Figure 1. (a) On the gadolinium-diethyltriaminepentaacetic acid (Gd-DTPA)-enhanced T₁ weighted MR image before treatment, a relatively low-intensity area with peripheral enhancement is seen in the left side of the tongue. (b) Positron emission tomography (PET)–CT obtained 7 years and 3 months after treatment shows a high uptake area in the left side of the tongue. (c) Gd-DTPA-enhanced T₁ weighted MR image obtained 3 weeks after the PET examination shows a slight increase in signal intensity in the left side of the tongue. (d) A T₂ weighted MR image at the same time showed a decrease in signal intensity, indicating a fibrotic change.