Research Division, Institute of Mental Health, Singapore.
Bipolar Disord. 2010 Jun;12(4):383-9. doi: 10.1111/j.1399-5618.2010.00829.x.
Abnormalities of brain white matter have been noted in structural magnetic resonance imaging and diffusion tensor imaging (DTI) studies of bipolar disorder, but there are fewer investigations specifically examining white matter integrity early in the course of illness. In this study, we employed DTI to elucidate white matter changes in adult patients with remitted first-episode mania and hypothesized that first-episode mania was associated with decreased fractional anisotropy in cortical (frontal) and subcortical (thalamus, striatum) white matter as well as white matter tracts (cingulum, corpus callosum).
Diffusion tensor images were acquired from 16 patients with remitted first-episode mania and 16 healthy controls matched for age, gender, handedness, and years of education. Fractional anisotropy and radial and axial diffusivities were analyzed using Tract-Based Spatial Statistics.
Patients had lower fractional anisotropy and higher radial diffusivity in the left anterior frontal white matter, right posterior thalamic radiation, left cingulum, and bilateral sagittal striatum. In addition, increased radial diffusivity was found in the left corpus callosum.
Our findings highlighted that white matter abnormalities were present by the time of remission of first-episode mania. The widespread occurrence of these white matter abnormalities both in first-episode mania and chronic bipolar disorder suggested that disruption of white matter cortical-subcortical networks as well as projection, associative, and commissural tracts is a hallmark of the illness.
在双相情感障碍的结构磁共振成像和弥散张量成像（DTI）研究中已经注意到脑白质异常，但很少有研究专门检查疾病早期的白质完整性。在这项研究中，我们使用 DTI 来阐明缓解期首发躁狂症成年患者的白质变化，并假设首发躁狂症与皮质（额叶）和皮质下（丘脑、纹状体）白质以及白质束（扣带、胼胝体）的分数各向异性降低有关。
从 16 名缓解期首发躁狂症患者和 16 名年龄、性别、利手和受教育年限相匹配的健康对照者中获取弥散张量图像。使用基于束的空间统计学分析分数各向异性、径向和轴向弥散度。
患者左侧额前白质、右侧丘脑后辐射、左侧扣带和双侧矢状纹状体的分数各向异性降低，径向弥散度升高。此外，还发现左侧胼胝体的径向弥散度增加。
我们的发现强调了首发躁狂症缓解时就存在白质异常。这些白质异常在首发躁狂症和慢性双相情感障碍中广泛存在，表明白质皮质-皮质下网络以及投射、联合和连合束的破坏是该疾病的一个标志。
