Clinical Application Of Brain Functional Magnetic Resonance Imaging In Obstructive Sleep Apnea Hypopnea Syndrome

Chapter one Clinical application of 1H-MRS in OSAHS patientsObjective To investigate the variation of multivoxel 1H magnetic resonance spectroscopy(1H-MRS) before and after Continuous Positive Airway Pressure (CPAP) treatment in patients who are suffering from obstructive sleep apnea, hypopnea syndrome (OSAHS).Materials and Methods Fifty cases of moderate or severe OSAHS patients and 25 cases of healthy were performed brain multivoxel 1H-MRS examinations. Twenty-five of the moderate or severe OSAHS patients received CPAP treatment, 25 of them not. Twenty-five of the moderate or severe OSAHS patients were performed brain multivoxel 1H-MRS examinations after CPAP treatment one day and 90 days, other patients were performed brain multivoxel 1H-MRS examinations after CPAP treatment 90 days. The ratios of brain metabolites of frontal lobe was recorded and analyzed respectively. To observe whether the lactate peak appeared or not.Results In region of frontal lobe, The NAA/Cr, NAA/Cho of the patients after treatment 1day(2.3140±0.3128 and 2.0164±0.4240, respectively) and 90 days (2.2812±0.2904 and 2.0180±0.4796) were increased compared with the patients before treatment (2.0212±0.2312 and 1.6088±0.2571), and the difierences were statistically significant (P<0.05). However, they still decreased compared with the healthy (2.7268±0.6071 and 2.4456±0.4375). The NAA/Cr,NAA/Cho of the patients have no significant difference after treatment 1day and 90 days. The NAA/Cr, NAA/Cho of the patients who refused treatment (1.8904±0.2370 and 1.4596±0.2342) significantly lower compared with the first time they were diagnosed(2.0280±0.2093 and 1.6100±0.2746)(P<0.05). Lac peak was not detected in all.Conclusion multivoxel 1H-MRS could demonstrate sensitively the changes of brain metabolism in patients with OSAHS before and after CPAP treatment, and may help clinical therapeutic effect and prognostic evaluation provide objective imaging evidence.Chapter two Clinical application of DTI in OSAHS patientsObjective To investigate the change in patients with obstructive sleep apnea hypopnea syndrome (OSAHS) after continuous positive airway pressure (CPAP) treatment using diffusion tensor imaging (DTI).Materials and Methods Fifty cases of moderate or severe OSAHS patients and 25 cases of healthy were performed brain DTI examinations. Twenty-five of the moderate or severe OSAHS patients received CPAP treatment, and 25 patients of them did not received the treatment. The brain DTI examinations were performed, 25 of the moderate or severe OSAHS patients after CPAP treatment 90 days and 180 days, separately, other patients after refused CPAP treatment 90 days. The apparent diffusion coefficient (ADC) and fractional anisotropy(FA) of frontal lobe was recorded and analyzed respectively.Results The FA of the patients after treatment 90_days (0.3213±0.0294 and 0.3332±0.0303) and 180 days (0.3245±0.0325 and 0.3251±0.0235) were increased compared with the patients before treatment (0.2640±0.0377 and 0.2585±0.0334), The ADC of the patients after treatment 90days (6.4826±0.2909 and 6.4745±0.2763) and 180 days (6.5165±00.3318 and 6.4440±0.3138)were decreased compared with the patients before treatment (6.7959±0.2657 and 6.6814±0.2908), the difierences were statistically significant (P<0.05). However, the FA of healthy (0.32588±10.0351 and 0.3341±0.0339) is still higher significantly than the FA after 90 days and 180 days treatment. The ADC of healthy (6.3903±0.2683 and 6.4287±0.2463) is still decreased significantly. The ADC and FA of the patients have no significant difference after treatment 90 days and 180 days. Ninety follow-up days ADC (6.9565±0.1547 and 6.9052±0.3021) is significantly increased compared with the first diagnosed (6.6077±0.2926 and 6.5175±0.3027)(P<0.001), the ninety follow-up days FA(0.2429±0.0351 and 0.2353±0.0287)is significantly decreased compared with the first diagnosed (0.2819±0.0425 and 0.2864±0.0314)( P<0.001).Conclusion Subtle changes of write matter in OSAHS patients are appreciable by DTI over the course of treatment with CPAP. The fingings provide objective clinical curative effect and prognosis evaluation imaging basis.Chapter three Clinical application of BOLD-fMRI in OSAHS patientsObjective This study was to explore the functional and morphological abnormalities of the resting-state brain of obstructive sleep apnea hypopnea syndrome, by resting-state functional magnetic resonance imaging (fMRI). To investigate the change of brain functional abnormalities of obstructive sleep apnea hypopnea syndrome,before and after treatmentMethods ALL candiatas underwent polysomnography all night by using E-series polysomnography produced in Australia Kangdi. Then, choose 25 healthy and 25 patients.Twenty-five healthy and 25 patients who before and after CPAP received MRI resting state BOLD-fMRI. Regional homogeneity (ReHo), amplitude of frequency fluctuation(ALFF),fractional amplitude of frequency fluctuation (fALFF) approach was used to preprocess the BOLD-fMRI datasets. To explore the functional and anatomical brain abnormalities in obstructive sleep apnea hypopnea syndrome, the t-test was performed. Resulted statistical map was set at the threshold of P<0.05 and the minimum cluster size of 10 voxels (ReHo).Results1.1 Compared with healthy controlsObstructive sleep apnea hypopnea syndrome patients before treatment with decreased ReHo in the right fusiform gyrus, right superior temporal gyrus, double cerebelum,right angular gyrus,left posterior cingulate, left frontal gyrus, right frontal compared with healthy controls. Reduced ALFF in right cerebellum, right insula, left inferior frontal gyrus, right precentral gyrus, left cingulate gyrus etal. Reduced fALFF in right inferior frontal gyrus, left amygdala, right hippocampus, right angular gyrus, left middle occipital gyrus, left precentral gyrus, left superior temporal gyrus, right postcentral gyrus, right superior frontal gyrus.1.2 Compared with healthy controlsObstructive sleep apnea hypopnea syndrome petients after treatment with reduced ReHo in the right cerebellar hemisphere, right spindle gyrus, left middle occipital gyrus, right middle frontal gyrus compared with healthy controls. Decreased ALFF in the Right cuneus, left inferior frontal gyrus, left cingulate gyrus. Decreased fALFF in right inferior frontal gyrus, right middle occipital gyrus, left superior frontal gyrus and left frontal gyrus.1.3 Compared with pre-treatment obstructive sleep apnea hypopnea syndromeObstructive sleep apnea hypopnea syndrome petients after treatment with increased ReHo in the right inferior temporal gyrus, left cingulate gyrus, left postcentral gyrus, right middle frontal gyrus, left superior frontal gyrus, right occipital gyrus compared with pre-treatment. Increased ALFF in theright cerebellar hemisphere, right postcentral gyrus, right precentral gyrus, left superior temporal gyrus, right middle frontal gyrus, right lingual gyrus. Increased fALFF in left middle occipital gyrus, left middle temporal gyrus, right middle frontal gyrus, right posterior central gyrus, right anterior central gyrus.Conclusion1 There is abnormal in resting state brain function of obstructive sleep apnea hypopnea syndrome patients.2 After effective treatment, part of abnormal brain function in obstructive sleep apnea hypopnea syndrome patients can be reversed.