Department of Dentistry, National Taiwan University Hospital, Taipei, Taiwan.
Department of Physical Medicine and Rehabilitation and Community and Geriatric Research Center, National Taiwan University Hospital, Taipei, Taiwan.
Ann Med. 2023;55(2):2261116. doi: 10.1080/07853890.2023.2261116. Epub 2023 Oct 4.
Sonoelastography has been increasingly used for non-invasive evaluation of the mechanical features of human tissues. The interplay between orofacial pain and regional muscle activity appears clinically paramount, although only few imaging studies have investigated this association. Using shear wave sonoelastography (SWS), this study ascertained whether orofacial pain induced alterations in the stiffness of superficial and deep masticatory muscles.
All participants were systematically evaluated for oral/facial-related conditions, including the area and intensity of pain. SWS was applied to measure the stiffness of the bilateral masseter, temporalis, and lateral pterygoid muscles. The association between orofacial pain and muscle stiffness/thickness was investigated using a generalized estimating equation for adjusting the influence of age, sex, laterality, and body mass index on muscle thickness/stiffness.
A total of 98 participants were included in the present study: 48 asymptomatic controls, 13 patients with unilateral pain, and 37 patients with bilateral orofacial pain. The reliability, quantified by the intraclass correlation coefficient for muscle stiffness measurement, ranged from 0.745 to 0.893. Orofacial pain at the individual muscle level was significantly associated with masseter muscle stiffness. A trend of increased stiffness ( = 0.06) was also observed in relation to the painful side of the temporalis muscle. No significant correlation was identified between the numeric rating scales for pain and stiffness measurements.
SWS provides reliable stiffness measurements for the superficial and deep masticatory muscles. The ipsilateral masseter and temporalis muscles might be stiffer than those on the side without orofacial pain. Future studies using the present sonoelasotography protocol can be designed to investigate the stiffness changes in the target muscles after interventions.
超声弹性成像技术已越来越多地用于评估人体组织的机械特性的非侵入性方法。口颌面部疼痛与区域肌肉活动之间的相互作用在临床上似乎至关重要，尽管只有少数影像学研究调查了这种关联。本研究使用剪切波超声弹性成像（SWS）来确定口颌面部疼痛是否会改变咀嚼肌的浅层和深层的硬度。
所有参与者均系统评估了口腔/面部相关疾病，包括疼痛区域和强度。使用 SWS 测量双侧咀嚼肌（咬肌、颞肌和翼外肌）的硬度。使用广义估计方程调整年龄、性别、侧别和体重指数对肌肉厚度/硬度的影响，研究口颌面部疼痛与肌肉硬度/厚度之间的关系。
本研究共纳入 98 名参与者：48 名无症状对照者、13 名单侧疼痛患者和 37 名双侧口颌面部疼痛患者。肌肉硬度测量的组内相关系数（ICC）量化了可靠性，范围为 0.745 至 0.893。个体肌肉水平的口颌面部疼痛与咬肌硬度显著相关。颞肌疼痛侧的硬度也呈现增加的趋势（ = 0.06）。疼痛评分和硬度测量之间没有显著相关性。
SWS 为咀嚼肌的浅层和深层提供了可靠的硬度测量。与无口颌面部疼痛的一侧相比，同侧咬肌和颞肌可能更硬。可以使用本超声弹性成像方案设计未来的研究，以调查干预后目标肌肉的硬度变化。
