Filippi Christopher G, Lin Doris D M, Tsiouris Apostolos J, Watts Richard, Packard A Maurine, Heier Linda A, Uluğ Aziz M
Department of Radiology, New York Presbyterian Hospital-Weill Medical College of Cornell University, NY, USA.
Radiology. 2003 Oct;229(1):44-50. doi: 10.1148/radiol.2291020049. Epub 2003 Aug 14.
To determine whether diffusion-tensor magnetic resonance (MR) imaging can depict abnormalities in patients with a diagnosis of developmental delay but structurally normal brain MR imaging results.
Twenty pediatric patients who received a diagnosis of developmental delay underwent brain MR examinations, including diffusion-tensor MR imaging. The MR findings in these patients were compared with those in 10 age-matched neurodevelopmentally healthy children. Diffusion constant (Dav) and anisotropy were measured bilaterally in regions of interest in the centrum semiovale, corona radiata, internal capsule, corpus callosum, and subcortical white matter of the frontal and parieto-occipital lobes. By using a one-tailed Student t test in the positive direction for Dav and in the negative direction for anisotropy and P <.05 to indicate a significant difference, the Dav and anisotropy values for children with developmental delay were compared with those for children who were neurodevelopmentally healthy.
The children with developmental delay had significant increases in Dav in all measured structures (P, <.001 to <.03). Significant decreases in anisotropy were detected in all white matter fiber tracts studied (P, <.001 to <.03) except the posterior limb of the internal capsule.
In the children with developmental delay, diffusion-tensor MR imaging depicted decreases in anisotropy and increases in Dav in the white matter fiber tracts, which appeared to be normal at conventional MR imaging.
确定扩散张量磁共振成像（MRI）能否描绘出诊断为发育迟缓但脑MRI结构正常的患者的异常情况。
20例诊断为发育迟缓的儿科患者接受了脑部MRI检查，包括扩散张量MRI。将这些患者的MRI表现与10名年龄匹配的神经发育正常儿童的表现进行比较。在半卵圆中心、放射冠、内囊、胼胝体以及额叶和顶枕叶皮质下白质的感兴趣区域双侧测量扩散常数（Dav）和各向异性。通过对Dav使用正向单尾Student t检验，对各向异性使用负向单尾Student t检验，且P <.05表示有显著差异，将发育迟缓儿童的Dav和各向异性值与神经发育正常儿童的进行比较。
发育迟缓儿童所有测量结构的Dav均显著增加（P <.001至<.03）。除内囊后肢外，所有研究的白质纤维束的各向异性均显著降低（P <.001至<.03）。
在发育迟缓儿童中，扩散张量MRI显示白质纤维束的各向异性降低和Dav增加，而这些在传统MRI上看似正常。
