MR imaging of temporomandibular joint abnormalities associated with cervical hyperextension/hyperflexion (whiplash) injuries.

Patients often have temporomandibular joint (TMJ) dysfunction-related symptoms after cervical hyperextension/hyperflexion injuries ("whiplash") caused by rear-end motor-vehicle collisions. To determine abnormalities of the TMJ associated with these injuries, 33 consecutive symptomatic patients (66 joints) with no direct trauma to the jaw, mouth, head, or face due to the accident and no prior history of TMJ dysfunction underwent magnetic resonance (MR) imaging, and the images were retrospectively analyzed. Overall, 29 (88%) patients had some type of TMJ abnormality related to whiplash injury. Displacement of the disk was seen in 37 (56%) of the TMJs as follows: 21 (32%) had anterior displacement with reduction, nine (14%) had anterior displacement without reduction, six (9%) had lateral or medial displacement, and one (2%) had posterior displacement. On T2-weighted images, 43 (65%) TMJs had abnormal joint fluid or edema, predominantly affecting the joint capsule and/or lateral pterygoid muscles. The finding that many of the patients had joint fluid and/or soft-tissue edema indicates that T2-weighted images are especially useful for assessment of patients with a history of whiplash injury.     

Dynamic display of the temporomandibular joint meniscus by using "fast-scan" MR imaging

In order to display temporomandibular joint (TMJ) images as a dynamic or motion study, a protocol was developed to obtain MR images of the TMJ in multiple phases of opening by using the "fast-scanning" capabilities of the GE Signa MR scanner. To facilitate this procedure a prototype device was also developed to passively open the patient's mouth from resting (closed) to fully open in user-defined increments (minimum 1 mm). MR imaging (surface coil) was carried out at each successive station using the GRASS, pulse-sequence data base of the GE Signa system operating at 1.5 T. Image-acquisition parameters were optimized in studies of cadavers and volunteers to obtain the clearest delineation of the TMJ meniscus and to determine any potential tradeoffs between total imaging time per slice (image quality), patient tolerance, and other practical considerations. For viewing, the images were sequentially placed in the video memory of the operating console and displayed in a back-and-forth-closed cine loop or "movie" mode at variable (operator-selectable) speeds. The dynamic sequences in four individuals were compared with static open- and closed-mouth views obtained with routine pulse sequences. Any single image from the dynamic display lacked the high resolution of the routine static images because of technical limitations of the pulse-sequence data base. However, in the movie mode the pertinent joint structures (such as meniscus and condyle) were clearly delineated, as were several of the important muscles of mastication. The anterior motion (translation) of the meniscus during jaw opening is particularly evident and suggests great potential for functional evaluation. These results show the feasibility of dynamic TMJ imaging with MR. The added information of the cine display potentially complements the routine static images and may prove extremely valuable in the assessment of TMJ dysfunction.     

Open-mouth versus closed-mouth radiographs of the nasopharynx in the evaluation of nasopharyngeal airway obstruction

The open-mouth and closed-mouth nasopharyngeal airway radiographs of 53 children, whose symptomatology score was concordant with nasopharyngeal airway obstruction that may be due to adenoidal enlargement, were taken and, for each radiograph, nasopharyngeal airway/soft palate (NA/SP) ratio was measured and graded using the method of Cohen and Konak. According to the statistical analysis, since closed-mouth views correlated better with the symptomatology score than the open-mouth views, if a radiological measurement is needed to evaluate the nasopharyngeal airway obstruction, closed-mouth views can be chosen.     

Fast spin-echo imaging of the temporomandibular joint

The applicability of a fast spin-echo (PSE) technique for magnetic resonance imaging of the tem-poromandibular joint (TMJ) was studied, and the technique compared with a conventional spin-echo (CSE) technique. Sagittal Tl-weighted CSE and dual-echo FSE images of 50 TMJs in 25 patients with symptoms of internal TMJ derangement were compared. CSE and FSE images were diagnostically comparable in 22 TMJs (44%). The FSE technique was rated better than CSE imaging for delineation of the disk in 26 joints (52%), whereas the CSE technique was rated better in only two joints (4%). The FSE technique was preferred overall in 54% of the joints. Mild to moderate joint effusion was detected in 17 joints because additional T2-weighted data were provided with the dual-echo FSE technique. The study showed that FSE imaging is an effective technique for evaluation of the TMJ. It is faster and diagnostically comparable to or better than CSE imaging, with the added advantage of providing T2-weighted data.     

颞下颌关节的开、闭口位计算机三维重建及测量

目的:探讨计算机三维重建技术在颞下颌关节开闭口运动研究中的应用。方法:利用生物塑化技术制作1.0mm厚的闭口位、大开口位的颞下颌关节的薄层断面标本,在SGI工作站上对关节盘、髁突等结构进行三维重建及相关测量。结果:计算机三维重建图像可显示闭口位、大开口位时颞下颌关节形态、位置变化及其三维解剖结构关系。重建结构均能单独显示、任意搭配显示或整体显示,并可绕任意轴进行旋转,任意径线及角度均可适时测量。结论:计算机三维重建技术对于颞下颌关节运动解剖研究具有重要应用价值。     

Temporomandibular joint disk position assessed at coronal MR imaging in asymptomatic volunteers

PURPOSE: To assess the normal position of the temporomandibular joint (TMJ) disk relative to the condyle by using coronal magnetic resonance (MR) imaging in asymptomatic volunteers. MATERIALS AND METHODS: This study was approved by the review committee for human research, and all subjects signed an informed consent form. Thirty symptom-free volunteers without histories of TMJ disorders underwent standardized clinical examinations. Afterward, bilateral sagittal oblique and coronal oblique MR images were acquired with the patient's mouth opened and closed. The coronal oblique opened- and closed-mouth images were analyzed by using computer software. The medial and lateral edges of both the TMJ disk and the condyle were marked for these imaging examinations by using the section through the posterior 3 mm of the disk. To eliminate the effect of different magnifications and/or distortions, the distance between these points was measured automatically and divided by the largest mediolateral dimensions of the condyle. To assess the reliability of the measurements, four observers evaluated the position of the disk in the coronal plane. To assess the changes in position of the posterior 3 mm of the disk in the coronal plane in the closed- and opened-mouth positions, the Wilcoxon signed rank test for matched pairs was used. Interobserver measurement reliability was evaluated by using interclass correlation coefficients (ICCs). RESULTS: Analysis of the coronal closed-mouth disk position revealed a medial position of the TMJ disk relative to the condyle in 11 (21%) of 52 analyzed joints. In the opened-mouth position, the medial location of the disk was more frequent: 29 (85%) of 34 analyzed joints exhibited a medial position of the disk relative to the condyle in this plane. This increasingly medial position of the disk was statistically significant (P < or = .001). Measurement reliability assessment revealed sufficient results (ICC > or = 0.7). CONCLUSION: At both closed- and opened-mouth MR imaging, a medially located TMJ disk seems to be within the normal range of variation. The disk seems to shift even more medially when the mouth is opened.     

中颅窝凹陷度与颈椎张口位环枢关节显示效果的相关性研究

目的探讨中颅窝凹陷度与颈椎张口位X线片环枢关节显示效果的相关性。方法①收集标准颈椎张口位影像200例,同时照有颈椎侧位影像。②中颅窝凹陷度测量方法：在颈椎侧位影像上,连接上颌门齿下缘与枕骨下缘,测量第1、2颈椎间隙到连线的垂直距离,第1、2颈椎间隙位于连线下方的为正值,位于上方的为负值。③张口位影像评价测量方法：在标准张口位影像中,测量环枢关节颈1关节面连线中点到上颌门齿下缘的距离,连线位于上颌门齿下缘上方的为负值,相反的为正值。④评价中颅窝凹陷度测量数值与张口位影像测量数值的相关性。⑤评价中颅窝凹陷度测量数值与颈椎张口位环枢关节显示效果的相关性。结果①中颅窝凹陷度测量数值与张口位影像测量数值存在相关性。②当中颅窝凹陷度测量数值距离〉2 mm时,张口位影像环枢关节显示良好;当距离〈2 mm时,齿状突显示欠佳;而当测量数值接近0或负值时,环枢关节与上颌门齿和枕骨重叠,显示不清。结论中颅窝凹陷度对颈椎张口位影像显示效果具有相关性,当中颅窝凹陷度数值为0或负值时,张口位环枢关节与上颌门齿和枕骨重叠,显示不清。     

Association between high signal intensity in the posterior disc attachment seen on T2 weighted fat-suppressed images and temporomandibular joint pain

OBJECTIVES: We sought to determine whether high signal intensity in the posterior disc attachment (PDA) seen on T2 weighted fat-suppressed MRI is associated with temporomandibular joint (TMJ) pain and joint pathology. METHODS: This study was based on 283 TMJs of 177 patients (31 males and 146 females, mean age 32.7 years) with TMJ disorders showing anterior disc displacement. MRI evaluation included assessment of signal intensity in the PDA and TMJ status (disc displacement with reduction, disc displacement without reduction and disc displacement with bone changes). Clinical criteria that were considered positive indicators of TMJ pain included the presence of pre-auricular pain during palpation, jaw function and assisted or unassisted mandibular opening. Association of signal intensity in the PDA with joint pain and TMJ status was analysed using chi2 test. RESULTS: Joint pain was reported in 47 (77.0%) out of 61 joints with high signal intensity in the PDA and in 97 (43.7%) out of 222 joints with low signal intensity in the PDA (P<0.0001). High signal intensity in the PDA correlated closely with more advanced joint pathology. In joints with anterior disc displacement with bone changes, TMJ pain was more commonly reported in joints with high signal intensity in the PDA than with low signal intensity in the PDA (P<0.0001). CONCLUSIONS: High signal intensity in the PDA on T2 weighted fat-suppressed MRI is associated with TMJ pain in TMJ disorders with anterior disc displacement with bone changes in the mandibular condyles.     

TMJ disorders and pain: assessment by contrast-enhanced MRI

Though magnetic resonance (MRI) is a widely accepted standard for the assessment of patients with temporomandibular joint (TMJ) disorders, efforts to correlate symptoms to MRI findings have often given controversial results. Aim of this study was to investigate the correlation between TMJ pain and findings of contrast-enhanced MRI. Thirty-eight consecutive patients with TMJ dysfunction syndrome (study group) were examined with MRI. Protocol included T2 turbo spin-echo sequence, T1 spin-echo sequence, and T2 gradient-echo (acquired with closed jaw, at intermediate and maximal opening). Post-contrast phase was obtained through a fat sat 3D T1 gradient-echo sequence (VIBE). Post-contrast findings in the study group were matched with those obtained in a control group of 33 patients submitted to MRI of the paranasal sinuses. Statistically significant difference was found between condylar medullary bone enhancement in painful TMJ, in painless TMJ and control group. In addition the average thickness of joint soft tissue enhancement in painful TMJ was superior to painless TMJ (p<0.0001) and to control group. On multivariate logistic regression analysis, the odds ratio that a painful TMJ showed disk displacement, osteoarthrosis, effusion and JST enhancement were 3.05, 3.18, 1.2 and 11.36, respectively. Though not histologically proven, TMJ enhancement could reflect the presence of inflammation in painful joints. Furthermore, the administration of contrast could be of help for the assessment of patients with orofacial pain, particularly when clinical exploration is insufficient to ascribe the pain to TMJ.     

Effects of orthodontic treatment with fixed functional orthopaedic appliances on the disc-condyle relationship in the temporomandibular joint: a magnetic resonance imaging study (Part II)

OBJECTIVES: This study aimed to verify the effects that corrective treatment for skeletal Class II malocclusions with fixed functional orthopaedic appliances has on the relative positions of the articular disc and the mandibular condyle. METHODS: Orthodontic treatment progress was monitored in 20 patients by magnetic resonance imaging (MRI) at four defined points in time. Visual inspection of the temporomandibular joints (TMJs) was performed on three slices each (lateral, central, medial) of closed-mouth and maximum-open parasagittal MRI. Metric analysis was performed on the central slices of the images obtained in the closed-mouth position. To assess the positional relationship in the sagittal dimension between the articular disc and the mandibular condyle, both methods were used. RESULTS: The comparison of pre-treatment and post-treatment findings revealed in none of the joints that the disc-condyle relationship had been adversely affected as a consequence of the treatment. Rather, the outcome was an improved relationship in a total of eight joints. After groups of joints had been defined by disc position, metric analysis revealed a significantly improved positional relationship in those joints in which an anterior disc displacement had been found initially. CONCLUSION: Orthodontic treatment with a rigid, fixed functional appliance to correct skeletal distoclusion results in the following side effects on the disc-condyle relationship in the TMJ: the treatment does not have adverse effects on initially physiological disc-condyle relationships; in TMJs with initial partial or total anterior disc displacement, improved disc position can be achieved.     

颞下颌关节滑膜软骨瘤病的MRI表现

目的:探讨和描述颞下颌关节(TMJ)滑膜软骨瘤病的MRI表现特点。材料和方法:回顾性观察和分析13例经手术病理证实的TMJ区滑膜软骨瘤病的MRI表现。所有病例均在术前行闭口矢状面和冠状面PDWI、开口矢状面T_2WI检查。结果:所有滑膜软骨瘤病均发生于TMJ上腔。病变的MRI表现:关节上腔异常积液(13例,100%);关节囊明显扩张(11例,84.6%);关节腔内有多发软骨样小体的形成(11例,84.6%);关节囊或滑膜组织增厚(8例,61.5%)和颞骨关节面骨质破坏(4例,30.8%)。MRI未显示病变有下颌髁突侵蚀、关节囊外软组织侵犯、大脑颞叶脑膜和脑实质侵犯。结论:颞下颌关节滑膜软骨瘤病的MRI表现具有一定特点,主要表现为关节上腔异常积液,伴关节囊扩张、多发软骨样结节小体形成和滑膜组织增厚。     

Oblique head position in temporomandibular joint arthrography

Thirteen patients were prospectively studied with arthrography to determine whether oblique head positions were helpful in diagnosing internal derangement of the temporomandibular joint (TMJ). After injection of contrast material, inclined transcranial lateral spot films were obtained with the patient's head in upward oblique, downward oblique, and neutral positions. The spot films were analyzed for internal derangement by assessing the size of the mass effect on the arthrogram. Twelve of the 13 arthrograms showed evidence of internal derangement of the TMJ. However, the apparent size of the mass effect varied in different head positions. Each of the three views failed to demonstrate the mass effect in at least one instance (eight different patients). No head position was better than another in demonstrating the mass effect. Thus, oblique head positions are useful adjuncts for diagnosing internal derangement of the TMJ.     

MRI and arthrography in the evaluation of TMJ disorders

Arthrosis of the temporomandibular joint (TMJ) is a noninfectious, noninflammatory condition characterized by joint pain, noise (clicking) and abnormal motion. It contains various disease processes, such as abnormalities in the menisci or masticating muscles, subluxation of the condyle and degenerative joint disease. Analysis of the morphology and dynamics of TMJ by means of imaging modalities has become highly advanced since the development of arthrography in the late 1970s. Magnetic resonance imaging (MRI) has become the modality of choice in the evaluation of TMJ owing to the development of surface coils. We retrospectively studied MRI and inferior joint compartment arthrography in the evaluation of TMJ disorders. Nineteen joints of 14 patients included 15 with internal derangement, two with osteoarthrosis and two normal joints. Sagittal MR images were routinely obtained in a resting position and in positions with the mouth half open, and also with the mouth fully open on balanced images. Although perforation of the menisci was difficult to evaluate, MRI and arthrography were equally useful in identifying the shape and position of the meniscus. However, MRI was more reliable in depicting TMJ abnormalities than arthrography. MR is considered to be the modality of choice in screening arthrosis of TMJ, making the definitive diagnosis of internal derangement and monitoring conservative therapy for arthrosis.     

MR imaging of the temporomandibular joint: a validation experiment in vitro

RATIONALE AND OBJECTIVES: The authors compared magnetic resonance (MR) image quality obtained from 3- and 1-mm-thick sections in the depiction of the temporomandibular joint (TMJ) and its adjacent structures. MATERIALS AND METHODS: Eight TMJ specimens from four adult cadaver heads were depicted with MR imaging. Both 3- and 1-mm-thick sections were generated. One oral and maxillofacial radiologist, who was blinded to section thickness, evaluated the anatomic details of the images. Subsequently, the joints were surgically explored by two oral and maxillofacial surgeons, and the physical findings were recorded. RESULTS: Some statistically significant differences were found between the physical findings and the 3-mm-thick section images, while no significant differences were found with the 1-mm-thick sections. CONCLUSION: The TMJ and its adjacent structures were better depicted by thinner MR images.     

Temporomandibular joint disk displacement: comparison in asymptomatic volunteers and patients

PURPOSE: To compare the prevalence and type of temporomandibular joint (TMJ) disk displacement in asymptomatic volunteers with those in patients. MATERIALS AND METHODS: Bilateral oblique sagittal and oblique coronal intermediate-weighted magnetic resonance (MR) images of the TMJs in 58 patients with pain and dysfunction were analyzed and compared with corresponding MR images of 62 asymptomatic volunteers. RESULTS: Forty-five (78%) of 58 patients had disk displacement compared with 22 (35%) of 62 asymptomatic volunteers. Complete disk displacement was found in 46 (40%) of 115 joints in patients compared with three (2.4%) of 124 joints in asymptomatic volunteers, whereas partial disk displacement occurred in 26 (22.6%) and 27 (21.8%) joints, respectively. Two types of complete disk displacement, anterolateral and anterior, occurred frequently in patients, seldom in volunteers. Only minor differences were found between other types of disk displacement when prevalence in patients was compared with that of volunteers. The disk reduced to a normal position on open-mouth images in all joints in the volunteers compared with 76% of the joints in patients. CONCLUSION: TMJ disk displacement was less prevalent and was of a different type in asymptomatic volunteers compared with patients with pain and dysfunction.     

Clinical significance of increased temporomandibular joint uptake by planar isotope bone scan

Previous studies have suggested a role for the isotope bone scan in the evaluation of patients with temporomandibular joint (TMJ) related symptoms. The studies have not evaluated the frequency or significance of increased TMJ uptake in a random population. One hundred fourteen patients receiving routine bone scans were asked to complete questionnaires regarding TMJ symptoms. The data show that marked TMJ uptake is relatively rare (4%) and correlated with appropriately lateralizing symptoms in all cases. Lesser degrees of increased TMJ uptake correlated poorly (50% symptomatic). The authors suggest that increased TMJ uptake is a significant finding on routine isotope bone scans. The role of the isotope bone scan in the symptomatic patient remains unclear.     

Internal derangements of the temporomandibular joint: findings in the pediatric age group

Findings in 31 pediatric patients with pain and dysfunction of the temporomandibular joint (TMJ) are reported. The average age was 14 years (range, 8-16) and the average duration of symptoms was 21.4 months (range, 3 mo.-5 yr.). Internal derangements were found in 29 patients (94%) and degenerative arthritis in 13 (42%). In 12 patients (39%), the problem could be traced to an injury to the jaw. Secondary condylar hypoplasia was associated with the meniscal abnormality in 3 patients (10%). Further awareness of internal derangements of the TMJ in the pediatric population should permit greater recognition of their etiology. It is important that treatment be initiated as soon as possible, not only to minimize the development of osseous disease in young adults but also to prevent facial growth deformities.     

Temporomandibular joint and 3.0 T pseudodynamic magnetic resonance imaging. Part 2: evaluation of articular disc obscurity

Objectives

This study examined the relationship between temporomandibular joint (TMJ) dysfunctions and obscurity grades of interpreted anterior and posterior borders of the articular disc (Da and Dp, respectively) by 3.0 T pseudodynamic MRI.

Methods

Da and Dp were classified into seven obscurity grades, and the Dp contour was classified into three types. The grades, types and TMJ function were compared by 3.0 T pseudodynamic MRI.

Results

Unobscured Da images at condylar positions posterior to the articular eminence were associated with normal TMJ function (P = 0.046 < 0.05). Unobscured Dp images at condylar positions anterior to the articular eminence were associated with normal TMJ function (P = 0.033 < 0.05). In addition, unobscured Dp images following flap insertion were associated with normal TMJ function (P = 0.043 < 0.05). There was no statistical relationship between Dp contour types and TMJ movement, but any change observed in the Dp contour during mouth opening was associated with abnormal TMJ function (P = 0.040 < 0.05).

Conclusions

Grading of Da and Dp obscurity based on how well the areas were defined in the images, identifying the condylar positions in relation to the glenoid fossa and articular eminences, and observing the changes in Dp contour types were useful for diagnosing TMJ abnormalities.     

MR tomographic diagnosis of internal derangement of the temporomandibular joint]

On the basis of MR imaging studies in 150 temporomandibular joints (TMJ) a classification system for internal derangement of the TMJ was defined. Clinically, internal derangement is characterized by disc displacement and disorders of the mandibular condyle. MR imaging enables a differentiation of early stages (I,II) with disc displacement, the intermediate stage (III), and the later stages (IV,V) with osseous destruction. Optimal diagnostic results (n = 140) allowed the use of proton-density sequences in both open and closed joint positions (TR/TE = 1000/28). Dynamic imaging of the TMJ was performed using fast-gradient echo sequences and a self-developed hydraulic opening device (n = 20). MR imaging has proved to be the method of choice for the pre- and post-therapeutic evaluation of internal derangement of the TMJ.     

超声引导关节腔内注射富血小板血浆治疗颞下颌关节紊乱的疗效分析

【摘要】　目的?评估超声引导下关节腔中注射富小板血浆（PRP）治疗颞下颌关节紊乱病的有效性。方法?2016年4月至2018年4月,门诊诊治45例确诊为颞下颌关节紊乱患者,超声引导将采集于患者自身的PRP注射于患者病变的颞下颌关节腔内。观察患者在治疗前和治疗后1、3和6个月的最大张口度,及颞下颌关节在静息、运动和咀嚼时VAS评分。结果?关节腔内注射PRP可有效改善最大口腔开放程度,颞下颌关节在静息,运动和咀嚼时VAS评分与治疗前相比显著降低。结论?超声引导下关节腔内注射PRP可显著改善颞下颌关节紊乱患者的体征和症状。