PURPOSE: We investigated whether there are differences in metabolite ratios of different brain regions between mild and severe obstructive sleep apnea (OSA) patients. MATERIALS AND METHODS: A total of 17 mild OSA and 14 severe OSA patients were enrolled. N-acetyl aspartate (NAA)/creatine (Cr), choline (Cho)/Cr and NAA/Cho ratios were calculated by using multivoxel magnetic resonance spectroscopy (MRS) (TR: 1500, TE: 135 ms) from hippocampus, putamen, insular cortex, thalamus and temporal white matter. The relationship between the two groups was evaluated with Mann-Whitney U test. RESULTS: NAA/Cr ratios obtained from hippocampus was found to be significantly increased in severe OSA patients compared to mild OSA patients (P=.004). Cho/Cr ratios obtained from hippocampus and putamen in severe OSA patients were significantly increased when compared to mild OSA patients (P=.003 and P=.004, respectively). In addition, NAA/Cho ratios of putamen were significantly decreased in severe OSA patients when compared to mild OSA (P=.032). CONCLUSION: MRS identified hypoxia-related metabolite and microstructural changes in hippocampus and putamen. The metabolite changes of increase in NAA/Cr and Cho/Cr ratios and decrease in NAA/Cho ratio were more pronounced with increasing severity of OSA syndrome.
PURPOSE: We investigated whether there are differences in metabolite ratios of different brain regions between mild and severe obstructive sleep apnea (OSA) patients. MATERIALS AND METHODS: A total of 17 mild OSA and 14 severe OSA patients were enrolled. N-acetyl aspartate (NAA)/creatine (Cr), choline (Cho)/Cr and NAA/Cho ratios were calculated by using multivoxel magnetic resonance spectroscopy (MRS) (TR: 1500, TE: 135 ms) from hippocampus, putamen, insular cortex, thalamus and temporal white matter. The relationship between the two groups was evaluated with Mann-Whitney U test. RESULTS:NAA/Cr ratios obtained from hippocampus was found to be significantly increased in severe OSA patients compared to mild OSA patients (P=.004). Cho/Cr ratios obtained from hippocampus and putamen in severe OSA patients were significantly increased when compared to mild OSA patients (P=.003 and P=.004, respectively). In addition, NAA/Cho ratios of putamen were significantly decreased in severe OSA patients when compared to mild OSA (P=.032). CONCLUSION:MRS identified hypoxia-related metabolite and microstructural changes in hippocampus and putamen. The metabolite changes of increase in NAA/Cr and Cho/Cr ratios and decrease in NAA/Cho ratio were more pronounced with increasing severity of OSA syndrome.
Authors: Santosh K Yadav; Rajesh Kumar; Paul M Macey; Mary A Woo; Frisca L Yan-Go; Ronald M Harper Journal: Sleep Date: 2014-05-01 Impact factor: 5.849
Authors: Rajesh Kumar; Salar Farahvar; Jennifer A Ogren; Paul M Macey; Paul M Thompson; Mary A Woo; Frisca L Yan-Go; Ronald M Harper Journal: Neuroimage Clin Date: 2014-01-31 Impact factor: 4.881
Authors: Manoj K Sarma; Paul M Macey; Rajakumar Nagarajan; Ravi Aysola; Ronald M Harper; M Albert Thomas Journal: Sci Rep Date: 2016-09-06 Impact factor: 4.379
Authors: Robert A Darnall; Xi Chen; Krishnamurthy V Nemani; Chrystelle M Sirieix; Barjor Gimi; Susan Knoblach; Betty L McEntire; Carl E Hunt Journal: Pediatr Res Date: 2017-05-03 Impact factor: 3.756