咀嚼筋の寿命における形態学的軌跡:横断的高解像度MRI研究
The Journal of craniofacial surgery
|January 26, 2026
まとめ
咀嚼筋(MMT)は若年期に急速に成長し、成人期に安定しますが、30歳以降、特に側頭筋と咬筋で厚さが低下します。これらのMMTの変化は、老化の理解に役立ちます。
科学分野:
- 解剖学; 生体医工学; 放射線学
背景:
- 咀嚼筋(MMT)は下顎機能に不可欠です。MMTは、加齢関連状態の潜在的なバイオマーカーとして注目されています。特に側頭筋以外のMMTについては、寿命を通じた形態学的データは限られています。
研究 の 目的:
- 人間の寿命を通じたMMTの発達軌跡を特徴づけること。MMTの両側対称性、性差、および比較形態学を評価すること。MMTを臨床バイオマーカーとして参照データを提供すること。
主な方法:
- 高解像度3.0T MRIを211人の被験者(年齢1〜87歳)に使用しました。4つのMMTの両側形態測定値(長さ、幅、厚さ)を測定しました。LOESS回帰とBland-Altman分析により、加齢関連トレンドと対称性を評価しました。
主要な成果:
- MMTは小児期/青年期に急速な成長を示し、25〜30歳でピークに達しました。成人期の筋長と幅は安定していました。厚さは30歳以降、特に60歳以降に進行性に低下しました。高い両側対称性が観察され、思春期に性差が現れました。
結論:
- MMTの形態は明確な寿命の軌跡を示し、厚さが最も年齢に敏感なパラメータです。側頭筋と咬筋は、翼突筋とは異なり、有意な加齢に伴う厚さの低下を示します。本研究の結果は、MMT測定値を臨床バイオマーカーとして支持しており、側頭筋の厚さ以外のパラメータの考慮を提案しています。
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