No abstract

Presentation schedule is subject to change. For the most up-to-date information, visit www.entannualmeeting.org. Methods:The subjects underwent a polysomnography study to determine the severity of OSA and DTI scans to detect fiber integrity. Fractional anisotropy (FA), a measure of fiber integrity, was derived from the diffusion tensor, resulting in a whole brain FA map. The FA maps were compared using voxel-based statistics to determine differences between severe OSA and control groups, with age and sex as a covariate. The correlation between FA value and clinical severity was performed.Results: Twenty patients with severe OSA (apnea/hypopnea index, AHI >30/h) and 14 sex-and age-matched healthy volunteers (AHI <5/h) were recruited. The exploratory groupwise comparison showed that severe OSA patients exhibited reduced FA values in several brain clusters, including the white matter underlying amygdala, superior temporal gyrus, inferior parietal lobule, precuneus, postcentral gyrus, anterior cingulate gyrus, claustrum, insula, basal ganglia, tapetum, and cerebral peduncle compared with controls. The FA values were negatively correlated with clinical disease severity.Conclusions: This study indicates that OSA patients have impaired white matter integrity in vulnerable regions, associated with increased disease severity. The findings likely represent the pathological process of the brain in OSA patients.

Objectives: 1) Evaluate the accuracy of Watch PAT in diagnosing sleep-disordered breathing (SDB). 2) Compare the results of Watch PAT and polysomnography (PSG). Methods: Prospective study performed between February and December 2012. Thirty patients with suggestive complaints of respiratory sleep disorder underwent Watch PAT and polysomnography simultaneously. Results: Twenty men and ten women underwent the sleep studies. Mean age was 42.8 ± 12.32 years. There was a trend that the apnea / hypopnea index (AHI) of Watch PAT was significantly higher than that of PSG (p<0.001); however the values of AHI of both sleep studies were significantly correlated (r = 0.762). There was also a high correlation between the values of the following variables: minimum oxygen saturation (r = 0.842, p<0.001), oxygen saturation <90% (r = 0.799, p <0.001), and mean heart frequency (r = 0.951, p <0.001). The analysis which used ROC curve to test the diagnostic efficiency of Watch PAT concluded that the area under the curve could reach 0.727 if the threshold of 12 events/hour was used as the cut-off point in this study with a sensitivity of 96.2% and a specificity of 60%. When analyzing the severe cases of obstructive sleep apnea (OSA) (AHI ≥ 30 events/hour), the area under the curve was 0.846 with a sensitivity of 77.8% and a specificity of 86.4%. Conclusions: Watch PAT tends to overestimate the AHI when compared with PSG, especially for mild OSA. The Watch PAT is an alternative method that is reliable and highly sensitive for the diagnosis of SDB.