2015年 · 第35卷第12期

Nasopharyngeal carcinoma is one of the common malignant tumors in China. Intensity modulated radiotherapy (IMRT) for nasopharyngeal carcinoma has obvious dosimetric advantages, which can not only improve the quality of life of patients, but also improve the efficacy of radiotherapy^[1,2]。 However, static intensity modulated radiotherapy for nasopharyngeal carcinoma has a large number of irradiation subfields and a long treatment time; Studies have shown that prolonged irradiation time will significantly reduce the biological effects of tumors when the total irradiation dose is the same^[3,4]。 In this study, direct machine parameter optimization (DMPO) method was adopted to reduce the number of irradiation subfields and irradiation time of nasopharyngeal carcinoma IMRT as much as possible, which provided a basis for clinical application on the premise of ensuring that the dose distribution of the target area meets the needs of clinical treatment.

With the release of Part 5 of Reference Person for Radiation Protection, the series of standards of Reference Person for Radiation Protection have now been released and implemented. For the correct understanding and use of this standard, the following interpretation is made.

interventional radiology (interventional radiology) has the characteristics of less trauma, less complications and high accuracy. It has become the three major technologies of modern medicine alongside internal medicine and surgery^[1]。 However, in interventional radiation operation, the exposure of professionals mainly comes from the scattered rays of patients, and a small part comes from the leaked rays or main rays of X-ray tubes. The personnel engaged in interventional radiation procedures are mainly clinicians. According to the investigation, some operators often fail to use protective facilities and wear protective equipment reasonably during interventional radiation procedures, resulting in higher dose irradiation of the whole body, especially the ocular lens. In the distribution of occupational radiation disease diagnosed cases in China, radiation cataract has been ranked second for a long time, accounting for 23.4%^[2]。 There are also many international reports on lens opacity and cataract in interventional professionals^[3]。 Therefore, the estimation of ocular lens exposure dose in the interventional radiology procedure has become a hot topic at home and abroad. Based on the introduction of international standards on the dose limit of ocular lens, this paper discusses the problem of dose estimation of ocular lens for interventional operators.