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Objective To determine the real time radiation dose rate displayed on DSA equipment in interventional management for patients with coronary heart disease in order to provide medical staff with useful basis to reasonably control the radiation dose. Methods A total of 30 patients with coronary heart disease, who received interventional treatment at authors’ hospital in September 2014 with a GE DSA unit, were randomly selected. Intraoperative radiation dose rates when fluoroscopy was converted to movies , which were displayed on DSA at respective sequence, were determined, and the results were analyzed and compared. Results The fluoroscopy radiation dose rate ranged from 18.5 to 212.0 mGy/min, the mean value was (114.7±42.1) mGy/min;while the radiation dose rate of movies varied from 216 to 1 691 mGy/min, with a mean value of(970.1±298.4) mGy/min. The overall mean fluoroscopy-to-movies radiation dose ratio was 1 ∶8.5. The larger the digital flat panel detector area was , the bigger the mean radiation dose rate would be and the more obvious increase in the mean radiation dose rate of movies than that of the fluoroscopy would be observed; the mean radiation dose rate of fluoroscopy was lower than that of movies , and the difference was significantly. Conclusion During the performance of coronary intervention , the medical staff should make reasonable choice of the equipment and closely observe the dynamic real-time display of the radiation dose rate, promptly adjust the inspection mode and the controllable parameters when it is needed , make immediate evaluation of dose level that might cause radiation injury to the patient , and reasonably control the radiation dose to reduce the effects of ionizing radiation on human health.
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Objective To evaluate the methods and the factors of affecting imaging quality of 3D CE MRA of carotid arteries.Methods 3D CE MRA in 48 patients were performed using 1.5T super conductive MR scanner,cervical and lumbar combination phased array coils. All patients were examined using intravenous injection Gd-DTPA and breath-hold 3D FLASH sequence. Results Imaging quality was satisfied in 46/48 patients (96%). MIP and MPR could clearly showed normal anatomy. The site,size and stenosis degree of the lesion were also demonstrated. Compared to surgery,DSA and/or ultrasound results , in 23 patients, the sensitivity and specificity of 3D CE MRA were 100% and 100% respeectively for the lesion of carotid arteries. Conclusion High quality images of 3D CE MRA mainly depends on determining the best acquisition delay time,optimizing injection volume and rate of contrast material,using reasonable sequence parameters and skilled level of operators.
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Objective To study the method and skill of CT angiography of inferior vena cava.Methods CTA of inferior vena cava was performed with PECK ER 6000 spiral CT,using 3.0～4.0 mm slice thickness at pitch 1.25～1.5, and 1.5 ～2.0 mm reconstruction interval by using smooth function in 12 cases.Results CTA images were acquired satisfactory in all cases. The normal dissection structure of inferior vena cava,the location,extent and degree of obstruction of inferior vena cava after setting up on VOXEL stat ion. To compare with DSA and/or operation the accuracy was 91.67% in showi ng the lesions by CTA.Conclusion High quality imaging of inferior vena cava by CTA is depended on the accuracy of scanning opportunity after injection of contr ast material and the suitability of scanning parameter, precise scan method and the skill of operator.