Cine Magnetic Resonance Imaging During Sleep:Dynamics Of Upper Airway Of Obstructive Sleep Apnea Hypopnea Syndrome Patients

Obstructive sleep apnea hypopnea syndrom e(OSAHS)is a common disordercharacterized by repetitive,partial,or com plete obstructionof the upper airway during sleep resulting insleep obstruction,snori ng,fragmented sleep,episodichypoxemia,and excessive daytime sleepiness.At present,there are two kinds of treatment:continuous positive airway pressu re and su rgical treatment.Of all the surgical treatment,improved uvulopala topharyngoplasty is the most commonly used.However,the success rate of OSAHS patient without screening is only about 50%,so it is im portant to loca te the obstructive sites before operation,for both success rate and prognosis of the surgery.In this study,cinem a MRI during was used to scan the upper airway of OSAHS patients in both sober and sleep state,then the correlation between the data obtained by the scan and the pol ysomnographic index was analyzed.Moreover,the fiber laryngoscope with Müller maneuver was compared with the MRI results to further explore the advantages and disadvantages of these two preoperative examinations.Part1 Cine Magnetic Resonance Imaging during sleep:retropalatal region and hyoid position of obstructive sleep apneahypopnea syndrome patientsObjective Patients with obstructive sleep apnea hypopnea syndrome underwent preoperative upper airway Cinema MRI scan during wakefu lness and natural sleep to locate the airway obstruction site,and to provide th e evidence for the com ing surgery.At the same time,the data of the retrop alatal region,the hyoid p osition and the data o f polysomnography were analyzed to fi nd out the relationship between them,furthermore,to explore the pathogenesis of the disease.Methods T wenty-five patients,who were diagnosed with OSAHS via polysom nography(PSG)were enrolled in this study from February 2015 to October 2015 in the Otorhinolaryngology—Head and Neck Sur gery,the First Affiliated Hospital of Zhengzhou University.The dynamics of uppe r airway w ere obtained with the Cine-MRI during the awake and asleep states to locate th e airway obstruction site.Correlation analyses were used to analyze the hyoid moving distance,the data of the retropalatal region and the PSG da ta.Six patients were not included because their failure to fall asleep during the MRI scan.Results 1.Analysis of correlation between retropalatal region and AHI index Among the 19 patients who we re included in the study,6 patients' obstruction sites were proved to be multiple,while 13 patients' obstruction sites were located at retropalatal region.During sleep state,the minimum value of anteroposterior diameter of the retropalatal region is relevant with the total recorded time that was spent below90% oxygen saturation(CT90%,r=0.474,p<0.05),the minimum value of transverse diameter of the retropalatal region is relevant with CT90%(r=0.510,p<0.05)and lowest arterial oxygen saturation(LSa O2,r=0.546,p<0.01),the rangeability of the anteroposterior diameter is relevant with apnea hypopnea index(AHI,r=0.622,p<0.01),CT90%(r=0.581,p<0.01)and LSa O2(r=-0.496,p<0.05),the rangeability of the transverse diameter is relevant with AHI(r=0.476,p<0.05)?CT90%(r=0.839,p<0.05)and LSa O2(r=-0.777,p<0.01).2.Analysis of correlation between hyoid position and AHI index The vertical distance that hyoid m oved(VD-HM)in the sleep state was higher than that in the awake state.In this study,the lowest position of the hyoid(LP-H)was positively correlated with the pre operative apnea and hyp opnea index(AHI,r= 0.473,p<0.05).The VD-HM was ne gatively correlated with the LSa O2.(r=-0.437,p<0.05).The VD-HM was positiv ely correlated with the CT90%(r=0.665,p<0.01).Conclusion Cine-MRI during sleep state accurately reflect the upper airway obstruction sites of OSAHS patients,and the diameter of retropalatal region as well as the position of the hyoid may affect the severity of the disease.Part2 Comparison of preoperative screening for patients with obstructive sleep apnea hypopnea syndrome by Cinema Magnetic Reasonance Imaging and fiberoptic laryngoscopeObjective Localize the upper airway obstruction of patients with obstructive sleep apnea hypopnea syndrome(OSAHS)by Cinema Magnetic Reasonance Im aging(Cine-MRI) during sleep and fiberoptic laryngoscope with M üller maneuver(FLMM)before operation and discuss the clinical application values.Methods Before operation,FLMM and Cine-MRI were examined in twenty-eight patients who were diagnosed as OSAHS by polysomnography(PSG)and medical examination were enrolled in this study from October 2015 to April 2016 to find out the obstruction of soft palate region,the lingual region and epiglottic.Among those twenty eight patients,six patients were excluded from the study because they could not fall asleep during the examination.Results There are com plete agreement between Cine-MRI and FLMM at locatin g obstruction sites of the soft palate(n=22/n=22),and there are m oderate agreement between Cine-MRI an d FLMM a t locating obstruction sites of the retroglottal region(n=13/n=6),epiglottal region(n=4/n=2)and multiple level(n=13/n=6)Conclusion For those moderate and severe OSAHS pa tients with multiple sites obstruction,preoperative Cine-MRI and FL MM together will be better in locating the blocking sites.Combined with our results,Cine-MRI findings were signi ficantly superior to fiber laryngoscopes in OSAHS patients with multiple sites obstruction.