Evaluation of the lateral pterygoid muscle using magnetic resonance imaging

Objectives: The aims of this study were to evaluate the visibility of the lateral pterygoid muscle (LPM) in temporomandibular joint (TMJ) images obtained by MRI, using different projections and to compare image findings with clinical symptoms of patients with and without temporomandibular disorders (TMD). Methods: In this study, LPM images of 50 participants with and without TMDs were investigated by MRI. The images of the LPM in different projections of 100 TMJs from 35 participants (70 TMJs) with and 15 participants (30 TMJs) without clinical signs and symptoms of TMD were visible and analysed. Results: The oblique sagittal and axial images of the TMJ clearly showed the LPM. Hypertrophy (1.45%), atrophy (2.85%) and contracture (2.85%) were the abnormalities found in the LPM. TMD signs, such as hypermobility (11.4%), hypomobility (12.9%) and disc displacement (20.0%), could be seen in TMJ images. Related clinical symptoms, such as pain (71.4%), articular sounds (30.4%), bruxism (25.7%) and headache (22.9%), were observed. Conclusions: Patients with TMD can present with alterations in the LPM thickness. Patients without TMD also showed alterations, such as atrophy and contracture, in TMJ images. Recognition of alterations in the LPM will improve our understanding of clinical symptoms and pathophysiology of TMD, and may lead to a more specific diagnosis of these disorders. Dentomaxillofacial Radiology (2010) 39, 494-500. doi: 10.1259/dmfr/80928433

Comparison between computed tomography and clinical evaluation in tumour/node stage and follow-up of oral cavity and oropharyngeal cancer

Objectives: The aim was to verify the concordance of CT evaluation among four radiologists (two oral and maxillofacial and two medical radiologists) at the TN (tumour/node) stage and in the follow-up of oral cavity and oropharyngeal cancer patients. The study also compared differences between clinical and CT examinations in determining the TN stage. Methods: The following clinical and tomographic findings of 15 non-treated oral cavity and oropharyngeal cancer patients were compared: tumour size, bone invasion and lymph node metastases. In another 15 patients, who had previously been treated, a clinical and tomographic analysis comparison for the presence of tumoural recurrence, post-therapeutic changes in muscles and lymph node metastases was performed. The concordances of tomographic evaluation between the radiologists were analysed using the kappa index. Results: Significant agreement was verified between all radiologists for the T stage, but not for the N stage. In the group of treated patients, CT disclosed post-therapeutic changes in muscles, tumour recurrence and lymph node metastases, but no concordance for the detection of lymph node metastases was found between radiologists. In the first group, for all radiologists, no concordance was demonstrated between clinical and tomographic staging. CT was effective for delimitating advanced lesions and for detecting lymph node involvement in N0 stage patients. CT revealed two cases of bone invasion not clinically detected. Conclusions: Interprofessional relationships must be stimulated to improve diagnoses, and to promote a multidisciplinary approach to oral cavity and oropharyngeal cancer. Although CT was important in the diagnosis and follow-up of cancer patients, differences between medical and dental analyses should be acknowledged. Dentomaxillofacial Radiology (2010) 39, 140-148. doi: 10.1259/dmfr/69910245