Clinical data: A 69-year-old woman came to routine follow-up. She was operated on and got radioiodine therapy 13 years ago because of a T1a papillary cancer.

Palpation: no abnormality.

Laboratory tests: TSH 0.71, thyroglobulin< 0.1 ng/mL, anti-hTg < 0,9 U/mL.

Ultrasonography. There was no thyroid tissue in the thyroid beds. The transverse view of the left lobe was deceptive because the muscle fiber on this scan mimicked thyroid remnant. Longitudinal section was decisive.

Comment. As in many cases, the longitudinal scan is more informative than the transverse view regarding the judgement of a discrete mass.