The diagnosis of extrapulmonary tuberculosis (EPTB): scanning protocols and innovative methods for image quality improvement of FDG PET/CT imaging

摘要

Fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT) scan offers synergistic clinical advantages during the initial staging, re-staging and therapeutic response assessment of a wide variety of cancers, as compared to other conventional imaging modalities. In addition, the use of FDG PET/CT imaging has expanded into the diagnostic evaluation and treatment follow-up of the infectious disease of tuberculosis (TB). However, there is still a lack of evidence concerning the application of this hybrid imaging in the detection of extrapulmonary tuberculosis (EPTB) lesions. Therefore, the major aim of this research is to determine the feasibility of FDG PET/CT imaging for detecting EPTB lesions. A clinical study was retrospectively and prospectively conducted on a series of patients who were either highly suspected or confirmed with EPTB infectious disease. The results show that FDG PET/CT is a reliable and practical imaging modality for detecting EPTB lesions. However, the utilisation of dual time point imaging (DTPI) of FDG PET/CT scan is not a useful imaging technique in distinguishing between EPTB and non-EPTB lesions. On the contrary, the findings of clinical and phantom studies have discovered that non-ionic iodine-based contrast media can be safely applied during the CT scan of FDG PET/CT imaging, without affecting its diagnostic accuracy. Furthermore, based on the calculations, the effective dose arising from FDG PET/CT scan is still considerably low even if the additional delayed CT scan has been performed. In conclusion, these research works provide the beginnings of a suitable body of evidence upon which a clinician can make a diagnostic decision on whether use of FDG PET/CT scan is indicated for the detection of EPTB lesions.