应用磁共振评估腭咽结构与功能的进展

Research progress in evaluating velopharyngeal structures and functions by magnetic resonance imaging

正常发育的腭咽部结构是获得良好的腭咽闭合功能的关键。在对腭咽闭合功能和正常发音的评估中,有多种仪器可用于检测和辅助诊断腭咽闭合功能不全。过去对腭咽闭合的评估常常使用二维影像学手段进行观察或者仅仅依赖于语音师的主观评估。随着科学技术的发展,磁共振作为一种理想的检查手段逐渐被广泛应用于腭咽结构与功能的评估中。本文从腭咽闭合功能评估的现状与局限性,以及近年来使用的静态磁共振、动态磁共振、三维重建磁共振和扩散张量磁共振成像技术对腭咽部结构与功能的研究进行综述,探讨磁共振成像技术在评估腭咽结构与功能中的作用及意义。文献复习结果显示:静态磁共振成像扫描方式简单,参数便于调节,能较清楚地显示静息状态下或短暂发声状态下腭咽部的解剖结构。动态磁共振成像可以在较为复杂的发音状态下对腭咽部的解剖结构变化进行捕获,获得准确的腭咽闭合过程的动态图像以用于语音病理学的研究。三维重建磁共振成像通常应用于静息状态下的腭咽结构精细扫描,虽然耗时较长,但获得的图像清晰可靠,可进行三维重建分析及三维有限元分析,并对手术的效果评价和手术方式的设计提供帮助。扩散张量成像是通过对肌肉内水分子的运动轨迹来对肌肉的收缩功能进行观测,是一种全新的手段,可以对组成腭咽闭合功能的诸多肌肉进行分析研究。

Normal development of the velopharyngeal structures is key to obtaining good velopharyngeal closure. In the assessment of velopharyngeal closure and normal pronunciation, a variety of instruments can be used to detect and assist in the diagnosis of velopharyngeal dysfunction. In the past, the assessment of velopharyngeal closure often used twodimensional imaging or relied solely on the subjective assessment of the phonetician. With the development of science and technology, magnetic resonance imaging(MRI) has become widely used in the evaluation of velopharyngeal structures and functions as an ideal examination method. This article reviews the current capabilities and limitations in evaluating velopharyngeal closure, as well as recent research on the structures and functions of the velopharyngeal using static MRI, dynamic MRI, threedimensional MRI reconstructions and diffusion tensor imaging(DTI) techniques;in addition, this work explores the role and significance of MRI technology in evaluating the structures and functions of the velopharyngeal. A review of the literature shows that static MRI is simple in terms of the scanning mode, has easily adjustable parameters, and clearly shows the anatomical structures of palatopharyngeal in resting or transient vocal states.Dynamic MRI can capture the anatomical changes of the palatopharyngeal in a more complex pronunciation state and obtain accurate dynamic images of the velopharyngeal closure process for the study of speech pathology. Threedimensional MRI reconstructions are usually used in fine scanning of the velopharyngeal structures in a resting state;although this method takes a long time, the images obtained are clear and reliable. This approach can be used for threedimensional reconstruction analysis and threedimensional finite element analysis, and it can be used to help plan an operation and evaluate the effect of the surgery. DTI is a new method for observing the contractile function of muscles by observing the locus of water molecules in muscles. DTI can be used to analyze and study many muscles involved in velopharyngeal closure.