FIGURE 4.

Clinical scan delineated by expert (reference) and by AI, along with AI-to-expert agreement (DSC, 0.92). Shown are axial images of 50-y-old man with HNC of rhinopharynx. ¹⁸F-FDG PET/CT with intravenous contrast agent showed greatly increased activity corresponding to large tumor process in right rhinopharynx, crossing midline and growing frontally into cavum nasi on right, intracranially on right, medially in fossa media, and along dura laterally. In addition, multiple lymph nodes in neck had greatly increased activity bilaterally. AI correctly avoided including physiologically active areas such as saliva, metal artifact–induced activity, nose tip, brain, and optic nerve. HU = Hounsfield units.