FIGURE 4. Transverse ^99mTc-TRODAT-1 SPECT images (A) and discordant ¹⁸F-FDOPA PET images (B) of patient with HYS II PD (patient 15). PET images correlated better with clinical staging than did corresponding ^99mTc-TRODAT-1 SPECT images, which appeared to overestimate disease severity.