Ultrasound in early thyroid orbitopathy.

Fourteen patients with unilateral exophthalmos were found on A-scan ultrasound examination to have enlarged extraocular muscles. Thyroid dysfunction later was documented in 12 patients (86%) by laboratory tests and subsequent clinical examination. The suspicion of endocrine orbitopathy was based on the presence of enlarged extraocular muscles in both orbits and on the difference in thickness between corresponding muscles. A-scan orbital examination including specific muscle measurements is a simple and apparently reliable method of diagnosing early thyroid orbitopathy.