Radionuclide Imaging of the Gut–Brain Axis in Parkinson Disease

(Top) Representative ¹¹C-donepezil SUV images of healthy control subject (HC), subject with isolated REM sleep behavior disorder (iRBD), brain-first PD patient (BrPD), body-first PD patient (BoPD), and vagotomized patient (Vago). Signal is high in HC and BrPD. Images are scaled from 0 to 3 SUV. Plot shows medians and interquartile ranges for ¹¹C-donepezil data. (Bottom left) CT images of normal and increased number of retained radiopaque markers (ROMs) (i.e., normal and increased colon transit time). Plot shows medians and interquartile ranges for ROM data. (Bottom right) CT images of normal and increased colon volume. Plot shows medians and interquartile ranges for colon volume data.