Looi J C L, Svensson L, Lindberg O, Zandbelt B B, Ostberg P, Orndahl E, Wahlund L-O
Academic Unit of Psychological Medicine, Research Centre for the Neurosciences of Ageing, Australian National University Medical School, Canberra Hospital, Canberra, Australia.
AJNR Am J Neuroradiol. 2009 Sep;30(8):1552-60. doi: 10.3174/ajnr.A1640. Epub 2009 Jun 4.
Frontostriatal (including the putamen) circuit-mediated cognitive dysfunction has been implicated in frontotemporal lobar degeneration (FTLD), but not in Alzheimer disease (AD) or healthy aging. We sought to assess putaminal volume as a measure of the structural basis of relative frontostriatal dysfunction in these groups.
We measured putaminal volume in FTLD subtypes: frontotemporal dementia (FTD, n = 12), semantic dementia (SD, n = 13), and progressive nonfluent aphasia (PNFA, n = 9) in comparison with healthy controls (n = 25) and patients with AD (n = 18). Diagnoses were based on accepted clinical criteria. We conducted manual volume measurement of the putamen blinded to the diagnosis on T1 brain MR imaging by using a standardized protocol.
Paired t tests (P < .05) showed that the left putaminal volume was significantly larger than the right in all groups combined. Multivariate analysis of covariance with a Bonferroni correction was used to assess statistical significance among the subject groups (AD, FTD, SD, PNFA, and controls) as independent variables and right/left putaminal volumes as dependent variables (covariates, age and intracranial volume; P < .05). The right putamen in FTD was significantly smaller than in AD and controls; whereas in SD, it was smaller compared with controls with a trend toward being smaller than in AD. There was also a trend toward the putamen in the PNFA being smaller than that in controls and in patients with AD. Across the groups, there was a positive partial correlation between putaminal volume and Mini-Mental State Examination (MMSE).
Right putaminal volume was significantly smaller in FTD, the FTLD subtype with the greatest expected frontostriatal dysfunction; whereas in SD and PNFA, it showed a trend towards being smaller, consistent with expectation, compared to controls and AD; and in SD, compared with AD and controls. Putaminal volume weakly correlated with MMSE.
额颞叶变性（FTLD）与额纹状体（包括壳核）回路介导的认知功能障碍有关，但阿尔茨海默病（AD）或健康衰老与之无关。我们试图评估壳核体积，以此作为这些组中相对额纹状体功能障碍结构基础的一项指标。
我们测量了FTLD各亚型（额颞叶痴呆（FTD，n = 12）、语义性痴呆（SD，n = 13）和进行性非流畅性失语（PNFA，n = 9））的壳核体积，并与健康对照者（n = 25）和AD患者（n = 18）进行比较。诊断基于公认的临床标准。我们采用标准化方案，在对T1加权脑磁共振成像上的诊断不知情的情况下，对壳核进行手动体积测量。
配对t检验（P < 0.05）表明，所有组的左侧壳核体积均显著大于右侧。采用Bonferroni校正的多变量协方差分析用于评估作为自变量的各受试者组（AD、FTD、SD、PNFA和对照）之间以及作为因变量（协变量为年龄和颅内体积；P < 0.05）的右侧/左侧壳核体积之间的统计学显著性。FTD组的右侧壳核显著小于AD组和对照组；而在SD组中，其小于对照组，且有小于AD组的趋势。PNFA组的壳核也有小于对照组和AD患者的趋势。在所有组中，壳核体积与简易精神状态检查表（MMSE）呈正偏相关。
FTD是预期额纹状体功能障碍最严重的FTLD亚型，其右侧壳核体积显著较小；而在SD和PNFA组中，与对照组和AD相比，右侧壳核体积有变小的趋势，符合预期；在SD组中，与AD和对照组相比也是如此。壳核体积与MMSE呈弱相关。
