Head-to-head Comparison of Diagnosis Value of Pulmonary Fibrosis on 68Ga-FAPI-04 and 18F-FDG PET-CT

68Ga-fibroblast activating protein inhibitors(FAPI) has been developed as a tumor-targeting agent as fibroblast activation protein is overexpressed in cancer-associated fibroblasts and some inflammation,such as inflammatory bowel disease. And it might be more sensitive than FDG in detecting a certain type of inflammations according to our preliminary research. Thus this prospective study is going to investigate whether 68Ga-FAPI PET/CT may be superior for diagnosis, therapy response assessment and follow-up of Pulmonary fibrosis than 18F-FDG PET/CT.