Guedj Eric, Barbeau Emmanuel J, Didic Mira, Felician Olivier, de Laforte Catherine, Ranjeva Jean-Philippe, Poncet Michel, Cozzone Patrick J, Mundler Olivier, Ceccaldi Mathieu
Service Central de Biophysique et de Médecine Nucléaire, Centre Hospitalo-Universitaire de la Timone, 264 rue Saint-Pierre, 13385, Marseille Cedex 5, France.
Eur J Nucl Med Mol Imaging. 2009 Jul;36(7):1101-12. doi: 10.1007/s00259-009-1060-x. Epub 2009 Feb 18.
Cortical atrophy is correlated with the progression of neuropathological lesions within the medial temporal lobes (MTL) in Alzheimer's disease (AD). Our aim was to determine which local and remote functional changes result from MTL volume loss at the predementia stage.
We studied the relationship between entorhinal and hippocampal MR volumes and whole-brain SPECT perfusion via a voxel-based correlative analysis in 19 patients with amnestic mild cognitive impairment with a memory profile suggestive of early AD.
Right MTL volumes were positively correlated with remote posterior perfusion of the posterior cingulate cortex, and negatively correlated with remote anterior perfusion of the right medial and dorsolateral prefrontal cortex. There was no local correlation between volumes and perfusion within the MTL.
These findings provide further insight into functional changes that result from MTL volume loss during the predementia stage of AD. The positive correlation between MTL volumes and posterior cingulate perfusion may reflect the deafferentation of a temporocingulate network due to mediotemporal degeneration. The paradoxical negative correlation between MTL volumes and prefrontal perfusion may result from recruitment of an alternative anterior temporofrontal network. It remains to be investigated how the "net sum" of this perfusion modulation affects memory and other cognitive domains through a possible compensatory perspective.
皮质萎缩与阿尔茨海默病（AD）内侧颞叶（MTL）神经病理病变的进展相关。我们的目的是确定在痴呆前期MTL体积减少会导致哪些局部和远程功能变化。
我们通过基于体素的相关性分析，研究了19例遗忘型轻度认知障碍患者的内嗅和海马磁共振体积与全脑单光子发射计算机断层扫描（SPECT）灌注之间的关系，这些患者的记忆特征提示早期AD。
右侧MTL体积与后扣带回皮质的远程后部灌注呈正相关，与右侧内侧和背外侧前额叶皮质的远程前部灌注呈负相关。MTL内体积与灌注之间无局部相关性。
这些发现进一步深入了解了AD痴呆前期MTL体积减少所导致的功能变化。MTL体积与后扣带回灌注之间的正相关可能反映了由于颞中回变性导致的颞扣带回网络传入缺失。MTL体积与前额叶灌注之间矛盾的负相关可能是由于替代性前颞叶-额叶网络的募集。通过可能的代偿角度，这种灌注调节的“净总和”如何影响记忆和其他认知领域仍有待研究。
