皮质下缺血性血管性痴呆患者大脑联络纤维弥散张量成像研究

目的应用磁共振弥散张量成像(DTI)技术,研究皮质下缺血性血管性痴呆(SIVD)患者脑白质联络纤维变化的特点,以探讨弥散张量成像在诊断SIVD患者中的诊断价值。方法对60例SIVD患者和45例年龄匹配的非痴呆对照者,应用简易智能状态检查量表(MMSE)、蒙特利尔认知测评量表(Mo CA)及临床痴呆量表(CDR)进行认知功能评估;用全脑磁共振DTI技术,测量上纵束、下额枕束(额部、额颞部和颞部)、胼胝体膝部和压部和扣带束多个感兴趣区的各向异性分数(FA)值和表观弥散系数(ADC)值。结果与对照组比较,SIVD组双侧下额枕束、双侧扣带束、左侧上额枕束和胼胝体膝部FA值明显下降,ADC值明显升高,差异有统计学意义(均P<0.05),右侧上额枕束和胼胝体压部的FA值和ADC值差异无统计学意义(P>0.05)。结论 SIVD患者多个感兴趣区的DTI改变证明联络纤维损伤明显;全脑DTI研究是SIVD患者敏感可靠的技术方法,有助于理解SIVD患者的认知功能与联络纤维损害的关系。     

磁共振弥散张量成像对预测皮质下缺血性血管性痴呆患者认知功能障碍的价值

目的应用磁共振弥散张量成像(DTI)技术,探讨皮质下缺血性血管性痴呆(SIVD)患者不同联络纤维感兴趣区弥散张量参数改变与认知功能的关系。方法对60例SIVD患者和40例年龄匹配的非痴呆对照者,采用测定感兴趣区弥散张量参数的方法,比较其纤维束完整性差异及与神经心理学量表的关系。结果 (1)与对照组比较,SIVD组双侧下额枕束、双侧扣带束、左侧上纵束和胼胝体膝部的FA值显著下降及ADC值显著升高;(2)双侧额叶前部皮质下白质FA值与MMSE及Mo CA评分呈明显正相关;(3)双侧海马区、双侧扣带束的FA值与MMSE评分呈明显正相关。结论不同脑区的弥散张量参数变化特点有助于SIVD患者认知功能障碍的早期预测。     

磁共振弥散张量成像对阿尔茨海默病脑白质损害的评估及鉴别价值

目的：应用MR弥散张量成像（DTI）观察阿尔茨海默病（AD）患者脑白质纤维束完整性。方法：健康老年志愿者为对照组（NC）组、遗忘型轻度认知障碍（aMCI）组、AD组和皮质下缺血性血管性痴呆（SIVD）组各20例,行常规MRI和DTI扫描后,测定相同感兴趣区（ROI）的各向异性分数（FA）值和表观扩散系数（ADC）值进行比较。结果：与NC组比较, AD组前额叶、颞叶、海马等部位FA值降低,颞叶、海马等部位ADC值升高（P〈0.05）;aMCI组仅扣带束FA值降低,与AD组比差异有统计学意义（P〈0.05）;SIVD组下额枕束等部位FA值下降,ADC值升高,与AD组比较差异有统计学意义（P〈0.05）。结论：DTI可以用来评估白质纤维束完整性,AD组白质损害甚于aMCI患者;扣带束FA值可以作为aMCI患者筛查的指标;根据受累部位不同可对SIVD与AD进行鉴别。     

皮质下缺血性血管性痴呆患者脑白质损害的磁共振弥散张量成像研究

目的:应用磁共振弥散张量成像技术(DTI)观察皮质下缺血性血管性痴呆(SIVD)患者脑白质损害程度,探讨DTI对SIVD白质损害的评估及与阿尔茨海默病(AD)鉴别诊断价值。方法:研究对象分为3组,分别是健康老年人(NC)、皮质下缺血性血管性痴呆(SIVD)患者、AD患者,每组各20例。行常规MR I和DTI扫描后,测定相同感兴趣区(RO I)的各向异性分数(FA)值和表观扩散系数(ADC)值进行比较。结果:SIVD组下额枕束、胼胝体膝部、胼胝体压部、上纵束等部位FA值下降,ADC值升高,与NC、AD组比较差异有统计学意义(P<0.05)。与NC组比较,AD组前额叶、颞叶、海马、下额枕束、胼胝体膝部和扣带束等部位FA值降低,颞叶、海马等部位ADC值升高,两组差异具有显著性(P<0.05);结论:DTI可以用来评估痴呆患者白质损害的程度,SIVD患者以下额枕束、胼胝体膝部、胼胝体压部、上纵束等部位受累为主,可作为与AD鉴别的客观指标。     

皮质下梗死后认知功能障碍与白质纤维束完整性的扩散张量成像研究

目的采用扩散张量成像(DTI)分析白质纤维束完整性和损伤程度,并探讨脑卒中后认知功能障碍的发生机制。方法选择2016年3月至2018年12月共37例皮质下梗死患者,采用蒙特利尔认知评价量表(MoCA)评价认知功能,同时通过DTI获取关键兴趣区白质纤维束部分各向异性(FA),Pearson相关分析和偏相关分析探讨白质纤维束FA值与MoCA评分的相关性,并采用多因素线性逐步回归分析验证二者的线性数量关系。结果相关分析显示,皮质下梗死后认知功能障碍患者MoCA评分与患侧内囊前肢、前后放射冠、钩束、上纵束和下额枕束,健侧扣带回及双侧外囊FA值呈正相关(均P 0.05);进一步行多因素线性逐步回归,患侧上纵束(P=0.042)和下额枕束(P=0.006)FA值与MoCA评分存在线性回归关系。结论患侧上纵束和下额枕束完整性损害可以作为皮质下梗死后认知功能障碍的影像学标记。     

2型糖尿病合并认知功能障碍患者的脑白质结构变化的影像学特征分析

目的探讨2型糖尿病(T2DM)合并认知功能障碍(T2DM-CI)患者的脑白质结构变化特征。方法纳入33例T2DM-CI患者(T2DM-CI组)、35例T2DM无合并认知功能障碍患者(T2DM-nonCI组)及43例无DM和认知功能障碍者为对照组。应用MR DTI序列检查,利用图集分割的方法计算脑白质20条纤维束弥散参数,比较组间差异,并与认知功能进行相关性分析。结果 3组受试者脑白质纤维束FA值呈下降趋势,MD值呈上升趋势。T2DM-CI组与T2DMnon CI组比较,双侧皮质脊髓束、右侧扣带束海马、胼胝体体部、胼胝体压部、右侧下额枕束、右侧下纵束的FA值差异有显著性(均P 0. 05/20条纤维束)。其中,胼胝体压部、右侧下纵束与语言功能显著相关;双侧皮质脊髓束,胼胝体压部与处理速度差异有显著性(均P 0. 05)。双侧皮质脊髓束、胼胝体压部、双侧下额枕束,双侧上纵束的MD值差异有显著性(均P 0. 05/20条纤维束)。其中,右侧下额枕束、右侧上纵束与语言功能差异有显著性(均P 0. 05)。结论T2DM-CI患者脑白质结构完整性受到破坏,其中胼胝体压部、下纵束、下额枕束、上纵束损伤可能与T2DM-CI患者语言功能受损相关,皮质脊髓束、胼胝体压部损伤可能与处理速度受损相关。     

语义性痴呆结构性磁共振成像研究

目的分析语义性痴呆患者灰质和白质结构变化,提高对其病理改变和发生机制的认识。方法采用3.0T MRI扫描仪对16例语义性痴呆患者和17例正常对照者进行全脑扫描,扫描序列包括三维高分辨力结构像和扩散张量成像(DTI)。通过专业统计软件分别对全脑灰质密度和白质纤维束部分各向异性(FA)值进行分析,比较两组受试者全脑灰质密度(P0.001,Voxel338)和白质纤维束FA值(P0.005,Voxel103)。结果与对照组相比,语义性痴呆组患者双侧颞叶,特别是颞极表现为灰质密度显著降低,以左侧大脑半球额颞顶叶灰质密度减低区域更为广泛,包括左侧颞下回、缘上回、顶下回和额中回;同时双侧颞叶白质纤维束FA值显著降低,包括双侧钩束、左侧扣带(海马)纤维和双侧下额枕束。白质纤维束FA值分析结果与VBM法所显示的灰质密度在解剖学上呈现极高的一致性。结论本研究在体揭示了语义性痴呆的病理学和解剖学基础,为理解语义性痴呆的病理学机制提供了客观佐证。     

路易体痴呆和帕金森病白质纤维束改变的比较

目的研究路易体痴呆(DLB)和帕金森病(PD)患者的脑白质纤维束的改变情况。方法对10例DLB患者(DLB组)、16例PD患者(PD组)及16例正常对照者(正常对照组)进行DTI扫描,采用基于纤维骨架的空间统计方法(TBSS)对三组全脑DTI的各向异性分数(FA)和平均弥散率(MD)两两比较,并分析FA值、MD值与临床数据的相关性。结果与正常对照组比较,DLB组左下纵束、左下额枕束、双侧上纵束FA值、MD值明显改变(P=0.002,P=0.012;P=0.013,P=0.015),而PD组仅胼胝体白质纤维束MD值明显改变(P=0.036)。与PD组比较,DLB组左下纵束、左下额枕束FA值、MD值明显改变(P=0.04;P=0.005)。DLB组左下纵束、左下额枕束FA值与病程呈负相关(r=-0.708,P0.05),与MMSE评分呈正相关(r=0.023,P0.05),左上纵束MD值与统一PD评定量表Ⅲ呈正相关(r=0.682,P0.05)。结论 DLB患者会出现明显的白质纤维束改变,尤其是左下纵束、左下额枕束的改变对DLB的早期诊断有着重要的参考价值。     

首发精神分裂症阳性症状为主型患者脑弥散张量成像研究

目的 探讨首发精神分裂症阳性症状为主型患者主要脑区白质纤维束有无异常.方法 对未系统使用过精神药物治疗的20例首发精神分裂症阳性症状为主型患者和20名正常对照进行磁共振弥散张量成像(DTI)扫描,测量胼胝体膝部、压部、双侧额叶白质、双侧扣带束前部和双侧海马头部分各向异性(FA)值.结果 ①患者组及对照组组内比较,左右侧FA值差异均无统计学意义(P>0.05).②患者组左侧海马头和胼胝体压部FA值[(0.17±0.03),(0.73±0.09)]显著低于对照组[(0.20±0.02),(0.79±0.05)],差异均有统计学意义(P<0.05);③患者组左右侧扣带束前部FA值[(0.28±0.06),(0.29±0.05)]低于对照组[(0.43±0.07),(0.38±0.08)],差异均有统计学意义(P<0.01).结论 首发精神分裂症阳性症状为主型患者双侧扣带束前部、胼胝体压部及左侧海马头的白质纤维束完整性受损,提示其可能存在脑神经发育连接异常.     

帕金森病合并认知功能障碍与脑白质纤维束改变的关系

目的探讨帕金森病(PD)合并认知功能障碍与认知相关脑白质纤维束改变的关系。方法纳入PD患者35例,根据蒙特利尔认知评估量表(MoCA)评分将PD患者分为PD认知功能正常组(PD-nCI,n=14)和PD认知功能障碍组(PD-CI,n=21);另选择同期行查体的健康志愿者20名作为对照组。所有受试者行弥散张量成像(DTI)检查,通过基于纤维束的空间统计分析(tract-based spatial statistics,TBSS)方法选出与认知相关的脑白质纤维束,并测量各纤维束部分各向异性(fractional anisotropy,FA)值。比较各组不同纤维束FA值差异,采用Pearson相关分析法分析PD-CI组差异有统计学意义的纤维束FA值与MoCA评分的相关性。结果(1)3组间胼胝体膝部、胼胝体体部、胼胝体压部、右扣带回(海马)、左扣带回(海马)、右穹窿/终纹、左穹窿/终纹、右上额枕束、左上额枕束FA值比较存在统计学差异(均P0.05),PD-nCI组和PD-CI组间胼胝体膝部、胼胝体体部、胼胝体压部、右扣带回(海马)、左扣带回(海马)、左穹窿/终纹、右上额枕束、左上额枕束FA值比较存在统计学差异(均P0.05);(2)PD-CI组胼胝体压部、右扣带回(海马)、右上额枕束、左上额枕束FA值与MoCA评分呈正相关(均P0.05)。结论 PD患者认知功能损害程度与胼胝体压部、右扣带回(海马)、右上额枕束和左上额枕束等纤维束病变严重程度呈正相关。     

Disorganization of anatomical connectivity in obsessive compulsive disorder: A multi-parameter diffusion tensor imaging study in a subpopulation of patients

Obsessive–compulsive disorder (OCD) is thought to involve large-scale brain systems but the anatomical connectivity via association fibers has not been specifically investigated yet.We evaluated organization and directionality of the major fiber bundles in a subpopulation of OCD, including washers and checkers who presented decision making deficits, by measuring MRI parameters related to water self-diffusion (Fractional Anisotropy, FA) and fiber directionality (Principal Diffusion Direction, PDD) in 15 OCD and 16 control subjects.OCD patients showed significantly lower FA and altered PDD along the corpus callosum, cingulum, superior longitudinal fasciculus, and inferior fronto-occipital fasciculus bilaterally. The track-based analysis of the inferior fronto-occipital fasciculus confirmed a significant bilateral FA reduction. Lower FA values in the inferior fronto-occipital fasciculus, superior longitudinal fasciculus and corpus callosum correlated with symptom severity and neuropsychological performance.This multi-parameter MRI study revealed specific white matter abnormalities in OCD suggesting tract disorganization as main feature, reflected by local changes in fiber directionality. This altered anatomical connectivity might play a specific role in OCD pathophysiology.     

弥漫性轴索损伤后早期磁共振弥散张量成像与工作记忆障碍的相关性研究

目的探讨磁共振弥散张量成像(DTI)对弥漫性轴索损伤(DAI)导致工作记忆障碍早期诊断及预后评估的价值。方法分别对10例DAI患者(DAI组)和10例健康志愿者(正常对照组)行DTI检查,并对两组DTI图像的钩束、皮质脊髓束、胼胝体和扣带回感兴趣区的部分各向异性(FA)值进行比较分析。DAI后6个月对患者与健康志愿者行认知量表评估,并行对比分析;另外将DAI组FA值与其认知量表评分行直线相关分析。结果与对照组相比,DAI患者4个感兴趣区的FA值显著降低(P<0.05),恢复期总体认知能力略降低,但无统计学意义(P>0.05),而工作记忆功能却显著降低(P<0.05)。DAI患者中的钩束和皮质脊髓束的FA值与工作记忆功能呈正相关(r分别为0.898和0.797,P<0.05);胼胝体和扣带回FA值与工作记忆功能无明显相关性(r分别为0.432和0.387,P>0.05)。结论 DTI技术可为DAI导致的工作记忆障碍早期诊断和预后评估提供依据。     

弥散张量成像技术预测遗忘型轻度认知障碍患者向老年性痴呆转化的随访研究

目的:探讨弥散张量成像技术(diffusion tensor imaging,DTI)对遗忘型轻度认知功能障碍(aMCI)向老年性痴呆(AD)转化的预测作用。方法:41例aMCI患者(aMCI组)常规予核磁共振(MRI)和DTI扫描,测定感兴趣区的各向异性分数(fractional anisotropy,FA)和表观扩散系数(apparent diffusion coefficient,ADC),以20名老年健康志愿者作为对照(正常对照组)并随访1~3年。结果:与正常对照组比较,aMCI组41例患者中有22例扣带束FA基线值偏低(P0.05),随访1~3年后,其中有19例转化为AD;另外19例扣带束FA值正常的aMCI患者只有2例转化为AD。与非转化AD者比较,AD转化者前额叶、颞叶、海马、下额枕束、胼胝体膝部和扣带束等部位FA值降低(P均0.01),颞叶、海马等部位ADC值升高(P均0.05)。结论:DTI技术具有预测aMCI向AD转化的作用,aMCI患者扣带束FA值低可能是aMCI向AD转化的敏感指标。     

阿尔茨海默病颞干纤维束扩散张量成像研究

目的应用扩散张量成像(DTI)研究阿尔茨海默病和遗忘型轻度认知损害患者白质和颞干纤维束部分各向异性(FA)值变化特点,探讨颞干纤维束损伤机制及其对阿尔茨海默病和遗忘型轻度认知损害的诊断与鉴别诊断价值。方法应用常规MRI和DTI测量阿尔茨海默病(10例)、遗忘型轻度认知损害(10例)和正常对照者(10例)颞干纤维束(包括前连合、钩束、额枕下束)及前额叶、颞叶、顶叶、枕叶白质FA值,比较各组受试者左右侧对称部位白质和颞干纤维束FA值变化。结果各组受试者左右侧对称部位白质和颞干纤维束FA值差异无统计学意义(均P0.05),但其前连合、钩束、额枕下束及前额叶白质FA值差异具有统计学意义(均P0.05)。其中,阿尔茨海默病组前连合、钩束、额枕下束FA值低于遗忘型轻度认知损害组(均P0.05),前连合、钩束、额枕下束及前额叶、顶叶白质FA值低于正常对照组(均P0.05);而遗忘型轻度认知损害组与正常对照组前连合、钩束、额枕下束及前额叶白质FA值差异无统计学意义(均P0.05)。结论阿尔茨海默病和遗忘型轻度认知损害患者与正常老年人颞干纤维束FA值存在显著差异,提示颞干纤维束在阿尔茨海默病患者白质损伤中具有重要意义,DTI检查有助于阿尔茨海默病与遗忘型轻度认知损害和正常老龄化的鉴别诊断。阿尔茨海默病前连合、钩束、额枕下束及前额叶、顶叶白质FA值异常具有良好的临床诊断价值。     

Freezing of gait in Parkinson’s disease: gray and white matter abnormalities

Freezing of gait (FOG) is a disabling disorder that often affects Parkinson’s disease (PD) patients in advanced stages of the disease. To study structural gray matter (GM) and white matter (WM) changes in PD patients with and without FOG, twenty-one PD patients with FOG (PD-FOG), 16 PD patients without FOG (PD-nFOG) and 19 healthy subjects (HS) underwent a standardized MRI protocol. For the gray matter evaluation, cortical volume (CV), cortical thickness (CTh), and surface area (SA) were analyzed using the FreeSurfer pipeline. For the white matter evaluation, DTI images were analyzed using tracts constrained by underlying anatomy (TRACULA) toolbox in FreeSurfer. PD-FOG patients exhibited lower CTh than HS in the mesial surface of both cerebral hemispheres, including the superior frontal gyrus, paracentral lobule, posterior cingulate cortex, precuneus and pericalcarine cortex, and in the right dorsolateral prefrontal cortex. Moreover, significant WM changes were observed in PD-FOG patients in comparison with HS in the superior longitudinal fasciculus, uncinate fasciculus, cingulum cingulate gyrus and inferior longitudinal fasciculus (prevalently in the right hemisphere) and in the frontal radiations of the corpus callosum. DTI abnormalities in specific WM bundles correlated significantly with cognitive measures. The damage of multiple cortical areas involved in high-level gait control together with WM disruption between motor, cognitive and limbic structures may represent the anatomical correlate of FOG.     

White matter integrity predicts delay discounting behavior in 9- to 23-year-olds: a diffusion tensor imaging study

Healthy participants (n = 79), ages 9-23, completed a delay discounting task assessing the extent to which the value of a monetary reward declines as the delay to its receipt increases. Diffusion tensor imaging (DTI) was used to evaluate how individual differences in delay discounting relate to variation in fractional anisotropy (FA) and mean diffusivity (MD) within whole-brain white matter using voxel-based regressions. Given that rapid prefrontal lobe development is occurring during this age range and that functional imaging studies have implicated the prefrontal cortex in discounting behavior, we hypothesized that differences in FA and MD would be associated with alterations in the discounting rate. The analyses revealed a number of clusters where less impulsive performance on the delay discounting task was associated with higher FA and lower MD. The clusters were located primarily in bilateral frontal and temporal lobes and were localized within white matter tracts, including portions of the inferior and superior longitudinal fasciculi, anterior thalamic radiation, uncinate fasciculus, inferior fronto-occipital fasciculus, corticospinal tract, and splenium of the corpus callosum. FA increased and MD decreased with age in the majority of these regions. Some, but not all, of the discounting/DTI associations remained significant after controlling for age. Findings are discussed in terms of both developmental and age-independent effects of white matter organization on discounting behavior.     

Tract-specific analysis of white matter integrity disruption in schizophrenia

Several studies have suggested that white matter integrity is disrupted in some brain regions in patients with schizophrenia. The purpose of this study was to assess the white matter integrity of the cingulum, uncinate fasciculus, fornix, and corpus callosum using diffusion tensor imaging (DTI). Participants comprised 39 patients with schizophrenia (19 males and 20 females) and 40 age-matched normal controls (20 males and 20 females). We quantitatively assessed the fractional anisotropy (FA) and apparent diffusion coefficient (ADC) of the anterior cingulum, body of the cingulum, uncinate fasciculus, fornix, and corpus callosum on a tract-specific basis using diffusion tensor tractography (DTT). Group differences in FA and ADC between the patients and normal controls were sought. Additional exploratory analyses of the relationship between the FA or ADC and four clinical parameters (i.e., illness duration, positive symptom scores, negative symptom scores, and medication dosage) were performed. Results were analyzed in gender-combined and gender-separated group comparisons. FA was significantly lower on both sides of the anterior cingulum, uncinate fasciculus, and fornix in the schizophrenia patients irrespective of gender group separation. In the gender-combined analyses, significantly higher ADC values were demonstrated in the schizophrenia patients in both sides of the anterior cingulum, body of the cingulum and uncinate fasciculus, the left fornix, and the corpus callosum, compared with those of the normal controls. In the gender-separated analyses, the male patients showed higher ADC in the left anterior cingulum, the bilateral cingulum bodies, and the bilateral uncinate fasciculi. The female patients showed higher ADC in the right anterior cingulum, the left fornix, and the bilateral uncinate fasciculus. In correlation analyses, a significant negative correlation was found between illness duration and ADC in the right anterior cingulum in the gender-combined analyses. The gender-separated analyses found that the male patients had a significant negative correlation between negative symptom scores and FA in the right fornix, a positive correlation between illness duration and FA in the right anterior cingulum, and a negative correlation between illness duration and FA in the left uncinate fasciculus. Our DTI study showed that the integrity of white matter is disrupted in patients with schizophrenia. The results of our sub-analyses suggest that changes in FA and ADC may be related to negative symptom scores or illness duration.     

Diffusion tensor anisotropy in adolescents and adults

We acquired diffusion tensor images on 33 normal adults aged 22-64 and 15 adolescents aged 14-21. We assessed relative anisotropy in stereotaxically located regions of interest in the internal capsule, corpus callosum, anterior thalamic radiations, frontal anterior fasciculus, fronto-occipital fasciculus, temporal lobe white matter, cingulum bundle, frontal inferior longitudinal fasciculus, frontal superior longitudinal fasciculus, and optic radiations. All of these structures except the optic radiations, corpus callosum, and frontal inferior longitudinal fasciculus exhibited differences in anisotropy between adolescents and adults. Areas with anisotropy increasing with age included the anterior limb of the internal capsule, superior levels of the frontal superior longitudinal fasciculus and the inferior portion of the temporal white matter. Areas with anisotropy decreasing with age included the posterior limb of the internal capsule, anterior thalamic radiations, fronto-occipital fasciculus, anterior portion of the frontal anterior fasciculus, inferior portion of the frontal superior longitudinal fasciculus, cingulum bundle and superior portion of the temporal axis. Sex differences were found in the majority of areas but were most marked in the cingulum bundle and internal capsule. These results suggest continuing white matter development between adolescence and adulthood.     

Mean diffusivity and fractional anisotropy as indicators of disease and genetic liability to schizophrenia

The goals of this study were to first determine whether the fractional anisotropy (FA) and mean diffusivity (MD) of major white matter pathways associate with schizophrenia, and secondly to characterize the extent to which differences in these metrics might reflect a genetic predisposition to schizophrenia. Differences in FA and MD were identified using a comprehensive atlas-based tract mapping approach using diffusion tensor imaging and high-resolution structural data from 35 patients, 28 unaffected first-degree relatives of patients, 29 community controls, and 14 first-degree relatives of controls. Schizophrenia patients had significantly higher MD in the following tracts compared to controls: the right anterior thalamic radiations, the forceps minor, the bilateral inferior fronto-occipital fasciculus (IFO), the temporal component of the left superior longitudinal fasciculus (tSLF), and the bilateral uncinate. FA showed schizophrenia effects and a linear relationship to genetic liability (represented by schizophrenia patients, first-degree relatives, and controls) for the bilateral IFO, the left inferior longitudinal fasciculus (ILF), and the left tSLF. Diffusion tensor imaging studies have previously identified white matter abnormalities in all three of these tracts in schizophrenia; however, this study is the first to identify a significant genetic liability. Thus, FA of these three tracts may serve as biomarkers for studies seeking to identify how genes influence brain structure predisposing to schizophrenia. However, differences in FA and MD in frontal and temporal white matter pathways may be additionally driven by state variables that involve processes associated with the disease.