摘要
目的 :通过动物模型 ,从检查时间和影像质量两方面探讨肢体枪击伤行MRI检查的合理扫描方案。方法 :手枪致伤 8条成年杂种狗后腿 ,用 0 .5TMR分别在伤后 5、2 4、48和 72h行双后腿横轴位、冠状位与矢状位的T1 WI(SE)、T2 W (FSE)、PDW (FSE)和STIR(FSEIR) ,最后经静脉注入钆喷酸葡胺行T1 W (SE)。结果 :适当调整常规扫描参数和扫描的范围 ,单次扫描时间 3～ 5min内都能获得满意的图像。T2 WI结合增强后的T1 WI能清楚地区分原发弹道、挫伤区与震荡区等病理改变。STIR对液体信号的表现上优于T2 ,但在解剖结构的显示上比T2 差 ;PDWI上挫伤区显示欠清 ,且伤道内液体与震荡区信号差别不明显 ;平扫T1 在反映病理改变上价值不大。平行于原发伤道的冠状位图像能清晰显示各病理区的信号梯度改变 ;垂直于弹道的矢状位图像上可观察到肌肉的撕裂伤和沿伤道的不规则线条样或点片状挫伤区异常信号。横轴位能清楚显示各肌群间的关系 ,但完成震荡区的扫描需耗费成倍的时间。结论 :在日常工作的扫描参数基础上 ,适当调整扫描范围与参数即可在短时间内获得准确反映肢体枪击伤后组织损伤情况的MR图像。T2 WI和增强T1 WI序列为必须扫描序列。
Objective:To investigate the reasonable scanning program of MR in the examination of limb gunshot wound regarding the scanning time and imaging quality in animal models.Methods:The hind legs of eight mongrel dogs shot with handgun were performed 0.5T MR scanning at 5h,24h,48h and 72h after injury respectively. MR sequences included axial,coronal and sagittal T 1 weighted SE,T 2 weighted FSE,PD weighted FSE,STIR FSEIR and Gd DTPA enhanced T 1 weighted SE.Results:After proper adjustment of scanning parameters, satisfactory MR images were obtained during three to five minutes in per sequence.T 2 weighted together with contrast enhanced T 1 weighted sequences demonstrated clearly the permanent tract, contusion zone and concussion zone.STIR images depicted water or fluid signal better than T 2 weighted images, but worse in anatomic structure.Signal intensity difference between the liquid of tract and the concussion was little and the contusion zone was not demonstrated clearly on PD weighted images.T 1 weighted images were not vanualle.Coronal images parallel to the tract displayed clearly the transformation among the permanent tract,contusion zone and concussion zone.Laceration of muscles and irregular line,spot or patchy contusion zone around the tract were depicted in sagittal images. Though axial images could clearly display the relation of muscles, it would take double time to finish the scanning of concussion zone. Conclusion:Accurate images about the damage of limb gunshot wound can be yielded in a short time by adjusting the routine parameters and the scanning field properly.T 2 weighted and contrast enhanced T 1 weighted sequences are necessary in such examination.In addition, axial and imaging plane which parallels to the wound tract are valuable to show the anatomy and signal transformation within the pathological area.
出处
《放射学实践》
2004年第3期179-182,共4页
Radiologic Practice
