磁共振弥散张量成像研究脑桥梗死后神经纤维华勒变性及临床意义

目的 采用磁共振弥散张量成像(diffusion tensor imanging,DTI)动态观察脑桥梗死后,远离梗死灶的延髓及小脑中脚神经纤维华勒变性及其对患者神经功能恢复的影响.方法 选择单侧脑桥梗死患者14例,以及年龄性别相匹配的健康志愿者14名作对照组.分别在发病第1、4、12周进行DTI检测,并行美国国立卫生研究院卒中评分(National Institutes of Health stroke scale,NIHSS)、简式Fugl-Meyer运动功能评分(Fugl-Meyer motor scale,FM)、共济失调评分(ataxia rating scale,ARS)和Barthel生活指数(Barthel index,BI)评分.结果 与对照组比较,患者梗死灶同侧延髓及双侧小脑中脚的部分弥散各向异性值(fractional anisotropy,FA)从第1周至第12周逐渐减少(延髓梗死同侧FA值:第1周0.43±0.01;第4周0.37±0.02;第12周0.30±0.02,小脑中脚梗死同侧FA值:第1周0.50±0.02;第4周0.43±0.02;第12周0.35±0.04,小脑中脚梗死对侧FA值:第1周0.54±0.02;第4周0.52±0.03;第12周0.47±0.04,t=1.92～28.56,均P＜0.05),而平均弥散量(mean diffusivity,MD)的变化差异却无统计学意义(P＞0.05).在观察期间,患者梗死灶同侧延髓及双侧小脑中脚的FA值减少的百分数绝对值与同期NIHSS及BI变化的百分数绝对值呈负相关(P＜0.05).结论 局灶性脑桥梗死后,同侧延髓及双侧小脑中脚神经纤维的华勒变性持续存在,并且可能阻碍患者神经功能的恢复.     

脑桥梗死后相关神经纤维继发性损害的DTI研究及其意义

目的 本研究应用弥散张量成像(diffusion tensor imaging, DTI)前瞻性观察局灶性脑桥梗死后继发神经纤维顺行性、逆行性变性的动态发展过程,探讨其对患者神经功能恢复的影响.方法 选择单侧脑桥基底部梗死患者14例,以及年龄性别相匹配的健康志愿者14名作对照组.患者分别在发病第1周、第4周和第12周进行DTI检测,对照组只做1次DTI检查.测量脑桥(患者梗死灶所在水平)及近、远端锥体束、双侧小脑中脚的MD和FA值.在每次DTI检测之前进行NIHSS、 FMS和BI评分.结果 与对照组比较,患者梗死灶及其同侧近、远端锥体束纤维、双侧小脑中脚神经纤维的FA值在各个时间点均明显减少(P<0.01);梗死灶的MD在第1周时下降,在第4周及第12周则升高(P<0.01);患者梗死灶同侧近、远端锥体束纤维以及双侧小脑中脚神经纤维的MD在各个时间点均无统计学差别(P>0.05).患者梗死灶同侧近、远端锥体束纤维以及双侧小脑中脚神经纤维的FA值,从第1周至12周随时间延长而逐渐减少(P<0.01), MD却无明显变化(P>0.05).在观察期间,梗死灶同侧近、远端锥体束纤维以及双侧小脑中脚神经纤维的FA值减少的百分数的绝对值与同期NIHSS及FMS变化的百分数的绝对值呈负相关(P<0.05),与BI无明显相关(P>0.05).结论 局灶性脑桥梗死后,可以引起与之发生联系的神经纤维发生顺行性及逆行性继发性变性,这种神经纤维的继发性变性至少在发病后12周内逐渐进展,并可能会延缓患者神经功能的恢复.     

局灶性脑梗死继发逆行性神经纤维变性及其临床意义

目的应用磁共振弥散张量成像(diffusion tensorimaging,DTI)技术前瞻性动态观察皮质下或脑干局灶性脑梗死后,病灶上方继发的神经纤维逆行性变性的过程,探讨其对神经功能恢复的影响。方法选择具有单侧内囊区或脑干的独立病灶的脑梗死患者16例,选择年龄及性别相匹配的健康志愿者16名作为对照组。患者分别在发病的第1周(W1)、第4周(W4)、第12周(W12)进行DTI检测和美国国立卫生研究院卒中评分(national institutes of health stroke scale,NIHSS)、简式Fugl-Meyer运动功能评分法(FM)和Barthel生活指数(Barthel Index,BI)评分。计算半卵园中心的DTI参数和各临床评分在观察期内变化的百分数绝对值,分析两者之间的相关关系。结果与对照组比较,病灶上方半卵园中心的部分弥散各向异性(fractional anisotropy,FA)值在各个时间点均明显减少(患者组W1:(0.43±0.02),W4:(0.39±0.01),W12:(0.33±0.02),分别与对照组比较:(0.46±0.01),P<0.01),而平均弥散量(mean diffusivity,MD)无统计学差异(P>0.05)。患者从W1至W12,半卵园中心FA值减少的百分数的绝对值与NIHSS评分减少百分数的绝对值之间(r=-0.49,P<0.05)及与FM增加百分数的绝对值之间(r=-0.56,P<0.05)呈负相关,与BI变化的百分数的绝对值之间无明显相关(P>0.05)。结论局灶性皮质下脑梗死可引起神经纤维逆行性的继发性变性,而且这种逆行性的神经纤维继发性变性会持续存在并可能阻碍患者神经功能的恢复。     

丘脑梗死后丘脑放射纤维继发变性的磁共振弥散张量成像

目的 应用磁共振弥散张量(diffusion tensor imaging,DTI)技术动态观察局灶性丘脑梗死后丘脑放射纤维的弥散变化,探讨丘脑梗死后,病灶上方的丘脑放射纤维继发性损害的发生发展规律.方法 连续收录首次发病、单侧丘脑梗死患者17例为实验组,选择健康志愿者17例作对照研究.患者分别在发病的第1周(W1)、第4周(W4)和第12周(W12)进行1次DTI检测,对照组进行1次DTI检测.每次DTI检测之前进行美国国立卫生研究院卒中评分(national institute health stroke scale,NIHSS)和Barthel生活指数(BI)以及自订的感觉障碍分级评分(Sensory disturbance rating,SDR)评定.结果梗死灶上方的半卵圆中心部分异向(fractional anisotropy,FA)值随时间延长逐渐减少(W1:0.42±0.02,W2:0.38±0.02,W12:0.34± 0.03,P<0.01),而平均弥散量(mean diffusion,MD)却无明显变化.梗死灶上方的半卵圆中心FA值的变化百分数与NIHSS、和BI的变化百分数无明显相关(P＞0.05),与SDR变化的百分数呈负相关(r＝-0.246,P<0.05).结论 局灶性丘脑梗死可以引起丘脑放射纤维继发性损害,在12周内这种继发性损害逐渐加重,而且还可能阻碍患者感觉功能的恢复.     

脑梗死后继发神经纤维顺行性和逆行性损害的磁共振弥散张量成像

目的应用磁共振弥散张量成像(DTI)技术前瞻性动态观察皮质下局灶性脑梗死后,病灶上、下方远隔部位的神经纤维继发性变化的过程,探讨其与神经功能恢复的意义。方法选择具有单侧大脑中动脉(MCA)供血的皮质下累及内囊的独立病灶脑梗死患者10例,选择年龄性别相匹配的健康志愿者10名作对照研究。患者分别在发病的第(7±2)天(D7)、第(30±3)天(M1)、第(90±3)天(M3)进行DTI检测,并采用美国国立卫生研究院卒中评分(NIHSS)、简式Fugl-Meyer运动功能评分(FM)法和Barthel生活指数(Barthel Index,BI)评定。结果与对照组比较,病灶侧内囊上、下方远隔部位的部分弥散各向异性(FA)值明显减少,而且从D7至M3内囊上方(0.34±0.01和0.28±0.03,P<0.01)、下方(0.42±0.02和0.37±0.06,P<0.01)有逐渐减少趋势,而平均弥散量(MD)却无明显变化。内囊上、下方的FA值均与NIHSS值呈正相关,内囊下方FA值还与Fugl-Meyer运动评分、BI呈负相关。结论局灶性皮质下脑梗死可引起其顺行性和逆行性远隔部位神经纤维的继发性损害,其临床意义尚有待研究。     

DTI态观察脑梗死后颈髓皮质脊髓束继发性损害

目的应用磁共振弥散张量成像(diffusion tensori maging,DTI)动态观察脑梗死后颈髓皮质脊髓束的弥散变化,及其与患者神经功能恢复之间的关系,探讨脑梗死后颈髓皮质脊髓束纤维继发性损害及其意义。方法患者分别在的第1周,第4周以及第12周进行DTI检测,每次MRI检测之前采用NIHSS、简式Fugl-Meyer运动功能评分法(FM)和Barthel生活指数(Barthel Index,BI)评定。分别测量颈髓皮质脊髓束的部分弥散各向异性(fractional anisotropy,FA)值与平均弥散量(mean diffusivity,MD)。结果与对照组比较,患者组病灶对侧颈髓皮质脊髓束FA值在各个时间点都明显低于健康对照组第1周:(0.66±0.01,vs,0.71±0.01,P0.01),第4周(0.61±0.02,vs,0.69±0.01,P0.01),第12周(0.53±0.02,vs,0.69±0.01,P0.01),MD值则无明显差异。患者病灶对侧颈髓皮质脊髓束FA值在观察期内变化的百分数与NIHSS、Fugl-Meyer运动评分变化的百分数呈负相关(P0.05)。结论局灶性脑梗死引起的皮质脊髓束纤维的继发性损害可以延续到颈髓水平,颈髓皮质脊髓束的继发性损害可能延缓患者神经功能的恢复。     

纹状体梗死后黑质继发性损害的弥散张量成像

目的探讨纹状体梗死后黑质继发性损害的发生发展过程及其潜在意义。方法连续收录初次发病、具有单侧基底节区局灶性梗死灶,纹状体明显受累的脑梗死患者11例。招募年龄性别相匹配健康志愿者11名作对照研究。患者分别在发病的第1周(W1)、第4周和第12周(W12)进行常规MRI和弥散张量(diffusion tensorimaging,DTI)检测,以及美国国立卫生研究院卒中评分(national institute health stroke scale,NIHSS)、Barthel生活指数(Barthel Index,BI)评定,在W12对部分有类似于帕金森氏病症状的患者采用帕金森氏病综合评分量表(unifiedParkinson s disease rating scale,UPDRS)的第Ⅲ分量表评价其严重程度。对照组于相同时间间隔进行DTI检测。结果与对照组比较,患者梗死灶同侧黑质的平均弥散量(mean diffusivity,MD)在各个时间点均明显升高:W1(对照组:0.709±0.005,患者组:0.732±0.121,P0.01),W4(对照组:0.710±0.005,患者组:0.776±0.067,P0.01),W12(对照组:0.713±0.005,患者组:0.904±0.112,P0.01);而且随时间延长有逐步升高的趋势。有1例患者出现类似于帕金森氏病的症状,UPDRS的第Ⅲ分量表评分为18分。结论 DTI可以检测到纹状体梗死后黑质继发性损害的程度及其发展过程;黑质的继发性损害可能与患者出现类似于帕金森氏病的症状有关。     

脑梗死后锥体束华勒变性的弥散张量成像

目的 应用弥散张量成像(DTI)探讨脑梗死后锥体束华勒变性(WI))弥散参数的变化规律及其早期变化与神经功能的关系.方法 选取2006年3月至2007年1月收入我院神经内科病房的急性(发病7 d内)脑梗死患者15例,男性13例,女性2例.于发病后7 d内、14 d分别进行DTI检查和美国国立卫生研究院腩卒中评分(NIHSS)、日常生活能力指数(BI)、修正的Rankin评分(mRS)、运动功能指数(MI)等神经功能评分.用西门子Trio 3.0T MR机采集DTI数据,由DTI Studio软件处理分析数据.计算出平均弥散系数(MD)、部分各向异件(FA)、第一本征值(λ1)、第二本征值(λ2)和第三本征值(λ3)的参数图.结果 发病14 d时的神经功能评分,NIHSS:6.93±3.39,BI:45.33±26.01,mRS:4.33±0.90,MI:69.47±60.71.发病14 d时病灶侧与健侧DTI指标比较,从大脑脚到延髓各个感兴趣区,脑桥中部的MD和延髓上部的MD两侧差异无统计学意义,其余病灶侧与健侧差异均有统计学意义.病灶侧的MD较健侧下降,病灶侧的FA较健侧减小,λ1较健侧降低,λ2和λ3较健侧增加.发病后14 d的DTI指标与NIHSS呈负相关(r=-0.613,P=0.015),与BI呈正相关(r=0.530,P=0.042),与MI呈正相关(r=0.543,P=0.036).结论 DTI可以检测脑梗死后第2周的脑桥锥体束WD,其表现为λ1下降、λ2和λ3升高、FA降低,尤其是后者与运动功能障碍相关.     

血清高敏C反应蛋白水平与脑梗死关系的研究

目的探讨血清高敏C反应蛋白(hsCRP)水平与脑梗死病情及预后的关系。方法测定90例急性脑梗死患者入院时血清hsCRP含量,观察梗死灶大小不同、神经功能缺损程度不同时含量变化,应用美国国立卫生研究院卒中量表(NIHSS)及Barthel指数(BI)分别对患者入院时及治疗6个月后进行评分,并将血清hsCRP水平与NIHSS及BI评分进行相关性分析。同时选取80例健康体检人员血清hsCRP含量进行对照。结果脑梗死患者血清hsCRP含量明显高于健康对照组(P<0.01);脑梗死血清hsCRP水平越高,梗死灶越大,神经功能缺损程度越重;患者血清hsCRP水平与入院时NIHSS呈显著正相关(P<0.01),与6个月后BI评分呈显著负相关(P<0.01)。结论血清hsCRP水平是临床评价脑梗死严重程度和预后的一个重要生物学指标。     

磁共振弥散张量及纤维束成像在急性脑梗死的临床应用

目的探讨急性脑梗死病人梗死灶弥散张量的参数变化及对皮质脊髓束的影响,以早期判断病情、评估预后。方法急性脑梗死患者45例,入院及治疗后分别行NIHSS评分记为NIHSS1、NIHSS2,常规MRI、DWI、DTI/DTT检查,分析病灶FA值的变化及与皮质脊髓束的关系。结果①梗死灶FA值降低百分比和NIHSS1相关(r=0.411,P<0.01)。②45例患者中,皮质脊髓束完整(1级)者15例,病灶致使皮质脊髓束受压、移位(2级)者20例,皮质脊髓束中断(3级)者10例。皮质脊髓束的损伤程度与NIHSS2相关(r=0.894,P<0.01)。结论病灶FA值下降越明显,患者病情越重;皮质脊髓束破坏越严重,患者运动功能受损越重,预后越差。     

A prospective study of secondary degeneration following subcortical infarction using diffusion tensor imaging

Background

Secondary degeneration of the pyramidal tract distal to the primary lesion after a stroke has been detected by some studies using diffusion tensor imaging (DTI) but its potential clinical significance and the degeneration of the fibre tract proximal to the primary lesion have received little attention.

Methods

Twelve patients underwent DTI on the 1st, 4th and 12th week following a subcortical infarct involving the posterior limb of the internal capsule, and 12 age and sex matched controls underwent DTI once. The DTI parameters mean diffusivity and fractional anisotropy (FA), and the clinical scores before DTI examination, including the National Institutes of Health Stroke Scale (NIHSS), the Fugl–Meyer (FM) scale and the Barthel index (BI), were assessed. The relations between the per cent changes in DTI parameters and clinical scores were analysed.

Results

From the 1st to the 12th week after stroke onset, FA values decreased (p<0.01, respectively) in the fibre tract above and below the internal capsule, and the NIHSS decreased (p<0.01) but the FM scale and BI increased (p<0.01, respectively) progressively. The per cent reductions in FA value in the fibre tract above and below the internal capsule were negatively correlated with the per cent changes in NIHSS and FM scale (p<0.05, respectively).

Conclusions

Secondary degeneration of the fibre tract proximal and distal to a primary lesion can be detected by DTI clearly and quantitatively and deteriorates with time progressively, which may hamper functional recovery after a subcortical cerebral infarct.Animal experiments and post‐mortem examinations have demonstrated that a focal cerebral infarct can cause secondary degeneration in fibre pathways remote from the primary lesion. Delayed disintegration of such a fibre tract is considered to be Wallerian degeneration (WD), defined as anterograde degeneration of a nerve tract distal to an injury.^1,2,3,4,5 Conventional MRI can detect the ipsilateral cerebral peduncle atrophy during the chronic stage of a focal cortical infarct^6,7,8 but cannot reveal the delayed degeneration in the pyramidal tract on other regions clearly or quantitatively. Diffusion tensor imaging (DTI), which uses diffusion sensitive gradients applied in at least six non‐collinear directions, can determine the diffusivity of every voxel and fully depict tissue diffusion characteristics. DTI has been used to detect and quantify the secondary degeneration in the fibre tract in vivo.^9,10Thomalla et al¹¹ reported that secondary degeneration revealed by DTI occurred in the pyramidal tract distal to the primary lesion from the acute (5 days from onset) to the chronic (288 days) stage in two patients with ischaemic stroke. In some cross sectional studies, fractional anisotropy (FA) values were found to be generally reduced along the pyramidal tract on the infarct side distal to the primary lesion.^9,12,13 After middle cerebral artery territory infarction, lower FA values in the cerebral peduncle were associated with a greater neurological deficit acutely, with worse outcomes 3 months later.¹³ However, to date, no prospective, controlled, contrast enhanced studies have monitored secondary degeneration, and the potential clinical significance of the degeneration distal to the primary lesion has not been confirmed. In addition, only one case report revealed that a pontine infarct can cause retrograde degeneration in the fibre pathway proximal to the primary lesion.¹⁴ However, there has been little research on the retrograde degeneration of the fibre tract after subcortical infarction, and its impact on the patient''s outcome is not well understood.In this study, DTI was used to prospectively quantify and monitor changes in diffusivity in the fibre pathway both proximal and distal to a recent subcortical infarct in 12 patients. The relation between the per cent changes in DTI parameters and clinical scores were analysed.     

脑梗死后早期锥体束华勒氏变性的弥散张量成像

目的 探讨应用弥散张量成像(diffusion tensor imaging,DTI)检测脑梗死后早期锥体束华勒氏变性的可行性.方法 选取起病14 d内的大脑中动脉区脑梗死患者23例,在入院时行MRI与DTI检查.采用工作站之Functool软件,重建出平均弥散系数(mean diffusivity,MD)、各向异性分数(fractional anisotropy,FA)的参数图.通过放置感兴趣区(region of interest,ROI)的方式获得FA和MD值.ROI放置的部位包括:脑梗死区、脑梗死同侧内囊后支前部和大脑脚,以及上述部位对侧相应区域.结果 最早在起病后第3天即可见脑梗死同侧锥体束FA值下降,自起病7 d后所有患者均出现脑梗死同侧锥体束FA下降,与对侧锥体束FA比率为(0.89±0.09),其差异有统计学意义(P<0.05);脑梗死同侧锥体束MD无明显变化,与对侧锥体束MD比率平均为(0.96±0.10),其差异无统计学意义(P>0.05).结论 DTI可以在脑梗死后早期检测到锥体束的华勒氏变性,最早为发病后第3 d.     

Diffusion tensor MRI as a diagnostic tool of upper motor neuron involvement in amyotrophic lateral sclerosis

BACKGROUND: Clinical identification of upper motor neuron (UMN) dysfunction in amyotrophic lateral sclerosis (ALS) is often difficult, particularly early in the course of the disease, or when lower motor neuron (LMN) dysfunction is prominent. Diffusion tensor MR imaging (DTI) can provide unique information on axonal organization by measuring diffusion anisotropy and the directionally independent diffusion. OBJECTIVE: The purpose of this study was to assess water diffusion changes along pyramidal tracts of the brainstem in patients with ALS and to investigate possible correlations between changes of diffusion properties and various clinical parameters. METHODS: We studied 16 patients (M:F=9:7, 50.5+/-12.4 years) with ALS as defined by clinical and electrophysiological examinations. These patients were compared with 11 healthy, age and sex-matched controls (M:F=5:6, 54.5+/-9.9 years). DTI was performed using a single shot SE-EPI with 25 noncollinear diffusion gradient directions (b=1000 s/mm(2)) and with no diffusion gradient on a 3.0-T MR system. RESULTS: By multifactorial ANOVA, the effects of group (patient versus control) and anatomical level on fractional anisotropy (FA) and mean diffusivity (MD) were significant (p<0.001 for both parameters), whereas the effect of side (left versus right) and interactions between factors (group by side and group by anatomical level) were not (p>0.05). In all subjects, FA and MD varied greatly depending on the anatomical level, and FA was highly variable even between contiguous slices in the pons and medulla, whereas relatively constant FA values were noted at the level of the midbrain. Cerebral peduncle was the only area that showed significant differences of diffusion properties between patients and controls (p<0.001 for FA, p=0.001 for MD). Correlation analysis revealed a significant inverse relationship between the FA value and the extent of UMN signs (r=-0.81, p<0.001). CONCLUSIONS: Alteration of diffusion properties in the cerebral peduncle in ALS may reflect pathological changes in structures rather than regional architectural variations of the corticospinal tracts or experimental artifacts.     

定量研究人脑结构DTI T_2-weighted trace图与年龄的关系

目的定量研究不同年龄健康人脑结构扩散张量成像(DTI)的T2-WT参数图的特点及其与年龄的关系。方法健康右利手志愿者58人,年龄22～76岁,按年龄分为青年(≤40岁)组30人,中老年(>40岁)组28人,采集人脑常规MRI及DTI图像,经后处理得到DTI的三种参数图:T2-WT、分数各向异性(FA)及平均扩散系数(MD)图,使用FA图及MD图设置兴趣区,测量人脑10个部位的参数值,定量分析不同年龄组T2-WT参数值的特点及其与年龄的关系。结果青年组T2-WT值在桥脑、大脑脚、内囊前肢、半卵圆中心和豆状核左侧>右侧,P=0.000～0.024,差异有统计学意义。中老年组,半卵圆中心T2-WT值左侧>右侧,P=0.042,差异有统计学意义。两组比较,除侧脑室外,其他部位中老年组的T2-WT值均低于青年组,T2-WT值在桥脑、大脑脚投射纤维、内囊前肢、内囊膝部、内囊后肢和豆状核六个部位与年龄有负相关关系,P=0.000～0.038,差异有统计学意义。结论健康人脑结构T2-WT值在桥脑、大脑脚投射纤维、内囊前肢、内囊膝部、内囊后肢和豆状核与年龄有负相关关系,T2-WT图的左右对称性在中老年人脑表现更明显。     

Retrograde Wallerian degeneration of cranial corticospinal tracts in cervical spinal cord injury patients using diffusion tensor imaging

Diffusion tensor imaging (DTI) has the potential to reveal disruption of white matter microstructure in chronically injured spinal cords. We quantified fractional anisotropy (FA) and mean diffusivity (MD) to demonstrate retrograde Wallerian degeneration (WD) of cranial corticospinal tract (CST) in cervical spinal cord injury (SCI). Twenty-two patients with complete cervical SCI in the chronic stage were studied with DTI along with 13 healthy controls. Mean FA and MD values were computed for midbrain, pons, medulla, posterior limb of internal capsule, and corona radiata. Significant reduction in the mean FA and increase in MD was observed in the cranial CST in patients with SCI compared with controls, suggesting retrograde WD. Statistically significant inverse FA and MD changes were noted in corona radiata, indicating some restoration of spared white matter tracts. Temporal changes in the DTI metrics suggest progressing degeneration in different regions of CST. These spatiotemporal changes in DTI metrics suggest continued WD in injured fibers along with simultaneous reorganization of spared white matter fibers, which may contribute to changing neurological status in chronic SCI patients.     

右利手年轻人脑结构DTI的T_2-weighted trace图定量研究

目的定量研究右利手年轻人人脑结构扩散张量成像(DTI)的T2-weighted trace(T2-WT)参数值的特点,分析其与分数各向异性(FA)、平均扩散系数(MD)的关系。方法健康右利手年轻志愿者30例,男16名,女14名,平均年龄28.2岁,采集脑常规MRI及DTI图像,获取DTI的T2-WT、FA及MD三种后处理参数图:测量人脑13个部位的三种参数值,研究T2-WT参数图左右侧之间的差异,各部位参数值的性别差异,分析其与FA、MD的关系。结果 T2-WT值在桥脑、大脑脚、内囊前肢、半卵圆中心和豆状核双侧不对称,左侧>右侧,P=0.000～0.024,差异有统计学意义;各部位的T2-WT值男女差异无统计学意义,P=0.081～0.967;T2-WT与FA无相关关系,与MD之间有负相关关系,P=0.000。结论右利手年轻人脑结构T2-WT参数存在多个部位的左侧优势,T2-WT参数值男女差别无统计学意义,T2-WT与FA无相关关系,与MD之间有负相关关系。     

Lateral Medullary Syndrome Following Injury of Lateral Vestibulospinal Tract: Diffusion Tensor Imaging Study

BackgroundUnilateral lesions of vestibular nucleus can cause lateral medullary syndrome. Little is known about injury of medial and lateral vestibulospinal tract (VST) after dorsolateral medullary infarct. We investigated injury of the lateral VST in patients with typical central vestibular disorder using diffusion tensor tractography (DTT).MethodsSeven patients with lateral medullary syndrome and ten control subjects were recruited. For the medial VST, we determined seed region of interest (ROI) as medial vestibular nuclei of pons and target ROI on posteromedial medulla. For the lateral VST, the seed ROI was placed on lateral vestibular nuclei of pons, and the target ROI on posterolateral medulla. Fractional anisotropy (FA), mean diffusivity (MD), and tract volume were measured.ResultReconstructed lateral VST on both sides had significantly lower FA values in patients than controls (p<0.05). Tract volume of lateral VST in affected side was significantly lower than unaffected side and control group (p<0.05). However, no DTI parameters of the medial VST differed between patients and controls (p>0.05).ConclusionInjury of the lateral VST was demonstrated in patients with lateral vestibular syndrome following dorsolateral medullary infarct. Analysis of the lateral VST using DTT would be helpful in evaluation of patients with lateral medullary syndrome.