose: To investigate the frequency of SCI on MRI, associated factors, and the effects on clinical manifestation and prognosis in patients with first-ever ischemic stroke. Design: Retrospective cohort study. Patients and methods: We studied all patients hospitalized with a diagnosis of first acute cerebral infarction from September 1999 to October 2001. A total of 228 consecutive patients who had no previous history of either stroke or obvious dementia before their index stroke were enrolled in this study. All patients were divided into four groups (normal, mild, moderate, and severe group) according to the localization, size, and numbers of SCI on fluid-attenuated inversion recovery (FLAIR) sequence of MRI. Diffusion-weighted
MRI (DWI) was used to evaluate the localization, size of new lesions. Results: MRI showed that a total of 197 patients (86.4%) had SCI. 69 cases had mild, 59 cases had moderate, and 69 cases had severe grade lesions among them. Logistic regression analysis showed the factors independently associated with SCI to be age (the average age was 50.5±5.2, 66.3±6.7, 71.0±5.9, 75.9±7.1 years old in normal, mild, moderate, and severe group, respectively.) (P=0.0001), and control of hypertension (P=0.0122). The extent of SCI was strongly associated with the localization of new lesions on DWI (new lesions occurred in deep white matter were 2/31, 12/69, 12/59, 29/69, in normal, mild, moderate, and severe group, respectively.)(P=0.020), but not with the size. Mean follow-up time was 24 months. 11 patients were lost to follow-up at the end of the study. Life table analysis revealed that the recurrent stroke rate was significantly higher in patients with severe SCI than in those with mild or without SCI (the recurrent strok
e rates at 1,2, 3 years out of hospital were 3.23%, 7.83%, 7.83% in normal group; 3.23%, 3.23%, 9.33% in mild group; 9.42%, 16.73%, 16.73% in moderate group; and 15.85%, 30.21%, 43.65% in severe group.) (P=0.0001). Cox proportional hazards model showed predictive factors for recurrent stroke rate were SCI (P=0.001), sustained antiplatelet agents (P=0.037), and hypertension control (P=0.045). The extent of SCI was also significantly associated with the survival rate (the survival rate at 1, 2, 3 years out of hospital were 96.77%, 92.17%, 92.17% in normal group; 96.82%, 96.82%, 91.98% in mild group; 91.67%, 91.67%, 83.73% in moderate group; 87.54%, 78.78%, 75.58% in severe group.)( P=0.0068). But Cox proportional hazards model did not find SCI as a predictive factor for survival rate (P=0.084). Conclusions: This study shows that a high frequency of SCI is found in neurologically nondiseased elderly and patients with first-ever ischemic stroke, the independent risk factors for SCI are age and hypertension contr
ol. SCI effects
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