Kuchtova Barbora, Wurst Zdenek, Mrzilkova Jana, Ibrahim Ibrahim, Tintera Jaroslav, Bartos Ales, Musil Vladimir, Kieslich Karel, Zach Petr
Department of Anatomy, Third Faculty of Medicine, Charles University, Prague, Czech Republic.
National Institute of Mental Health, Topolova 748, 250 67 Klecany, Czech Republic.
Curr Alzheimer Res. 2018;15(6):590-599. doi: 10.2174/1567205015666171227155510.
Alzheimer disease is traditionally conceptualized as a disease of brain gray matter, however, studies with diffusion tensor imaging have demonstrated that Alzheimer disease also involves alterations in white matter integrity. We measured number of tracts, tracts length, tract volume, quantitative anisotropy and general fractional anisotropy of neuronal tracts in subcallosal area, paraterminal gyrus and fornix in patients with Alzheimer disease and healthy age-matched controls. Our hypothesis was that patients with Alzheimer disease should exhibit decrease in the integrity of these white matter structures that are crucial for semantic memory function.
For our study were selected 24 patients with confirmed Alzheimer disease diagnosis and 24 healthy controls (AD center, Department of Neurology, Charles University, Prague, Czech Republic). Statistically significant differences between the patients with Alzheimer disease and the control group were found both on the left and right fornices but only concerning the tract numbers and tract length. The subcallosal area and paraterminal gyrus showed statistically significant differences between the patients with Alzheimer disease and the control group, but only on the left side and only associated with the tract volume and quantitative anisotropy.
Our explanation for these findings lies in the severe hippocampal atrophy (and subsequent loss of function) with compensatory hypertrophy of the subcallosal area and paraterminal gyrus neuronal fibers that occurs in Alzheimer's disease, as an adaptation to the loss of projection from the hippocampal formation via fornix.
传统上，阿尔茨海默病被认为是一种脑灰质疾病，然而，扩散张量成像研究表明，阿尔茨海默病也涉及白质完整性的改变。我们测量了阿尔茨海默病患者和年龄匹配的健康对照者胼胝体下区、终板旁回和穹窿中神经束的数量、神经束长度、神经束体积、定量各向异性和一般分数各向异性。我们的假设是，阿尔茨海默病患者这些对语义记忆功能至关重要的白质结构的完整性应会降低。
我们的研究选取了24例确诊为阿尔茨海默病的患者和24名健康对照者（捷克共和国布拉格查理大学神经病学系阿尔茨海默病中心）。在左右穹窿上，阿尔茨海默病患者与对照组之间均发现有统计学显著差异，但仅涉及神经束数量和神经束长度。胼胝体下区和终板旁回在阿尔茨海默病患者与对照组之间显示出统计学显著差异，但仅在左侧，且仅与神经束体积和定量各向异性有关。
我们对这些发现的解释是，在阿尔茨海默病中，由于海马结构通过穹窿投射丧失，会出现严重的海马萎缩（以及随后的功能丧失），同时胼胝体下区和终板旁回神经元纤维会发生代偿性肥大。
