THYROIDAL OPHTHALMOPATHY - CLINICOTOMOGRAPHIC STUDY

BACKGROUND: To evaluate exophthalmos by Hertel exophthalmometer (HE) c ompared to computed tomography (CT), and extraocular muscle width on C T and its relation with the clinical course in patients with thyroidal ophthalmopathy. METHODS: On reviewed 118 orbits from 59 patients (50 women, mean age 40,6 y., range 12-84) who suffered a thyroidal ophthal mopathy (Graves' disease, n = 57; Hashimoto's tiroiditis, n = 2). Musc le width was evaluated using coronal and mid-axial scans in all cases. Medial rectus (MR) width was analysed by Hallin and Feldon technique. RESULTS: Exophthalmos by HE was 22.5 +/- 2.5 and 23.2 +/- 3.2 mm (rig ht-RE/left eye-LE), and CT 20.8 +/- 3.2 and 20.9 +/- 2.9 mm (p < 0.000 01, r = 0.72 and 0.65, respectively). MR width on mid-axial scan was 4 .1 +/- 1.6 and 4.2 +/- 1.5 mm (RE/LE). On coronal scans, MR was the mu scle more often enlarged followed by superior, inferior and lateral re ctus. CONCLUSIONS: Exophthalmos measured by HE was greater than by CT- measured one, but with a good correlation. Muscle were not equally aff ected, being MR the most frequently enlarged. MR-width was not related to duration and severity of disease.