Invalidity of SUV Measurements of Lesions in Close Proximity to Hot Sources due to “Shine-Through” Effect on FDG PET-CT Interpretation

<table>Transaxial FDG PET-CT images of the neck show a large lesion with <svg height="15.65" id="M16" style="vertical-align:-3.3907pt" version="1.1" viewbox="0 0 57.512501 15.65" width="57.512501" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink">
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</svg> 25 in the right lobe of the thyroid (arrow A). There is a 1.5 cm nodule with mild to moderate uptake in the left lobe, but unexpectedly measured <svg height="15.65" id="M17" style="vertical-align:-3.3907pt" version="1.1" viewbox="0 0 57.512501 15.65" width="57.512501" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink">
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</svg> is 18 (arrow B).</table>

Radiology Research and Practice

fig3

Figure 3

Figure 3: Invalidity of SUV Measurements of Lesions in Close Proximity to Hot Sources due to “Shine-Through” Effect on FDG PET-CT Interpretation 