Study On The Pulmonary Vascular And Small Airway Remodeling Of OSAHS Patients In Daytime Sleepiness State

Objective:Using MSCT to evaluate vascular remodeling and airway remodeling in OSAHS patients.To evaluate the clinical value of MSCT in the diagnosis and treatment of patients with OSAHS and observe the effective indexes.Material and methods:17 cases of OSAHS diagnosed by PGS were selected, all of them were male,mean age was 40.6±14.5, average AHI was 39.8±19.4 times per hour.At the same time,10 healthy volunteers were selected as the control group.Among them,4 cases were male and 6 were female, mean age was 39.3±15.3.All objects were given Siemens Definition Flash dual source CT scan of nasopharynx and lung.Patients in the supine position, head advanced, as far as possible to ensure that the head was in the middle line.The nasopharynx scan range from paranasal sinus to hypopharyngeal level, the scan parameters were 120kV and 80mA, scan collimation distance was 1.2 mm, Bf was 31, then using 0.6mm thick layer to reconstruction.After the scan was completed, images were transmitted to the workstation for multi planar reconstruction, and the left to right diameter, anteroposterior diameter and volume of upper airway at soft palate and tongue level were measured, at the same time, length and thickness of the soft palate, adenoid thickness, thickness of the palate were also measured.The lung scan range from the apex to the bottom of lung,scan was performed at the deep end expiratory breath.Scan parameters were 100kV and 50 mA, scan collimation distance was 1.2 mm, Bf was 70, and using 0.6mm thick layer to reconstruction.Imaging datas were deliveried into dual source CT work for 3D reconstruction, the number and diameter (maximum diameter) of theperipheral (subpleural 1cm) small airway and vascular witch was parallel to axial were measured, the measurements were divided into three levels such as the aortic arch level, level of tracheal carina and diaphragm upper 3 cm level. Pumlo software was used to measure the lung volume,mean lung density and pixel index of the whole lung.The results were statistically analyzed using SPSS 16 statistical software. Two groups of samples were compared using t test,correlation analysis and regression analysis were used to analyze the relationship between CT and clinical parameters.Measurement data were expressed as mean plus or minus standard deviation (s).P<0.05 were considered statistically significant.Result K Quantitative evaluation of upper airway between OSAHS patients and healthy volunteers by MSCT:the left to right diameter of soft palate region in OSAHS patients was less than the control group (P< 0.05). The length and thickness of soft palate,thickness of adenoid and tonsil in OSAHS patients were higher than control group (P< 0.05).2、MSCT quantitative study on lung function of OSAHS patients and healthy volunteers:the small peripheral vascular diameter at 3cm above the diaphragm level in OSAHS patients was larger than the control group.The peripheral small tube diameter at tracheal bifurcation level and 3cm above the diaphragm level in OSAHS patients were larger than that of the control group (p<0.05).3、Correlation study between CT measurement of upper airway and PSG parameters:the thickness of the amygdala was in positive correlated with the apnea index.The lingual region volume was in negative correlated with hypopnea index.4、Study on correlation between CT measurement and PFT parameters in OSAHS patients:The number of peripheral blood vessels at the bifurcation of trachea was in negative correlated with FVC.PI (<-900Hu) was in positive correlated with FEV1.PI (-800 ～ 701Hu) was in negative correlated with VT.The two main factors affecting of the lowest blood oxygen saturation were lung volume and the number of peripheral blood vessels at 3cm above the diaphragm.Both of them were in positive correlated with the lowest blood oxygen saturation.5、Correlation study of CT measurement in lung and CT measurement in the upper airway:the number of peripheral small airway at 3cm above the diaphragm was in positive correlated with the length of soft palate and the left to right diameter of the lingual region.The thickness of the amygdala wasin positive correlated with PI (≥700Hu).The thickness of the amygdala was in negative correlated with MLD and PI (-800～-701Hu).Conclusion 1-. The left-right diameter is more meaningful than the anteroposterior diameter in OSAHS patients.MSCT can visually observe the narrow area of the upper airways in awaked OSAHS patients.2、The mean lung density and pixel index in OSAHS patients have indirect reflection with the small airway remodeling.3、Using MSCT to measure the peripheral pulmonary vascular in OSAHS patients can be a reaction of the lowest blood oxygen saturation to some extent.