Tomas Xavier, Pomes Jaume, Berenguer Juan, Quinto Llorenç, Nicolau Carlos, Mercader Josep Maria, Castro Vicente
Department of Radiology, Hospital Clínic, Facultat de Medicina, Universitat de Barcelona, Villarroel 170, Barcelona 08036, Spain.
Radiographics. 2006 May-Jun;26(3):765-81. doi: 10.1148/rg.263055091.
Temporomandibular joint (TMJ) dysfunction is a common condition that is best evaluated with magnetic resonance (MR) imaging. The first step in MR imaging of the TMJ is to evaluate the articular disk, or meniscus, in terms of its morphologic features and its location relative to the condyle in both closed- and open-mouth positions. Disk location is of prime importance because the presence of a displaced disk is a critical sign of TMJ dysfunction. However, disk displacement is also frequently seen in asymptomatic volunteers, so that other findings may be required to help make the diagnosis. These findings include thickening of an attachment of the lateral pterygoid muscle, rupture of retrodiskal layers, and joint effusion and can serve as indirect early signs of TMJ dysfunction. It is important for the radiologist to detect early MR imaging signs of dysfunction, thereby avoiding the evolution of this condition to its final stage, an advanced and irreversible phase that is characterized by osteoarthritic changes such as condylar flattening or osteophytes. Further studies conducted with the latest MR imaging techniques will allow a better understanding of the sources of TMJ pain and of any discrepancy between imaging findings and patient symptoms.
颞下颌关节（TMJ）功能障碍是一种常见病症，磁共振（MR）成像对其评估效果最佳。TMJ的MR成像第一步是评估关节盘，即半月板，包括其形态特征以及在闭口和开口位时相对于髁突的位置。盘的位置至关重要，因为盘移位是TMJ功能障碍的关键征象。然而，无症状志愿者中也常可见到盘移位，因此可能需要其他表现来辅助诊断。这些表现包括翼外肌附着处增厚、盘后组织层破裂以及关节积液，可作为TMJ功能障碍的间接早期征象。放射科医生检测到功能障碍的早期MR成像征象很重要，从而避免该病症发展到最终阶段，即一个以髁突扁平或骨赘等骨关节炎改变为特征的晚期且不可逆阶段。采用最新MR成像技术进行的进一步研究将有助于更好地理解TMJ疼痛的根源以及成像表现与患者症状之间的任何差异。
