前伸下颌动作与口腔矫治器对上气道形态影响的一致性分析

Comparison of upper airway anatomical changes during mandibular protrusion and with mandibular advancement device use

目的 研究主动前伸下颌与佩戴下颌前移型口腔矫治器(oral appliance, OA)时上气道各个平面形态结构变化一致性。探讨主动前伸下颌动作时咽腔结构变化可否预估阻塞性睡眠呼吸暂停低通气综合征(obstructive sleep apnea-hypopnea syndrome, OSAHS)患者佩戴OA的气道结构增量。方法 24例成人患者和20例正常对照分别于清醒平静呼吸、主动前伸下颌及佩戴OA时采用MRI获取上气道结构测量指标。比较同一个体主动前伸下颌与佩戴OA状态下,不同咽腔平面咽腔测量参数的变化趋势及程度的差异。分析佩戴OA时气道结构扩大者的临床特征。结果 OSAHS患者呼吸暂停低通气指数(apnea-hypopnea index, AHI) 41.8(15.9,53.5)次/h,睡眠时最低血氧饱和度平均(80.2±9.5)%。前伸下颌与佩戴OA均可显著增大OSAHS和对照组下颌与咽后壁距离(t=-6.853,P<0.001;t=-8.641,P<0.001),主动前伸动作时增幅更显著(P<0.05)。佩戴OA时腭后气道最小截面积、软腭后区咽腔容积较基线状态增大(P<0.05),且较主动前伸下颌动作增幅更大(OSAHS组Z=-2.057,Z=-2.543;对照组Z=-0.201,Z=-2.254)。对照组主动前伸下颌时会厌平面咽腔面积增量更大(Z=2.365),而OSAHS患者佩戴OA会厌平面咽腔面积、舌后气道容积增量更大(Z=-2.236,Z=-2.171)。前伸下颌时会厌水平气道面积变化量[OR=5.489(1.691,17.815)]、软腭后最小截面积变化量[OR=4.589(1.320,15.953)]和AHI[OR=0.935(0.898,0.974)]等因素可预测佩戴OA时腭后区及舌后区咽腔容积增长。结论 主动前伸下颌时上气道结构变化趋势与OA佩戴时一致性较强。但在气道的不同区域的作用幅值存在一定差异。前伸下颌时咽腔面积变化有助于佩戴下颌前移型口腔矫治器能获得结构扩大的个体。

Objective This study aimed to investigate the changes in the upper airway structure during mandibular protrusion and the use of an oral appliance(OA)in patients with obstructive sleep apnea-hypopnea syndrome(OSAHS).Additionally,we explored whether the alterations in the pharyngeal cavity caused by mandibular protrusion could predict structural increment with OA use.Methods Upper-airway MRI was performed on 24 adult patients with OSAHS and 20 controls while awake,during mandibular protrusion,and while wearing an OA.The consistency of anatomical changes in different pharyngeal areas during mandibular protrusion and while wearing an OA was assessed.The characteristics of patients with enlarged retropalatal and retroglossal airways when using an OA were analyzed.Results The apnea-hypopnea index(AHI)of the OSAHS group was 41.8(15.9,53.5)times/h,and the lowest oxygen saturation was(80.2±9.5)%.Both mandibular protrusion and OA use significantly increased the distance between the mandible and the posterior pharyngeal wall in the OSAHS and control groups(t=-6.853,P<0.001;t=-8.641,P<0.001).The increment with mandibular protrusion was more significant than that with OA use(P<0.05).An increased minimum cross-sectional area and volume in the retropalatal area were observed with OA use.Moreover,the increment with mandibular protrusion was more significant than mandibular protrusion(Z=-2.057,Z=-2.543 in the OSAHS group;Z=-0.201,Z=-2.254 in the control group).Compared with OA use,mandibular protrusion caused a greater increment in the epiglottic area in the control group(Z=2.365).Meanwhile,in patients with OSAHS,a greater increment in the epiglottic area and volume of the retroglossal area were observed with OA use(Z=-2.236,Z=-2.171).The following parameters had predictive value for identifying patients who had enlarged retropalatal and retroglossal airways with OA use:changes in the epiglottic cross-sectional area during mandibular protrusion[OR=5.489(1.691,17.815)],changes in the retropalatal airway minimum cross-sectional area during mandibular protrusion[OR=4.589(1.320,15.953)],and the AHI[OR=0.935(0.898,0.974)].Conclusion The changes in the upper airway structure during mandibular protrusion are consistent with those for OA use.However,certain differences in the amplitude of anatomical changes in different regions of the upper airways were noted.The changes in the pharyngeal cavity area during mandibular protrusion may have predictive value for selecting candidates for mandibular advancement device treatment.