Changes in Parietal Lobe as A Typical Imaging Finding in Patients with Alzheimer's Disease

  Objective  To observe the metabolic and structural changes in different cerebral areas in patients with Alzheimer's disease (AD) and to explore the value of the changes in parietal lobe in the diagnosis of AD.

  Methods  Totally 123 patients with suspected AD who were assessed in our hospital from January 2007 to December 2010 were entrolled in this study. The brain functions were evaluaed using fluorodeoxy glucose-positron emission tomography (FDG-PET). Changes in different cerebral areas were evaluated by direct observation, SUV measurement, and NeuroQ analysis. The brain structure was obseved under three-dimensional megnatic resonance imaging (MRI), which were further anlysed via voxel-based morphometric (VBM) and diffusion tensor imaging (DTI).

  Results  Totally 41 patients were diagnosed as probable AD and 43 as possible AD. FDG-PET revealed that, among these 84 patients, hypomatebolism was detected in the parietal lobe of all patients (100%), and also in posterior cingutate (79.8%), posterior temporoparietal lobe (71.4%), and medial temple lobe (61.9%). MRI showed atrophy on parietal lobe in 67.9% (57 cases of both sides) to 84.5% (71 cases of single side) of the patients. Among 24 patients who can be assessed using VBM, MRI showed the atrophy of parietal lobe was much more obvious. No hypomatebolism or atrophy of the parietal lobe was found in 12 clinically probable frontotemporal dementia patients.

  Conclusion  Hypometabolism (as shown by functional imaging) and atrophy (as shown by structural imaging) of the parietal lobe can be suggestive for the diagnosis of AD.