Morphological changes of cerebral cortex in primary open-angle glaucoma patients under magnetic resonance imaging

Abstract

To observe the morphology changes of cerebral cortex in primary open-angle glaucoma (POAG) patients, and to explore the damage mechanism in the central nerve system. 30 patients, 19 males and 11 females (age ranged from 26 to 82 years old), who were diagnosed with POAG in the department of ophthalmology at Huashan Hospital of Fudan University from February 2011 to December 2012 were enrolled. Meanwhile, additional 30 age- and sex- matched patients were collected as controls. All subjects underwent a complete ophthalmic evaluation. As for magnetic resonance imaging (MRI), we adopted the scans of T1WI, T2WI and fluid attenuated inversion recovery (FLAIR) on a Siemens Magneton Verio 3T MRI machine with a 12-channel head coil. Subjects with space occupying or vascular lesion in brain imaging were excluded from the study. The three-dimensional magnetization prepared rapid acquisition gradient echo sequence (3D-MPRAGE) was used to acquire the volume data of whole brain of all subjects. SPM8 and VBM8 toolbox were used to analyze the image data. Voxel-based analysis was done for whole brain grey matter images. Compared with the control group, the volume of grey matter from several brain regions of the POAG patients decreased. These structures included left lingual gyrus (t=3.207, P=0.002), left medial frontal gyrus (t=2.912, P=0.004), right superior frontal gyrus (t=2.745, P=0.005), left middle temporal gyrus (t=2.958, P=0.003), right precuneus (t=3.291, P=0.001), right postcentral gyrus (t=3.306, P=0.001), left inferior parietal lobule(t=2.716, P=0.006), left parahippocampa gyrus (t=2.815, P=0.005). The results were assessed with comparative t-test to perform statistical analysis. When t>2.479, P<0.01, the difference between the two groups was considered statistically significant. The volume of grey matter in POAG patients' brain decreased in several regions. It is illustrated that POAG is a syndrome, which causes damages in the brain of POAG patients at multi-aspects and multi-levels. The damages contained not only injuries in the visual pathway, but also morphological and functional changes in many other brain regions.