Mackie Susan, Shaw Philip, Lenroot Rhoshel, Pierson Ron, Greenstein Deanna K, Nugent Tom F, Sharp Wendy S, Giedd Jay N, Rapoport Judith L
Columbia University School of Medicine, New York, NY, USA.
Am J Psychiatry. 2007 Apr;164(4):647-55. doi: 10.1176/ajp.2007.164.4.647.
Anatomic magnetic resonance imaging (MRI) studies have detected smaller cerebellar volumes in children with attention deficit hyperactivity disorder (ADHD) than in comparison subjects. However, the regional specificity and longitudinal progression of these differences remain to be determined. The authors compared the volumes of each lobe of the cerebellar hemispheres and vermis in children with ADHD and comparison subjects and used a new regional cerebellar volume measurement to characterize the developmental trajectory of these differences.
In a longitudinal case-control study, 36 children with ADHD were divided into a group of 18 with better outcomes and a group of 18 with worse outcomes and were compared with 36 matched healthy comparison subjects. The volumes of six cerebellar hemispheric lobes, the central white matter, and three vermal subdivisions were determined from MR images acquired at baseline and two or more follow-up scans conducted at 2-year intervals. A measure of global clinical outcome and DSM-IV criteria were used to define clinical outcome.
In the ADHD groups, a nonprogressive loss of volume was observed in the superior cerebellar vermis; the volume loss persisted regardless of clinical outcome. ADHD subjects with a worse clinical outcome exhibited a downward trajectory in volumes of the right and left inferior-posterior cerebellar lobes, which became progressively smaller during adolescence relative to both comparison subjects and ADHD subjects with a better outcome.
Decreased volume of the superior cerebellar vermis appears to represent an important substrate of the fixed, nonprogressive anatomical changes that underlie ADHD. The cerebellar hemispheres constitute a more plastic, state-specific marker that may prove to be a target for clinical intervention.
解剖磁共振成像（MRI）研究发现，注意缺陷多动障碍（ADHD）儿童的小脑体积比对照对象小。然而，这些差异的区域特异性和纵向进展仍有待确定。作者比较了ADHD儿童和对照对象小脑半球各叶及蚓部的体积，并使用一种新的小脑区域体积测量方法来描述这些差异的发育轨迹。
在一项纵向病例对照研究中，36名ADHD儿童被分为18名预后较好的儿童组和18名预后较差的儿童组，并与36名匹配的健康对照对象进行比较。从基线时获取的磁共振图像以及每隔2年进行的两次或更多次随访扫描中确定六个小脑半球叶、中央白质和三个蚓部亚区的体积。使用总体临床结局指标和《精神疾病诊断与统计手册》第四版（DSM-IV）标准来定义临床结局。
在ADHD组中，观察到小脑上蚓部体积呈非进行性减少；无论临床结局如何，体积减少都持续存在。临床结局较差的ADHD受试者左右下后小脑叶体积呈下降趋势，在青春期相对于对照对象和临床结局较好的ADHD受试者逐渐变小。
小脑上蚓部体积减小似乎是ADHD潜在的固定、非进行性解剖学变化的重要基础。小脑半球构成了一个更具可塑性、与状态相关的标志物，可能被证明是临床干预的靶点。
