Clinical presentation: A 21-year-old woman requested a second opinion. She has been treated for Graves' hyperthyroidism for three years. The hyperthyroidism relapsed two times. She suffered from mild exophthalmos and occasionally diplopia. Actually, she had no complaints. 

Palpation: The thyroids were enlarged. There were no palpable nodules.

Result of blood test: subclinical hyperthyroidism on daily 15 mg methimazole therapy (TSH 0.001 mIU/L, FT4 12.9 pM/L, FT3 4.11 pM/L).

Ultrasonography. The thyroids were echonormal and contained hypoechogenic discrete areas none of them corresponded to a nodule. The echogenicity index was around 30%. The vascularization was average.

Surgery was advised.

Total thyroidectomy was performed. Histopathology disclosed diffuse goiter, focal lymphocytic thyroiditis.