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.
Objective To summary the recent progression of imaging methods which mainly applied on the early detection and qualitative diagnosis of pancreatic cancer. Method The newest related literatures between home and abroad were collected and reviewed. Results Ultrasonic, computed tomography, magnetic resonance imaging and positron emission tomography mostly be used on pancreatic cancer detection and diagnosis. Conclusion Each method gets its own advantage even computed tomography seems like dominated on the detection and diagnosis pancreatic cancer, moreover, magnetic resonance imaging has been improved rapidly in recent years which shows its enormous potential.
Primary hepatocellular carcinoma is a common cancer. Many patients are found with intermediate-advanced stage, rapid development, poor treatment and high mortality. 18F-fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG PET/CT) can discover the early lesions and therefore plays an important role in diagnosis, treatment and prognosis of patients with hepatocellular carcinoma. It especially has obvious advantages in detecting metastasis and monitoring recurrence. However, 18F-FDG PET/CT imaging has poor quality and low diagnosis rate. Understanding the advantages and limitations of 18F-FDG PET/CT can provide better basis for clinical diagnosis and treatment for hepatocellular carcinoma patients. This article briefly introduces the research and application of 18F-FDG PET/CT in the diagnosis and treatment of hepatocellular carcinoma.
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.
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.
The widespread use of low-dose computed tomography (LDCT) in lung cancer screening has enabled more and more lung nodules to get identified of which more than 20% are multiple pulmonary nodules. At present, there is no guideline or consensus for multiple pulmonary nodules whose management is based primarily on the pulmonary imaging characteristics and associated risk factors. Herein, this review covers the imaging methods, CT appearances and management of multiple pulmonary nodules.
Objective To investigate the accuracy of 18F-FDG positron emission tomography/computed tomography (PET/CT) combined with CT three-dimensional reconstruction (CT-3D) in the differential diagnosis of benign and malignant pulmonary nodules. Methods The clinical data of patients who underwent pulmonary nodule surgery in the Department of Thoracic Surgery, Northern Jiangsu People's Hospital from July 2020 to August 2021 were retrospectively analyzed. The preoperative 18F-FDG PET/CT and chest enhanced CT-3D and other imaging data were extracted. The parameters with diagnostic significance were screened by the area under the receiver operating characteristic (ROC) curve (AUC). Three prediction models, including PET/CT prediction model (MOD PET), CT-3D prediction model (MOD CT-3D), and PET/CT combined CT-3D prediction model (MOD combination), were established through binary logistic regression, and the diagnostic performance of the models were validated by ROC curve. Results A total of 125 patients were enrolled, including 57 males and 68 females, with an average age of 61.16±8.57 years. There were 46 patients with benign nodules, and 79 patients with malignant nodules. A total of 2 PET/CT parameters and 5 CT-3D parameters were extracted. Two PET/CT parameters, SUVmax≥1.5 (AUC=0.688) and abnormal uptake of hilar/mediastinal lymph node metabolism (AUC=0.671), were included in the regression model. Among the CT-3D parameters, CT value histogram peaks (AUC=0.694) and CT-3D morphology (AUC=0.652) were included in the regression model. Finally, the AUC of the MOD PET was verified to be 0.738 [95%CI (0.651, 0.824)], the sensitivity was 74.7%, and the specificity was 60.9%; the AUC of the MOD CT-3D was 0.762 [95%CI (0.677, 0.848)], the sensitivity was 51.9%, and the specificity was 87.0%; the AUC of the MOD combination was 0.857 [95%CI (0.789, 0.925)], the sensitivity was 77.2%, the specificity was 82.6%, and the differences were statistically significant (P<0.001). Conclusion 18F-FDG PET/CT combined with CT-3D can improve the diagnostic performance of pulmonary nodules, and its specificity and sensitivity are better than those of single imaging diagnosis method. The combined prediction model is of great significance for the selection of surgical timing and surgical methods for pulmonary nodules, and provides a theoretical basis for the application of artificial intelligence in the pulmonary nodule diagnosis.
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.
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.