[Thyroid ophthalmopathy: clinical and tomographic study].

BACKGROUND

To evaluate exophthalmos by Hertel exophthalmometer (HE) compared to computed tomography (CT), and extraocular muscle width on CT 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 ophthalmopathy (Graves' disease, n = 57; Hashimoto's thyroiditis, n = 2). Muscle 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 (right-RE/left eye-LE), and CT 20.8 +/- 3.2 and 20.9 +/- 2.9 mm (p < 0.00001, 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 muscle more often enlarged followed by superior, inferior and lateral rectus.

CONCLUSIONS

Exophthalmos measured by HE was greater than by CT-measured one, but with a good correlation. Muscle were not equally affected, being MR the most frequently enlarged. MR-width was not related to duration and severity of disease.