功能磁共振成像与弥散张量成像联合监测视觉通路异常在高压氧治疗前后的结构及功能变化

Functional magnetic resonance imaging plus diffusion tensor imaging for monitoring function and structure of abnormal visual system after hyperbaric oxygen therapy

目的:联合应用血氧依赖功能磁共振成像(BOLD-fMRI)和弥散张量成像技术评价视觉通路异常高压氧患者在康复过程中脑功能和解剖结构的重组特点。方法:①临床资料:选择2006-01/2007-05解放军南京军区福州总医院收治的因视觉通路病变致单侧或双侧视觉障碍的16例患者为病变组,均接受2个标准大气压高压氧治疗3个疗程。以性别、年龄与病变组大致匹配的正常视力者12例作为正常对照组。②磁共振扫描及分析:两组以相同条件,采用黑白棋盘格变化刺激双眼,应用Signa xcite HD 1.5T双梯度16通道磁共振成像系统进行测试。BOLD-fMRI数据处理采用AFNI软件包进行,弥散张量成像应用日本东京大学影像计算和分析实验室开发的Volume-one 1.64下的dTV.II.R1软件进行数据处理。③观察指标:病变组高压氧干预前后BOLD-fMRI激活体数和弥散张量成像表现,并与正常对照组比较。结果:28例受试者均进入结果分析。①BOLD-fMRI激活体数值:病变组高压氧治疗前视皮质激活体数低于正常对照组(P<0.01),高压氧治疗后视皮质激活体数与正常对照组比较差异不显著(P>0.05),但高于高压氧治疗前(P<0.05)。②弥散张量成像示视放射部分各向异性值:病变组高压氧治疗前部分各向异性值低于正常对照组(P<0.05),高压氧治疗后与正常对照组比较差异不显著(P>0.05),且显著高于高压氧治疗前(P<0.05)。病变组中的6例视神经病变患者视放射显示完整,康复前后的视放射部分各向异性值与正常对照组比较无显著性差异(P>0.05),10例枕叶视中枢病变患者视放射纤维部分中断,视放射各向异性值低于视神经病变患者(P<0.05)。结论:BOLD-fMRI联合弥散张量成像能从功能和结构方面探讨视觉通路病变的发生、发展及康复过程,为脑功能的康复提供较为可靠的治疗依据。

AIM： To study recombination characters of brain function and structure in patients with abnormal visual system during rehabilitative treatment of hyperbaric oxygen （HBO） by the combined use of blood oxygenation level dependent functional magnetic resonance imaging （BOLK-fMRI） and diffusion tensor imaging （DTI）. METHODS： （1）Sixteen patients with lateral or bilateral visual dysfunction were selected from Fuzhou General Hospital of Nanjing Military Area Command of Chinese PLA between January 2006 and May 2007, as study group, and they received HBO treatment of 2 standard atmosphere pressures by 3 courses. While 12 healthy subjects who well matched the patients in gender, age and lesion were taken as control group. （2）All the subjects were stimulated by the black and white checkerboard on both eyes, and tested with Signa Excite HD 1.5T 16-tunnel MRI system. BOLD-fMRI data was processed by using AFNI software, and DTI was performed by using Volume-one 1.64 dTV.Ⅱ.R1 software, which was developed by the Image Computation and Analysis Laboratory in the University of Tokyo. （3）The study group were examined with fMRI and DTI before and after HBO treatment, and were compared with the control group. RESULTS： All of 28 subjects were involved in the result analysis.（1）Results of BOLD-fMRI： Before HBO treatment, the visual cortexs of 16 patients was significantly lower than that of 12 healthy subjects （P 〈 0.01）. After HBO treatment, differences of double visual cortex voxel were insignificant between the two groups （P 〉 0.05）, but still was higher than that before treatment （P 〈 0.05）.（2）Results of DTI： The anisotropic values of 16 patients pre-rehabilitative treatment were lower than that of 12 healthy subjects （P 〈 0.05）, and compared with control group, the differences of both groups were not significant post-treatment （P 〉 0.05）, which was significantly higher than that before treatment （P 〈 0.05）. The anisotropic values of 6 patients with optic nerve lesions were intact. Compared with control group, differences of both groups were no significant before and after treatment （P 〉 0.05）. The optic radial fibers were interrupted in 10 patients with cerebral occipital lobes lesions, in whom the anisotropic values were lower compared with the optic nerve lesions patients （P 〈 0.05）. CONCLUSION： Combined uses of BOLD-fMRI and DTI, which investigate the development of rehabilitative process of patients with abnormal visual system in terms of function and structure, can provide the reliable evidences for the rehabilitation of brain function.