磁共振弥散张量成像在基底节区高血压脑出血致皮质脊髓束损伤中的应用研究

Diffusion tensor imaging in evaluating the injury of corticospinal tract in patients with hypertensive basal ganglia hemorrhage

目的 探讨磁共振弥散张量成像（DTI）技术评价基底节区高血压脑出血（HICH）患者皮质脊髓束（CST）受损程度的意义及其与肌力恢复的关系.方法 徐州医学院附属医院神经外科自2006年11月至2009年5月行小骨窗开颅血肿清除术治疗单侧基底节区HICH患者35例,术后10 d应用3.0T磁共振DTI技术检测患者和10例健康志愿者CST,应用Functool软件进行图像分析观察CST损伤程度,HICH患者康复治疗2月后采用Brunnstrom标准进行肢体肌力检查,分析CST损伤程度与肢体肌力的相关性.结果 10例健康志愿者CST显示清晰.35例HICH患者CST受损的模式有3种：纤维束显示达正常侧的2/3或相仿（11例）,患者肢体肌力恢复最好;纤维束显示小于正常侧的2/3（18例）,患者肢体肌力恢复较好;纤维柬显示小于正常侧的1/3（6例）,患者肢体肌力恢复最差.CST受损患者患侧的FA值均较健侧降低,差异有统计学意义（P〈0.05）.3种模式CST损伤患者患侧的FA值、肢体肌力不同,差异均有统计学意义（P=0.000）.患者CST损伤程度与肌力恢复水平存在负相关关系（r=0.931,P=0.000）.结论 应用磁共振DTI技术可显示脑内白质纤维束的走形及分布,能够早期检测HICH患者CST的损伤程度,对患者肢体运动功能损伤的评估、判断预后有重要的临床意义.

Objective To investigate the value of diffusion tensor imaging （DTI） in evaluating the injury of corticospinal tract （CST）, including the motor dysfunction and the integrity of CST, in patients with hypertensive intracerebral hemorrhage （HICH）, and explore the relation between DTI results and the recovery of myodynamia. Methods Clinical data of 10 healthy volunteers and 35 patients with HICH, admitted to our hospital and performed evacuation of hematoma from November 2006 to May 2009, were retrospectively analyzed; DTI by using a 3.0T MR canner were chosen on them and the imaging was analyzed by Functool software. The changes of directionality and integrity of SCT were analyzed on fractional anisotropic （FA） map, color-coded directional map, and three-dimensional white matter tractography. Myodynamic examination at Brunnstrom standard 2 months after rehabilitation nursing was performed in these patients. The correlation between the injured degree of CST and the recovery of myodynamia was analyzed. Results Fiber tractography derived from DTI was consistent with known white matter fiber anatomy in 10 healthy volunteers. Three patterns of corticospinal tract involvement were identified in 35 patients： the intact one in 11 patients （the ipsilateral corticospinal tract was almost the same as contralateral corticospinal tract）, the partially damaged one in 18 patients （the ipsilateral corticospinal tract was less than 2/3 but larger than 1/3 contralateral corticospinal tract） and the ahnost completely damaged one in 6 patients （the ipsilateral corticospinal tract was less than 1/3 contralateral corticospinal tract）. Different pattern had totally different clinical outcome and the intact one had a full recovery. The ipsilateral corticospinal tract showed significantly lower Brunnstrom scores of the upper extremities than the ipsilateral one （P〈0.05）; the Brunnstorm scores and the value of myodynamia among the 3 patterns were statistically different （P〈0.05）. The recovery of motor function was negatively correlated to the injured degree of CST （1=-0.931, P=-0.000）. Conclusion The DTI, offering the optimal visualization of white matter tracts can detect the injured degree of the corticospinal tracts and predicate the prognosis to some extent, thus, early evaluation of corticospinal tract injury based on DT1 can provide predictive value for motor functional outcome in patients with HICH.