الملخص
In recent years, digital radiography (DR) system is widely used in China, and digital X-ray radiography is one of the most common examinations for bone and joint. Optimizing the osteoarthrographic technique, standardizing osteoarthrogram, and summarizing the requirements for radiation protection, will further enhance the clinical application value of digital X-ray imaging in bone and joint examination. Referring to domestic and foreign literatures, and combining the clinical situation of Guangdong-Hong Kong-Macao Greater Bay Area, the experts recruited by the Guangdong-Hong Kong-Macao Greater Bay Area Imaging Technology Alliance reach a consensus on the technique and protection specifications for bone and joint examination to guide and standardize the work related to X-ray examination of bone and joint in the medical imaging department of medical institutions at all levels in the Greater Bay Area.
الملخص
Objective:To investigate the feasibility of reducing radiation dose in coronary CT angiography for patients with arrhythmia with absolute phase and narrow window in prospective electrocardiogram-gating.Methods:200 patients with arrhythmia underwent coronary CT angiography procedure with prospective electrocardiogram-gating adaptive sequence in dual source CT were randomly divided into 2 groups according to the scan mode. Group A was scanned with absolute phase and narrow window(250-450 ms) and group B uesd relative phase and wide window (30%-75%). The other parameters and injection protocol of contrast media were the same in 2 groups. Both image quality and radiation dose of the 2 groups were analyzed.Results:No significant difference of image quality was found between the 2 groups. CTDI vol, DLP, E of group A were all lower than those in group B [CTDI vol : (16.71±8.35) vs.(29.35±17.90)mGy , DLP: (231.04±114.86) vs.(398.27±238.40)mGy·cm , E: (3.23±1.60) vs.(5.57±3.33)mSv, t=-6.40, -6.32、-6.32, P<0.05] . The patients with repeat scan cycles in group A and group B were 81 vs. 22 for 0 cycle , 17 vs. 62 for 1 cycle, 2 vs. 10 for 2 cycles, 0 vs. 6 for 3 cycles( χ2=70.76, P<0.05). Conclusions:The prospective electrocardiogram-gating adaptive CCTA sequence with absolute phase and narrow window can reduce radiation dose while the image quality meets the requirementsfor patients with arrhythmia.