CT scans the radiation dose, the country has introduced new standards!

Recently, the National Health Council issued the "X-ray computed tomography adult diagnostic reference level", which is suitable for routine CT scans in adults, but not for adult health checkups, children's CT scan, and various cone beam CT scans. The official implementation time is scheduled for April 1, 2019.

The radiation dose and diagnostic reference level of common CT examination items in adult patients are shown in Table 1.

1. In radiodiagnostic activities, the main objective is to obtain acceptable image quality or sufficient diagnostic information. Use diagnostic reference levels to assist in managing the patient's radiation dose, matching the radiation dose with the purpose of clinical diagnosis, and reducing illicit The frequency of occurrence of high or low doses.

2. According to the different medical imaging tasks, each province and city can formulate the diagnostic reference level of the region according to the medical equipment conditions of the region and the situation of the staff.

3. The diagnostic reference level provides a reasonable dose indication for a moderately sized patient population. It does not apply to dose references for specific body types and does not apply to individual patients.

4. The employer shall perform a dose check of not less than 20 people per year for the common inspection items of each CT equipment.

5. In clinical practice, if the patient's dose often exceeds the corresponding diagnostic reference level, the medical procedure and equipment should be checked to determine if the radiation protection is optimized; otherwise, the necessary diagnostic information should be ensured. At the same time, to minimize the patient's exposure dose. If the patient's dose is generally lower than 25% of the survey data, it is necessary to check whether the CT scan can provide useful diagnostic information and bring the expected medical benefits to the patient. Advanced imaging equipment or reconstruction algorithms can significantly reduce the patient's dose (less than 25% of the survey data), and the image quality can meet the diagnostic needs, then you can continue the medical task, otherwise corrective action should be taken as needed.

6. Units with advanced imaging equipment technology or reconstruction algorithms and high level of radiological staff's business capability can further reduce the radiation dose according to the possible level (50% digits) to optimize the radiation protection of patients.

7. The diagnostic reference level should be periodically revised according to the technical level of the imaging equipment and the change of the radiation protection knowledge level of the operator. It is not a dose limit and cannot be used in the law. Regulation And commercial purposes.

This item standard Beijing Tongren, affiliated to Capital Medical University hospital , Union Hospital of Tongji Medical College, Huazhong University of Science and Technology, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, China disease The Center for Radiation Protection and Nuclear Safety of the Center for Prevention and Control, Beijing Municipal Center for Disease Control and Prevention, etc.