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.

Prospective and controlled study of ophthalmopathy after radioiodine therapy for Graves' hyperthyroidism.

The effects of radioiodine (131I) therapy for hyperthyroidism on the ocular process of Graves' disease is controversial. In order to evaluate the outcome of ophthalmopathy after radioiodine therapy for thyrotoxicosis we studied prospectively 30 Graves' hyperthyroid patients, 22 submitted to radioiodine (131I) treatment (group A) and 8 treated with antithyroid drugs (group B). All patients were evaluated by clinical ophthalmologic examination, and ocular proptosis (OP) was measured with both a Hertel exophthalmometer (HE) and computed tomography (CT) before and 4 to 7 months after therapy. No statistical difference was obtained between pre- and post-treatment OP measurements in each eye in either group, and we did not observe worsening in the ophthalmopathy of patients treated with drugs or radioiodine. After therapy, there was an improvement in the clinical signs of ophthalmopathy in 59% of group A and in 37.5% of group B patients. We found a significant correlation between OP measured by HE and by CT. CT findings showed an increase in orbital fat and/or muscle thickening in all patients at baseline, proving to be a useful procedure for ophthalmologic diagnosis in doubtful cases. No patient in either group developed hypothyroidism or elevated TSH levels during the study period; this may explain our good results in the evolution of Graves' ophthalmopathy after treatment with 131I and antithyroid drugs. Euthyroidism seems to be an important factor in the outcome of ophthalmopathy after therapy, whatever the mode of treatment chosen to achieve it.