High incidence of normal thyroid gland volume in patients with Graves' disease.

Thyroid function and thyroid gland volume, ultrasonically determined, were investigated in ninety consecutive untreated patients with Graves' disease. Twenty-eight patients (31%) had no clinically detectable goitre. Median thyroid gland volume was 31 ml (range 12-99 ml). Twenty-one patients (23%) had a normal calculated thyroid volume. Thyroid volume did not correlate with any measure of thyroid function. The lack of a goitre in a large portion of patients with Graves' disease could be responsible for delayed diagnosis and subsequent treatment of these patients.