Advances in Cardiac Computed Tomography Functional Imaging Technology.

Cardiovascular disease (CVD) is the leading cause of death among patients in China, and cardiac computed tomography (CT) is one of the most commonly used examination methods for CVD. Coronary artery CT angiography can be used for the morphologic evaluation of the coronary artery. At present, cardiac CT functional imaging has become an important direction of development of CT. At present, common CT functional imaging technologies include transluminal attenuation gradient, stress dynamic CT myocardial perfusion imaging, and CT-fractional flow reserve. These three imaging modes are introduced and analyzed in this review.

Differentiation and diagnosis of benign and malignant testicular lesions using 18F-FDG PET/CT.

OBJECTIVES: The purpose of this study was to evaluate the differential diagnostic value of 18F-fluorodeoxy glucose positron emission tomography/computed tomography (18F-FDG PET/CT) for benign and malignant testicular lesions. METHODS: The PET/CT scans of 53 patients with testicular lesions confirmed by biopsy or surgical pathology were retrospectively analyzed. There were 32 cases of malignant tumors and 21 cases of benign lesions. Differences in the maximum standardized uptake value (SUVmax) measurements and the SUVmax lesion/background ratios between benign and malignant lesions were analyzed. The diagnostic value of this PET/CT modality for the differential diagnosis of benign versus malignant testicular lesions was calculated. RESULTS: The differences in the SUVmax measurements and the SUVmax lesion/background ratios between benign and malignant lesions were statistically significant (SUVmax: Z=-4.295, p=0.000; SUVmax lesion/background ratio: Z=-5.219, p=0.000); specifically, both of these indicators were higher in malignant lesions compared to benign lesions. An SUVmax of 3.75 was the optimal cutoff value to differentiate between benign and malignant testicular lesions. The diagnostic sensitivity, specificity, accuracy, positive predictive value, and negative predictive value of this PET/CT modality in the differential diagnosis of benign versus malignant testicular lesions were 90.6%, 80.9%, 86.8%, 87.9%, and 85.0%, respectively. CONCLUSIONS: 18F-FDG PET/CT can accurately identify benign and malignant testicular lesions.

Preparation methods prior to PET/CT scanning that decrease uptake of 18F-FDG by myocardium, brown adipose tissue, and skeletal muscle.

BACKGROUND: The hypermetabolic environment of the myocardium, brown adipose tissue (BAT), and muscle will have an effect on the diagnostic accuracy of 18F-fluorodeoxyglucose (18F-FDG) positron-emission tomography (PET)/computed tomography (CT). A low carbohydrate, high fat, and protein-permitted diet before PET/CT scanning can reduce the degree of 18F-FDG uptake by the myocardium, brown adipose tissue, and skeletal muscle. PURPOSE: To determine the effect of a low carbohydrate, high fat and protein-permitted diet on 18F-FDG uptake by myocardium, BAT, and muscle during PET/CT. MATERIAL AND METHODS: A total of 126 patients who adhered to two meals before PET/CT scanning (that were prepared using a low carbohydrate, high fat, and protein-permitted diet), i.e. the diet group, were compared with 126 patients who fasted for at least 12 h prior to scanning (i.e. the fasting group). The degree of 18F-FDG uptake within the myocardium, BAT, and muscle were stratified into four grades (range, 0-3) with 0 for negligible uptake, and 3 for intense uptake. Correlations between the diet and fasting groups with respect to degree of 18F-FDG uptake within the myocardium, BAT, and muscle were analyzed. RESULTS: The degree of 18F-FDG uptake within the myocardium, BAT, and muscle in the diet group was significantly lower compared with the 18F-FDG uptake within myocardium, BAT, and muscle in the fasting group (P < 0.001, P = 0.001, P < 0.001). CONCLUSION: A low carbohydrate/high fat diet before 18F-FDG injection can suppress uptake of 18F-FDG within the myocardium, BAT, and skeletal muscle.