关节盘无移位的症状性颞下颌关节的核磁共振研究

目的：本研究的目的是应用核磁共振成像（MRI）诊断颞下颌关节紊乱病（TMD），讨论在关节盘位置正常的TMD关节中的核磁共振影像发现，并探讨这些影像发现与临床症状间的关系。方法：本研究对2000－2002年期间在芬兰欧鲁大学牙学院颌面外科就诊的78名TMD患中，经MRI发现为关节盘位置正常的68侧关节作了影像及临床症状的对比分析。结果：在此68侧关节MRI中，发现了髁突运动异常：过度运动（61.8%）及运动受限（2.9%）；发现了怀疑为翼外肌上头和／或下头的肥大、萎缩及挛缩等病理改变（58.9%）。在关节盘形态方面，未发现明显的关节盘畸形，但发现了关节盘整体变厚的病理影像表现（22.1%），还到涉及关节囊上腔、下腔和／或双板区的炎性渗出（35.3%）。髁突过度运动及翼外肌病理改变与症状组有显性关系。结论：本研究的结果提示，髁突过度运动及可能发生的翼外肌病理改变，在引起关节盘位置正常的颞下颌关节的临床TMD症状中，扮有十分重要的角色。

MRI findings in TMD patients with disc in normal position

Objective: The aim of this study is to diagnose Temporomandibular Disorder (TMD) by Magnetic ResonanceImaging (MRI) and to discuss the relationship between the findings of MRI and the clinical symptoms in patients withTMD with disc in normal position. Methods: 78 patients were diagnosed as TMD in Department of Oral and MaxillofacialSurgery, Institute of Dentistry, Unversity of Oulu. Disc position was found as in normal position in 68 joints. Mobility ofthe condyle, pathological changes of the lateral pterygoid muscle, deformity of the disc and effusion of the joint wereevaluated in MRI. Results: In 68 joints, hypermobility of the condyle were found in 42 joints (61.8%), hypomobility of thecondyle in 2 joints (2.9%). Pathological changes of the lateral pterygoid muscle were noticed in 40 joints (58.8%).Thickness of disc (15 joints, 22.1%) and effusion of joint (24 joints, 35.3%) were also detected in MRI. Among thesefindings, hypermobility of the condyle and pathological changes of the lateral pterygoid muscle showed close associationwith the clinical symptoms of TMD (P<0.01). Conclusion: The results of this study indicated that hypermobility of thecondyle and pathological changes of the lateral pterygoid muscle may play important roles in giving rising to the clinicalsymptoms of TMD.