MR梯度回波T2^＊WI检出脑微出血

目的：MR梯度回波T2^＊WI可检出无症状性脑微出血，本研究旨在探讨脑微出血的发生率、部位以及与高血压、脑卒中、脑室周围白质高信号的相关性。方法：在1年时间内共有375例患者在常规MRI／序列的基础上加扫T2^＊加权序列，排除了存在脑血管畸形出血、颅内占位、外伤、手术史等病例，共有324例进行分析处理。结果：脑微出血37例，总的发生率为11．4％，尤其位于基底节／放射冠（n=22）、丘脑（n=15）、小脑（n=14）和脑叶区域（n=15），脑微出血主要见于存在脑中风史病例，与年龄、高血压、脑白质疏松症（脑室周围白质高信号）存在相关性（P〈0．001）。在2年多的影像学随访过程中，共发现2例（5．4％）出现新鲜脑出血。结论：MR T2^＊加权像可用于检出脑微出血，其发生提示存在脑微小血管病变，存在继发出血的可能性，建议对于60岁以上的老年人尤其是存在脑中风的病例，MR T2^＊加权应作为常规扫描序列。

Cerebral microbleeds detected on T2*-weighted gradient-echo MR images

Objective：T2^＊ -weighted gradient-echo MR imaging can be used to detect silent cerebral microbleeds. We investigated the incidence and location of microbleeds and the correlation with age, stroke and white matter hypefintensity .Methods：The study population consisted of 375 patients who underwent brain routine MR sequence and T2^＊ -weighted gradient-echo sequence was performed during 1 year. The patients with intraeerebral hemorrhages due to vascular malformations, neoplasms, trauma, or intraeranial surgery were excluded; 324 cases were analyzed. Results：The overall incidence of microbleeds was 11.4 %, predomlnandy in the basal ganglia/corona radiata （n = 22）, thalamus （n = 15）, cerebellum（n = 14） and lobar regions （n = 15）. Mierobleeds can be seen the patients with stoke history. Microbleeds had the significant correlation with advancing age, hypertension, and leukoaraiosis（prominent white matter hyperinteasity） （ P 〈 0.001 ）. Among 37 patients with microbleeds who could be madical imaging followed up more than 2 years, two（5.4% ） had new hemorrhagic stoke. Conclusion： T2^＊-weighted gradient-echo MR imaging can be used to detect silent cerebral miembleeds. The presence of micmbleeds may be a direct maker of advancing small-vessel diseases, and may have a risk of bleeding. We suggest that patients, who are older than 60 years, espacially and had a stroke history, should be routinely examined with T2 ^＊ -weighted gradient-echo MRI.