320mm CT scannerVGC can cover the wall heart in one rotation,can aid in reducing the degeneration exposure during ECG-gated coronary CT and geography.Decently, we have developed those modulated dynamic CCTA for the detection of functional ischemia.We compare the radiation dose of this method with that of the standard CCTA methodand the latest diagnostic reference levels DRLs.This technique has obtained an international patent under the invention name,functional ischemia detection technique by coronary artery CT4D flow image.Please refer to the last URL for public information.The study included consecutive patients with coronary artery disease who underwent CCTA with a 320mm scanner.A total of 164 patients were finally included.Dynamic CCTA and standard CCTA were performed in 87 and 77 patients respectively.Dynamic CCTA was continuously performed in mid-tier store for 8 to 12 cardiac cycleswith prospective ECG-gating scans after 10 seconds injection contrast medium.One scan was performed as a boost scan for standard CCTA as a peak phase of the ascending order.The slide shows comparison of radiation dose of dynamic and standard CCTA.In comparison between the prep scan and the test scan to determine the timing of CCTA acquisition,CTDIB was significantly lower for the test scan than for the prep scan.CTDIB was significantly lower for dynamic CCTA than for standard CCTA.DLP was significantly lower for dynamic CCTA than for standard CCTA.This is the frequency of radiation dose above the DRLs.For standard scans,CTDIB and DLP exceeded the 2020 DRL for Japan in 60% and 70% of cases respectively.In contrast, rate for the dynamic scan was only 1% for CTDIB and 0% for DLP.The radiation dose of dynamic CCTA does not exceed that of standard CCTA and is sufficient to meet the latest DRL.Dynamic CCTA was able to reduce radiation exposure by 50% of the DLP compared to standard CCTA.For more information on dynamic CCTA, please refer to the following paper.