PET

Primary Sjögren's syndrome (pSS) is a chronic autoimmune exocrinopathy characterized by lymphocytic infiltration, progressive destruction of salivary gland acini, and varying degrees of functional impairment and fibrosis. Conventional imaging provides limited ability to simultaneously evaluate glandular function and inflammatory activity, leading to challenges in disease staging and treatment decision-making. This study explores a conceptual dual-tracer imaging framework using PSMA PET and FAPI PET to delineate complementary biological processes in pSS.

The project's objective is to recruit patients with clinically confirmed or suspected small cell lung cancer, breast cancer, nasopharyngeal carcinoma and other tumours for 68Ga-FL-031 PET imaging and 18F-FDG PET imaging. The histopathology of biopsy or surgical specimens was taken as the final diagnostic criteria, and the presence or absence of tumour lesions was confirmed by the aforementioned imaging. The location and nature of the lesion, and the presence or absence of metastasis, were then judged. The objective was to analyse and clarify the diagnostic efficacy of 68Ga-FL-031 PET imaging for the aforementioned malignant tumours. The objective of this study is to analyse the correlation between the 68Ga-FL-031 PET imaging tumour tissue uptake value and the tumour tissue immunohistochemical staining SSTR2 target expression.

Ischaemic stroke is usually due to occlusion of a cerebral artery by thrombus. However, it is often difficult to identify the source of thrombus, or to confirm thrombus as a cause of ischaemic stroke. Moreover, it is debated whether thrombosis plays any role in certain types of stroke such as lacunar stroke. In preliminary studies, the investigators have evaluated a novel clinical grade thrombus-specific radiotracer, 18F-GP1, which has a high specificity for the glycoprotein IIb/IIIa receptor on activated platelets. The investigations have demonstrated that 18F-GP1 is highly sensitive to in vivo thrombus formation and demonstrates avid binding to thrombus associated with myocardial infarction, pulmonary embolism and aortic bioprosthesis. This study will use this imaging approach to define the role and origin of thrombus in patients with ischaemic stroke, cryptogenic stroke and lacunar stroke.The investigators will also assess its added clinical value in assessing patients with ischaemic stroke.

Chronic pain is a major public health issue, which seriously affects patients' quality of life. Neuroinflammation is an important mechanism resulting in chronic pain. Translocator protein (TSPO) has served as a marker of microglial activation and neuroinflammation. 18F-DPA714, a tracer targeted TSPO, can be used to evaluate the microglial activation and neuroinflammation in vivo by PET imaging.Recent and increasing studies have found changes in TSPO and its ligands in various chronic pain models. Reversing their expressions has been shown to alleviate chronic pain in these models, illustrating the effects of TSPO and its ligands.The investigators aim to explore the clinical feasibility used 18F-DPA714 PET imaging to monitor microglial cells activation of center nervous system in chronic pain patients. This study might reveal significant neuroinflammatory process in the center nervous system of the chronic pain patients. The results of this study might provide a new biomarker of disease pathological progression and indicates that TSPO-based therapy may become an alternative strategy for treating chronic pain.