The effect of quality of temporomandibular joint MR images on interrater agreement

Introducing a novice-friendly classification system for magnetic resonance imaging of the temporomandibular joint disc morphology

OBJECTIVE

To introduce a new classification, aiming to correspond TMJ disc configuration with diagnosis, meanwhile reduce difficulty and subjectivity in TMJ MRI evaluation and training of TMD diagnosis for dental students.

METHODS

90 patients sought for TMD treatment were enrolled in the study, whose MRIs were used to establish the new classification. A total of 180 discs were evaluated using MRI for position (normal, DDWR or DDWoR) and classified by morphology according to previous (Murakami's classification) and new classification respectively. 60 discs were selected and judged by two groups (2 TMJ specialists and 30 dental students) to assess the reliability and validity of the new classification. Questionnaires were acquired for all observers to assess the attitude toward two classification systems. Descriptive statistics, Spearman's rank correlation coefficient, and intraclass correlation coefficient were performed. P < 0.05 was considered statistically significant.

RESULTS

In the new classification, Class 1 disc was significantly correlated with DDWR and Class 3 disc was significantly correlated with DDWoR. Interobserver reliability/consistency for observers between TMJ specialists was 0.867 when Murakami's classification was applied and 0.948 when the new classification was applied. Interobserver ICC value for dental students was 0.656 when using Murakami's classification, and 0.831 when using the new classification. The difference in attitude toward different classification systems was statistically significant.

CONCLUSION

A new classification of TMJ disc configuration is presented. The correlation between disc morphology and position revealed helps diagnosis and management. The new classification improves TMJ MRI interpreting accuracy and provides a better learning and using experience.

Diagnostic value of dynamic magnetic resonance imaging of temporomandibular joint dysfunction

Background

To estimate the diagnostic value of dynamic magnetic resonance imaging (MRI) for the assessment of the temporomandibular joint (TMJ) compared to standard static MRI sequences in patients with TMJ dysfunction (TMD).

Methods and materials

This retrospective study included 71 patients with clinical diagnose of TMD. We acquired 5 static T1- and T2-weighted sequences in parasagittal and paracoronal views and one dynamic sequence (trueFISP) in parasagittal view for each TMJ. Image analysis included evaluation of morphology and function of intra-articular structures and rating of the dynamic images as more, equally, or less informative compared to static MRI sequences.

Results

Mean age was 35.0 ± 14.7 years and 50/71 (70.4%) were female. 127/142 (89.4%) TMJs were of diagnostic quality. 42/127 (33.1%) TMJs showed no disc displacement (DD), 56 (44.1%) had DD with disc reduction (DDwR), and 29 (22.8%) had DD without disc reduction (DDwoR). In 38/127 (29.9%) TMJs, dynamic images were rated “more informative”, in 84/127 (66.2%) “equally informative”, and in 5/127 (3.9%) “less informative” compared to solely static images. Overall, 27/71 (38.0%) patients benefited from additional dynamic sequences compared to solely static images. Dynamic images were “more informative” in TMJs with DDwR (23/56 [41.1%], p < 0.001) and in TMJs with DDwoR (13/29 [44.8%], p = 0.007), while it had no beneficial value for TMJ without DD. For evaluation of joint effusion, static T2-weighted images were rated better in 102/127 (80.3%) TMJs compared to dynamic images (<0.001).

Conclusion

Dynamic MRI sequences are beneficial for the evaluation of morphology and function of the TMJ compared to static sequences, especially in patients with temporomandibular disc displacement.

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Dynamic MRI sequences allow direct observation of the joint`s movements.

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Patients with known or suspected disc displacement benefit the most.

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Dynamic MRI is a sensible addition to solely static images.

Does Incidence of Temporomandibular Disc Displacement With and Without Reduction Show Similarity According to MRI Results?

Purpose

The aim of this study is to assess MRI reports of the patients and to provide retrospective analysis by conducting detailed evaluation of temporomandibular disc position.

Patients and Methods

MRI images of 259 patients from 2008 to 2017 were reviewed retrospectively. Existence of disc displacement in joint with and without reduction, existence of effusion in joint gap, arthritis, degenerative changes in joints and limitation of movement of joint and anatomic characteristics were evaluated.

Results

One hundred and seventeen (45.2%) of the patients had healthy joint connection bilaterally. Anterior disc displacement was observed in 101 (38.9%) of the patients. The number of the patients having disc displacement with reduction was 50 (19.3%) and without reduction was 51 (19.6%) similarly.

Conclusion

The incidence of anterior disc displacement with or without reduction was similar; besides this, the majority of the patients diagnosed with anterior disc displacement were unilateral.

The value of MRI in patients with temporomandibular joint dysfunction: Correlation of MRI and clinical findings

AIM

To estimate the correlation between the MRI findings and clinical outcomes in patients with temporomandibular joint dysfunction (TMD).

METHODS AND MATERIALS

We included 546 female and 248 male patients who were clinically diagnosed with TMD (mean age 38.7 years) and examined by MRI (T1 and T2 weighted images, parasagittal and paracoronal slices). A questionnaire, radiological, and clinical findings were analysed for statistically significant correlations. The analysed parameters included gender, age, disk position, joint degeneration, arthralgia, mouth opening, condyle position and clinical progress.

RESULTS

Of all TMJ's 62% showed physiological disc position, 35% anterior and 3% posterior disc position. Modification of therapy occurred in 20% and alteration of diagnosis was found in 32% of all cases. Anterior disc displacement with reduction showed a specificity of 88% and a sensitivity of 78%, whereas anterior disc displacement without reduction showed a specificity of 84% and a sensitivity of 73%. A significant correlation between disc length, condyle morphology and disc displacement was found. With the increase of intra-articular liquid as seen on MRI the level of arthralgia significantly rose as opposed to mouth opening.

CONCLUSION

Specificity and sensitivity, for anterior disc displacement and osseous changes in TMJ were highly acceptable. Results had confirmed the diagnostic capability of MRI in diagnostic imaging of TMJ. Additionally MRI should be used primarily in severe, therapy-resistant cases and for surgical planning purposes.

Temporomandibular joint (TMJ) disc position in patients with TMJ pain assessed by coronal MRI

OBJECTIVES

To assess the position of the temporomandibular joint (TMJ) disc in patients with TMJ pain and compare it with equivalent published data of asymptomatic volunteers.

METHODS

The oblique coronal closed- and open-jaw MR images from 66 patients with TMJ pain were evaluated. Clinical examination followed the research diagnostic criteria for temporomandibular disorders. In all coronal images, the transverse condylar axis and the medial and lateral edges of the disc were determined using special software. Inter-rater agreement was calculated [two raters; inter-rater correlation coefficient (ICC)]. The presence of osteoarthrosis (OA) was determined by two independent raters. The influence of OA was estimated in patients (generalized estimation equation model). The results were compared with those of healthy volunteers (t-test). Differences between closed and open jaw in patients were analysed with the Wilcoxon matched-pair test.

RESULTS

The ICC was good for the transverse condylar axis (0.987) and the medial edge of the disc (0.799) and fair for the lateral edge (0.355). On average, the disc projected 5.5% to the medial side; laterally, the condyle was partially uncovered by the disc (-16.6%). In the open-jaw position, both the medial and the lateral edges shifted medially (to 17.6% vs -23.6%, Wilcoxon matched-pair test, p < 0.001). OA had no significant influence (generalized estimation equation model, p = 0.952). The disc position differed significantly from asymptomatic individuals (t-test, p < 0.001) who showed a medial disc position and full coverage of the condyle.

CONCLUSIONS

In patients with TMJ pain, the disc seems to be smaller and located less medially than in healthy volunteers. The extent of the medial shift on opening was similar.

Web-based calibration of observers using MRI of the temporomandibular joint

OBJECTIVES

Research diagnostic criteria for temporomandibular disorders (RDC/TMDs) were proposed in 1992 with the aim of standardizing and testing methods for diagnosing TMDs. RDC/TMDs have so far been lacking standardized methods for imaging and criteria for imaging diagnosis of disorders of the temporomandibular joint (TMJ). Criteria for disorders of the TMJ have recently been proposed for MRI. The aim of this study was to publish MR images of the TMJ on the web and to test the agreement of five observers using the criteria.

METHODS

20 cases of MRI of the TMJ were published on the web together with the criteria. The MR images were taken in closed and open mouth positions, and sagittal and coronal views. Five observers diagnosed disc position, disc shape, joint effusion and loose calcified bodies in the TMJ.

RESULTS

In all cases except one, three or more observers agreed upon the diagnosis. All agreed on whether a loose calcified body was present or not. The second best agreement was obtained for disc position in the sagittal view, where all observers agreed in 16 of the 20 cases. For disc position in the coronal view and the evaluation of the disc shape, observer agreement was lower.

CONCLUSION

Criteria were useful in order to standardize and simplify evaluation and thereby probably increase the diagnostic outcome among different observers for MRI of the TMJ. We recommend that the criteria be used internationally to facilitate comparisons between different studies.

Evaluation of the reproducibility in the interpretation of magnetic resonance images of the temporomandibular joint

OBJECTIVES

The aim was to determine the intra- and interexaminer reproducibility in the interpretation of MRI of the temporomandibular joint among independent observers, with respect to six specific articular characteristics, and to discover which of these had greater and lesser agreement.

METHODS

30 magnetic resonance examinations of temporomandibular joints of adults were independently interpreted by 9 experienced and trained observers at 2 different times. Observers were divided into three groups according to their specialties: surgeon dentists specialized in temporomandibular dysfunction and orofacial pain, surgeon dentists specialized in radiology and medical doctors specialized in radiology. The reproducibility analysis was carried out using Cohen's kappa coefficient.

RESULTS

The interexaminer reproducibility ranged from slight to fair. The intraexaminer reproducibility ranged from slight to no agreement. In the interexaminer evaluation, anterior disc displacement without reduction presented greater agreement, whereas change in condylar head shape showed the poorest agreement. In the intraexaminer evaluation, anterior disc displacement without reduction presented slight agreement, whereas, for the other characteristics, no agreement was observed.

CONCLUSION

Examiners do not demonstrate reproducibility in the interpretation of MRI of temporomandibular joints. Therefore, more efforts are necessary with respect to understanding the changes that may be detected in these images in terms of diagnosis and appropriate treatment approaches.

Research diagnostic criteria for temporomandibular disorders (RDC/TMD): development of image analysis criteria and examiner reliability for image analysis

OBJECTIVE

As part of the Multisite Research Diagnostic Criteria For Temporomandibular Disorders (RDC/TMD) Validation Project, comprehensive temporomandibular joint diagnostic criteria were developed for image analysis using panoramic radiography, magnetic resonance imaging (MRI), and computerized tomography (CT).

STUDY DESIGN

Interexaminer reliability was estimated using the kappa (kappa) statistic, and agreement between rater pairs was characterized by overall, positive, and negative percent agreement. Computerized tomography was the reference standard for assessing validity of other imaging modalities for detecting osteoarthritis (OA).

RESULTS

For the radiologic diagnosis of OA, reliability of the 3 examiners was poor for panoramic radiography (kappa = 0.16), fair for MRI (kappa = 0.46), and close to the threshold for excellent for CT (kappa = 0.71). Using MRI, reliability was excellent for diagnosing disc displacements (DD) with reduction (kappa = 0.78) and for DD without reduction (kappa = 0.94) and good for effusion (kappa = 0.64). Overall percent agreement for pairwise ratings was >or=82% for all conditions. Positive percent agreement for diagnosing OA was 19% for panoramic radiography, 59% for MRI, and 84% for CT. Using MRI, positive percent agreement for diagnoses of any DD was 95% and of effusion was 81%. Negative percent agreement was >or=88% for all conditions. Compared with CT, panoramic radiography and MRI had poor and marginal sensitivity, respectively, but excellent specificity in detecting OA.

CONCLUSION

Comprehensive image analysis criteria for the RDC/TMD Validation Project were developed, which can reliably be used for assessing OA using CT and for disc position and effusion using MRI.

Validity of temporomandibular disorder examination procedures for assessment of temporomandibular joint status

INTRODUCTION

This hypothesis-generating study was performed to determine which items in the Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD) and additional diagnostic tests have the best predictive accuracy for joint-related diagnoses.

METHODS

One hundred forty-nine TMD patients and 43 symptom-free subjects were examined in clinical examinations and with magnetic resonance imaging (MRI). The importance of each variable of the clinical examination for correct joint-related diagnosis was assessed by using MRI diagnoses. For this purpose, "random forest" statistical software (based on classification trees) was used.

RESULTS

Maximum unassisted jaw opening, maximum assisted jaw opening, history of locked jaw, joint sound with and without compression, joint pain, facial pain, pain on palpation of the lateral pterygoid area, and overjet proved suitable for distinguishing between subtypes of joint-related TMD. Measurement of excursion, protrusion, and midline deviation were less important.

CONCLUSIONS

The validity of clinical TMD examination procedures can be enhanced by using the 16 variables of greatest importance identified in this study. In addition to other variables, maximum unassisted and assisted opening and a history of locked jaw were important when assessing the status of the TMJ.

The efficacy of magnetic resonance imaging in the diagnosis of degenerative and inflammatory temporomandibular joint disorders: a systematic literature review

OBJECTIVE

To evaluate the evidence for the efficacy of magnetic resonance imaging (MRI) in the diagnosis of disk position and configuration, disk perforation, joint effusion, and osseous and bone marrow changes in the temporomandibular joint.

STUDY DESIGN

A PubMed literature search with specific indexing terms and a hand search were made. Two reviewers assessed the level of evidence of relevant publications as high, moderate, or low. Based on this, the evidence grade for diagnostic efficacy was rated as strong, moderately strong, limited, or insufficient.

RESULTS

The literature search yielded 494 titles, of which 22 were relevant. No publication had a high level of evidence, and 12 had moderate and 10 low levels of evidence. The evidence grade for diagnostic efficacy expressed as sensitivity, specificity, and predictive values was insufficient.

CONCLUSION

That evidence is insufficient emphasizes the need for high-quality studies on the diagnostic efficacy of MRI, incorporating accepted methodologic criteria.

[Temporomandibular joint: MRI diagnostics]

MRI of the temporomandibular joint (TMJ) requires 1.5 T. The radiologist must be familiar with the anatomy and pathology of the TMJ. This review gives a description of MRI protocols for the TMJ, and MRI anatomy and pathology of the TMJ (open and closed mouth) by means of MR images and drawings. Diagnosing of the TMJ related diseases depends on standardized clinical and MR examinations. Therefore close interdisciplinary cooperation between dentist and radiologist is necessary.