Because of the unobvious early symptoms and low 5-year survival rate, the early diagnosis and treatment is of great significance for patients with non-small cell lung cancer. Glucose transporter-1 is the most widely distributed glucose transporters in various tissue cells in the human body, whose expression in non-small cell lung cancer is closely related to the histological types, lymph node metastasis, degree of differentiation, progression and prognosis.18F-FDG PET/CT imaging, a molecular imaging diagnostic method, is based on the characteristics of glucose metabolism in malignant tumors, which has been widely applied in the cancer diagnosis, stage division, evaluation of therapeutic effects and prognosis evaluation. Glucose transporter-1 is regulated and influenced by many factors, and it is closely related to 18F-FDG PET/CT imaging. This article briefly reviews the progress in the clinical application and correlation between glucose transporter-1 and 18F-FDG PET/CT imaging for non-small cell lung cancer, in order to improve the diagnosis and treatment of lung cancer.
2-［18F］-fluoro-2-deoxy-D-glucose positron emission tomography/computed tomography (18F-FDG PET/CT) combining positron emission tomography with computed tomography is used to evaluate the body's glucose metabolic changes under different conditions. In addition to its established role in oncological imaging, 18F-FDG PET/CT has clinical utility in suspected inflammation and infection. The technique can identify the source of infection in a timely fashion ahead of morphological changes, map the extent and severity of inflammation, guide the site for tissue biopsy and assess therapy response. This article reviewed the use of 18F-FDG PET/CT in infection and inflammation, such as fever of unknown origin, sarcoidosis, vessel vasculitis, osteomyelitis, joint prosthesis or implant-related complications, human immunodeficiency virus-related infections, and other indications, such as inflammatory bowel disease, so as to provide reference for clinicians to select 18F-FDG PET/CT to help them in the diagnosis and treatment of inflammatory diseases.
Coronary microcirculation dysfunction (CMVD) is an important risk factor for the prognosis of re-perfused ischemic heart. Recent studies showed that the evaluation of CMVD has significant impact on both the early diagnosis of heart diseases relevant to blood supply and prognosis after myocardial reperfusion. In this review, the definition of CMVD from the perspective of pathophysiology was clarified, the principles and features of the state-of-the-art imaging technologies for CMVD assessment were reviewed from the perspective of engineering and the further research direction was promoted.
There are various examination methods for cardiovascular diseases. Non-invasive diagnosis and prognostic information acquisition are the current research hotspots of related imaging examinations. Positron emission tomography (PET)/magnetic resonance imaging (MRI) is a new advanced fusion imaging technology that combines the molecular imaging of PET with the soft tissue contrast function of MRI to achieve their complementary advantages. This article briefly introduces several major aspects of cardiac PET/MRI in the diagnosis of cardiovascular disease, including atherosclerosis, ischemic cardiomyopathy, nodular heart disease, and myocardial amyloidosis, in order to promote cardiac PET/MRI to be more widely used in precision medicine in this field.
Medical whole-body positron emission tomography (PET), one of the most successful molecular imaging technologies, has been widely used in the fields of cancer diagnosis, cardiovascular disease diagnosis and cranial nerve study. But, on the other hand, the sensitivity, spatial resolution and signal-noise-ratio of the commercial medical whole-body PET systems still have some shortcomings and a great room for improvement. The sensitivity, spatial resolution and signal-noise-ratio of PET system are largely affected by the performances of the scintillators and the photo detectors. The design of a PET system is usually a trade-off in cost and performance. A better image quality can be achieved by optimizing and balancing the key components which affect the system performance the most without dramatically increases in cost. With the development of the scintillator, photo-detector and high speed electronic system, the performance of medical whole-body PET system would be dramatically improved. In this paper, we report current progresses and discuss future directions of the developments of technologies in medical whole-body PET system.
ObjectiveTo investigate the imaging characteristics of gallium-68 labeled fibroblast activation protein inhibitor (68Ga-FAPI)-positron emission tomography/magnetic resonance (PET/MR) imaging in patients with liver fibrosis or liver tumor. MethodsThirteen patients with suspected liver tumor who underwent 68Ga-FAPI-PET/MR examination from May 2020 to April 2021 were retrospectively analyzed. Maximum standard uptake value (SUVmax) was investigated. All patients underwent liver surgery or biopsy. Scheuer scoring system was used to evaluate the liver fibrosis. The imaging characteristics of liver fibrosis or liver tumor were analyzed. ResultsThe liver fibrosis was confirmed in 6 patients, including 1 case of S2, 2 cases of S3, and 3 cases of S4. Among them, 4 patients had increased uptake of 68Ga-FAPI, with patchy or diffuse abnormal concentration of liver, and the SUVmax was 7.9±3.1. The liver imaging of the other 2 patients with liver fibrosis showed no obvious radioactive concentration. In addition, 2 patients were diagnosed with hepatocellular carcinoma, its SUVmax was 7.2 and 6.1; 1 patient was diagnosed with hepatobiliary duct carcinoma and its SUVmax was 13.8. Moreover, increased uptake of 68Ga-FAPI was observed in 4 patients with metastatic liver cancer, with SUVmax of 6.7±2.7. ConclusionBoth liver fibrosis and liver tumor are suitable for 68Ga-FAPI-PET/MR examination, which have different imaging characteristics.
The convolutional neural network (CNN) could be used on computer-aided diagnosis of lung tumor with positron emission tomography (PET)/computed tomography (CT), which can provide accurate quantitative analysis to compensate for visual inertia and defects in gray-scale sensitivity, and help doctors diagnose accurately. Firstly, parameter migration method is used to build three CNNs (CT-CNN, PET-CNN, and PET/CT-CNN) for lung tumor recognition in CT, PET, and PET/CT image, respectively. Then, we aimed at CT-CNN to obtain the appropriate model parameters for CNN training through analysis the influence of model parameters such as epochs, batchsize and image scale on recognition rate and training time. Finally, three single CNNs are used to construct ensemble CNN, and then lung tumor PET/CT recognition was completed through relative majority vote method and the performance between ensemble CNN and single CNN was compared. The experiment results show that the ensemble CNN is better than single CNN on computer-aided diagnosis of lung tumor.
Prostate cancer is the most common tumor of the urinary system, and its mortality rate is second only to lung cancer. With the specific and high expression on the surface of prostate cancer cells, prostate-specific membrane antigen (PSMA) has been an ideal theranostic target of prostate cancer with great clinical significance and research value. Positron emission tomography/computed tomography (PET/CT), a new modality of molecular imaging combining functional metabolic information and anatomical structure, provides high diagnostic performance for cancer detection. This paper mainly reviewed recent progress of PSMA inhibitors labeled by positron-emitting radionuclides for early diagnosis, preoperative staging, response assessment, restaging and metastasis detection of prostate cancer.
The aim of this study is to analyze the concordance between EDV, ESV and LVEF values derived from 18F-FDG PET, GSPECT and ECHO in patients with myocardial infarction. Sixty-four patients with coronary artery disease (CAD) and myocardial infarction were enrolled in the study.. Each patient underwent at least two of the above mentioned studies within 2 weeks. LVEF、 EDV and ESV values were analyzed with dedicated software. Statistical evaluation of correlation and agreement was carried out EDV was overestimated by 18F-FDG PET compared with GSPECT [(137.98±61.71) mL and (125.35±59.34) mL]; ESV was overestimated by 18F-FDG PET (85.89±55.21) mL and GSPECT (82.39±55.56) mL compared with ECHO (68.22±41.37) mL; EF was overestimated by 18F-FDG PET (41.96%±15.08%) and ECHO (52.18%±13.87%) compared with GSPECT (39.75%±15.64%), and EF was also overestimated by 18F-FDG PET compared with GSPECT. The results of linear regression analysis showed good correlation between EDV, ESV and LVEF values derived from 18F-FDG PET, GSPECT and ECHO (r=0.643-0.873, P=0.000). Bland-Altman analysis indicated that 18F-FDG PET correlated well with ECHO in the Left ventricular function parameters. While GSPECT correlated well with 18F-FDG PET in ESV, GSPECT had good correlation with Echo in respect of EDV and EF; whereas GSPECT had poor correlation with PET/ECHO in the remaining left ventricular function parameters. Therefore, the clinical physicians should decide whether they would use the method according to the patients' situation and diagnostic requirements.