Kuroda Migiwa, Otonari-Yamamoto Mika, Araki Kazuyuki
Division of Radiology, Department of Oral Diagnostic Sciences, Showa University School of Dentistry, 2-1-1 Kitasenzoku, Oota-ku, Tokyo, 145-8515, Japan.
Department of Oral and Maxillofacial Radiology, Tokyo Dental College, 2-1-14 Misakichyo, Chiyoda-ku, Tokyo, 101-0061, Japan.
Oral Radiol. 2018 Jan;34(1):17-23. doi: 10.1007/s11282-017-0272-1. Epub 2017 Mar 27.
Pathological changes of the lateral pterygoid muscle (LPM) have been investigated using various modalities, including magnetic resonance (MR) imaging and electromyography. Fluid-attenuated inversion recovery (FLAIR) is an MR sequence that we hypothesized can be used to evaluate abnormalities of the LPM. The purpose of this study was to analyze the FLAIR signal intensity of the LPM in painful temporomandibular joints (TMJs) and investigate the pathological changes of the muscle.
The study was based on 149 TMJs of 77 patients who were referred for MR imaging of the TMJ. Patients rated their degree of pain during chewing and mouth opening using a visual analog scale (VAS). Regions of interest were placed over the superior and inferior heads of the LPM and gray matter on FLAIR sagittal images. Using the signal intensity of gray matter as a reference, the signal intensity ratio (SIR) of the LPM was calculated. Spearman's rank-correlation coefficient was used to analyze the correlation between the SIR and the VAS score (p < 0.05).
A significant correlation was present between the SIR on FLAIR images and the VAS score.
These results suggest that the FLAIR signal intensity of the superior and inferior heads of the LPM significantly increases as TMJ pain becomes more severe. Thus, FLAIR could be useful in assessing the relationship between the MR signals of the LPM and clinical symptoms.
已使用包括磁共振（MR）成像和肌电图在内的各种方法研究了翼外肌（LPM）的病理变化。液体衰减反转恢复（FLAIR）是一种MR序列，我们推测其可用于评估LPM的异常情况。本研究的目的是分析疼痛性颞下颌关节（TMJ）中LPM的FLAIR信号强度，并研究该肌肉的病理变化。
本研究基于77例因TMJ的MR成像而转诊的患者的149个TMJ。患者使用视觉模拟量表（VAS）对咀嚼和张口时的疼痛程度进行评分。在FLAIR矢状位图像上，将感兴趣区域置于LPM的上下头以及灰质上。以灰质的信号强度为参照，计算LPM的信号强度比（SIR）。采用Spearman等级相关系数分析SIR与VAS评分之间的相关性（p < 0.05））。
FLAIR图像上的SIR与VAS评分之间存在显著相关性。
这些结果表明，随着TMJ疼痛加剧，LPM上下头的FLAIR信号强度显著增加。因此，FLAIR在评估LPM的MR信号与临床症状之间的关系方面可能有用。
