title: Parallax error in pinhole thyroid scintigraphy: a critical consideration in the evaluation of substernal goiters.
abstract: Parallax error is found to be another pitfall in pinhole thyroid scintigraphy, i.e., a substernal goiter may appear between the thyroid cartilage marker and the suprasternal notch marker. Unless one is aware of this pitfall, a substernal extension of the thyroid may not be realized or be seriously underestimated in its size and extent. We illustrated the parallax error using a thyroid phantom. An illustrative case is shown.
mesh_terms: D003951:Diagnostic Errors; D005260:Female; D006045:Goiter, Substernal / Q000000981:diagnostic imaging*; D006801:Humans; D008875:Middle Aged; D008961:Models, Structural; D011877:Radionuclide Imaging; D013961:Thyroid Gland / Q000000981:diagnostic imaging*