The Study Of Radiation Dose In C-arm CT Neurological Intervention Surgery

At present, with the development of clinical medicine and technology, interventional radiology has been widely used in the treatment of diseases. And the awareness of people about the interventional treatment is increasing. At the same time, along with the extensive application of science and technology in the medical treatment, the function of interventional radiology equipment is becoming more and more advanced, interventional radiology equipment types are increasing. And the scope of application is also increasingly integrated and comprehensive.With the development of interventional radiology imaging technology, C-arm CT as a newborn image forming equipment emerged. Since 2004, C-arm CT was applied in clinical interventional radiology and has been widely accepted and applied. C-arm CT also called CBCT or Xper or Dyna CT or Innova CT. It is a new medical imaging device. It is a combination of angiography system and CT. The C-arm CT has a similar function of CT. It can not only access the sectional image information of surgical site, but also can learn about the three-dimensional structure of lesions by 3D reconstruction. Therefore the surgeon can get more abundant image information, make diagnosis and treatment more accurate, so as to improve the interventional therapeutic effect and reduce the occurrence of serious complications.Nowadays, the application of C-arm CT in the treatment of clinical diseases has been reported numerously. But there is few about C-arm CT radiation dose study. Also the research content is not comprehensive and can’t meet the operating persons’ and patients’ requirements of reducing radiation dose during interventional treatments. And the C-arm CT performance tests are not in support of the relevant international and national standards. ObjectiveThe study is to measuring the radiation dose of C-arm CT in a single rotation operation in neurological intervention surgery, and to compare it with 3D-DSA. And to put forward some guiding opinions to reduce the radiation dose for staffs in intervention processes. According to relevant national standards and norms to test the performance of C-arm CT. To provide references to the formulation of C-arm CT standards. MethodsAccording to the national standard of the performance of X ray detection machine, like ’Specifications for quality assurance test for computed tomography X-ray scanners(GB 17589-2011)’ and ’Specifications for testing of image quality control in medical Xray diagnostic equipment(WS76-2011)’ and ’Requirements for radiological protection in medical X-ray diagnosis(GBZ 130-2013)’,to find out the test items applying to Carm CT. Using Magic Max radiation dose dosimeter, X-ray output evaluation system(CT), line card of high contrast resolution, low contrast resolution detecting model, CT performance testing model and CT head phantom to test the performance of C-arm CT. Using the human body phantom which was already placed some TLDs in the internal to measure radiation dose of C-arm CT and 3D-DSA. The irradiation conditions of reference to clinical data and literature. Using the software SPSS 22.0, Origin Pro 8.0, Graph Pad Prism 5 to make data analysis and maps. ResultsThe detection results of the C-arm CT performance to meet the requirements. In a single scan process of C-arm CT in the head, the maximum absorption dose are the lens. It can be 11.755 m Gy.The next is the brain, and it was 9.591 m Gy. The absorption dose of thyroid was 1.003 m Gy. And the minimum absorption dose tissues are uterus, bladder and ovary for 0.001 m Gy.The absorbed dose of the skin and spinal bone marrow image greatly by the distance factor. The biggest change in skin value reached 34.577 m Gy and 2110%. And the next was spinal cord. It was 3.596 m Gy and 699%.With the distance increase, the absorbed dose of the organs were reduced to below 0.270 m Gy. In the results of the head of a single rotation C-arm CT and induced by 3D-DSA irradiation with average absorbed dose, the absorption dose of C-arm CT generally slightly more than 3D-DSA. But the difference was not statistically significant. The head of a single rotation of C-arm CT and 3D-DSA induced by irradiation with effective dose were 0.2358 m Sv and 0.1449 m Sv.Also the difference was not statistically significant. In the results of radiation dose in the medical staff, the difference of C-arm CT and 3D-DSA was not statistically significant. In the case of the use of radiation protective equipment, the equivalent dose of lens of the main operator was 0.331 m Sv.It is 165 times greater than the condition of radiation protection equipment. ConclusionsIn a single time head rotary scanning process, the radiation dose of C-arm CT and 3D-DSA had no obvious difference. Radiation protection products can effectively reduce the absorbed dose of the interventional radiology operations personnel. The results of C-arm CT performance meet the national standards.