Uniformity measurement of newly installed camera heads of positron-emitting tracer imaging system

Kawachi, Naoki; Suzui, Nobuo; Ishii, Satomi; Yamazaki, Haruaki; Fujimaki, Shu

We have performed phantom experiments for the quarterly maintenance of the uniformity and sensitivity correction of the PETIS to assess the performance of its newly installed detector head and maintain a sufficiently high image quality for plant study. In order to quantitatively acquire the analyzable dynamic data of PETIS images, it is mandatory to begin a scheduled work for constant quality control. We prepared a flat uniform phantom containing a radioactive solution of Na-22. Newly installed PETIS No. 4 acquired for 5 min to image the phantom in this maintenance experiment. All images were corrected for detector geometry and counting rate losses. To analyze the image quality of the phantom data, we estimated the mean value, standard deviation, and the root mean square uncertainty of a selected region of interest in the images. These works on the maintenance of PETIS quality control ensure quantitative kinetic analysis and support many other plant physiological experiments of PETIS studies.