健常者および睡眠時無呼吸症候群患者の閉塞性イベント時にマルチディテクターCTで評価した上気道の状態依存性変化

State-dependent changes in the upper airway assessed by multidetector CT in healthy individuals and during obstructive events in patients with sleep apnea.

• Ula Lindoso Passos
• Pedro Rodrigues Genta
• Bianca Fernandes Marcondes
• Geraldo Lorenzi-Filho
• Eloisa Maria Mello Santiago Gebrim

抄録

目的:

閉塞性イベント中の気道狭窄が主に後手口蓋レベルで発生し、側咽頭壁の動的変化と舌の位置の結果に起因するかどうかを決定するために。

OBJECTIVE: To determine whether airway narrowing during obstructive events occurs predominantly at the retropalatal level and results from dynamic changes in the lateral pharyngeal walls and in tongue position.

方法:

重度の閉塞性睡眠時無呼吸症候群（OSA）患者11人と、OSAのない健常者7人を、覚醒時および自然睡眠時に評価した（フルポリソムノグラフィーによる記録）。高速マルチディテクターCTを用いて、覚醒状態と睡眠状態における上気道の画像を得た。

METHODS: We evaluated 11 patients with severe obstructive sleep apnea (OSA) and 7 healthy controls without OSA during wakefulness and during natural sleep (documented by full polysomnography). Using fast multidetector CT, we obtained images of the upper airway in the waking and sleep states.

結果:

睡眠中の上気道狭窄は、OSA群では後口蓋レベルで後口蓋レベルよりも有意に大きく（p＜0.001）、対照群では有意に大きかった（p＜0.05）。後口蓋咽頭気道容積は、OSA群では覚醒時に対照群よりも小さく（p < 0.05）、OSA群の被験者でのみ覚醒から睡眠まで有意に減少した。後口蓋咽頭狭窄は、前後径（p = 0.001）および側方径（p = 0.006）の減少に起因し、これはそれぞれ、側方咽頭壁容積（p = 0.001）および舌後変位（p = 0.001）の増加と相関していた。睡眠中の後咽頭狭窄は、OSA群の被験者では発生しなかった。

RESULTS: Upper airway narrowing during sleep was significantly greater at the retropalatal level than at the retroglossal level in the OSA group (p < 0.001) and in the control group (p < 0.05). The retropalatal airway volume was smaller in the OSA group than in the control group during wakefulness (p < 0.05) and decreased significantly from wakefulness to sleep only among the OSA group subjects. Retropalatal pharyngeal narrowing was attributed to reductions in the anteroposterior diameter (p = 0.001) and lateral diameter (p = 0.006), which correlated with an increase in lateral pharyngeal wall volume (p = 0.001) and posterior displacement of the tongue (p = 0.001), respectively. Retroglossal pharyngeal narrowing during sleep did not occur in the OSA group subjects.

結論:

OSA患者では、睡眠中の上気道の狭窄は、主に後口蓋レベルで発生し、前後側と側方の寸法に影響を与え、側方咽頭壁の拡大と後舌の変位と関連しています。

CONCLUSIONS: In patients with OSA, upper airway narrowing during sleep occurs predominantly at the retropalatal level, affecting the anteroposterior and lateral dimensions, being associated with lateral pharyngeal wall enlargement and posterior tongue displacement.