利用体重指数分类的数字X线摄影中的患者剂量

PATIENT DOSE IN DIGITAL RADIOGRAPHY UTILISING BMI CLASSIFICATION.

作者信息

Metaxas Vasileios I, Messaris Gerasimos A, Lekatou Aristea N, Petsas Theodore G, Panayiotakis George S

机构信息

Department of Medical Physics, School of Medicine, University of Patras, Patras, Greece.

Department of Radiology, School of Medicine, University of Patras, Patras, Greece.

出版信息

Radiat Prot Dosimetry. 2019 Aug 1;184(2):155-167. doi: 10.1093/rpd/ncy194.

DOI:10.1093/rpd/ncy194

PMID:30452729

Abstract

Dose audit is important towards optimisation of patients' radiation protection in diagnostic radiography. In this study, the effect of the body mass index (BMI) on radiation dose received by 1869 adult patients undergoing chest, abdomen, lumbar spine, kidneys and urinary bladder (KUB) and pelvis radiography in an X-ray room with a digital radiography system was investigated. Patients were categorised into three groups (normal, overweight and obese) based on the BMI values. The patients' entrance surface air kerma (ESAK) and the effective dose (ED) were calculated based on the X-ray tube output, exposure parameters and technical data, as well as utilising appropriate conversion coefficients of the recorded kerma area product (KAP) values. The local diagnostic reference levels (LDRLs) were established at the 75th percentile of the distribution of ESAK and KAP values. Statistically, a significant increase was found in ESAK, KAP and ED values, for all examinations, both for overweight and obese patients compared to normal patients (Mann-Whitney test, p < 0.0001). Regarding the gender of the patients, a statistically significant increase was found in the dose values for male patients compared to female patients, except for the chest LAT examinations (Mann-Whitney test, p = 0.06). The percentage increase for chest PA, chest LAT, abdomen AP, lumbar spine AP, lumbar spine LAT, pelvis AP and KUB AP in overweight patients was 75%, 100%, 136%, 130%, 70%, 66% and 174% for median ESAK, 67%, 81%, 135%, 134%, 85%, 63% and 172% for median KAP, as well as 89%, 54%, 146%, 138%, 82%, 57% and 183% for median ED values, respectively. For obese patients, the corresponding increases were 200%, 186%, 459%, 345%, 203%, 150% and 785% for median ESAK, 200%, 185%, 423%, 357%, 227%, 142% and 597% for median KAP, as well as 222%, 156%, 446%, 363%, 218%, 136% and 625% for median ED. The corresponding LDRLs for overweight patients were 0.17 mGy, 1.21 mGy, 3.74 mGy, 7.70 mGy, 7.99 mGy, 4.07mGy, 5.03 mGy and 0.13 Gy cm2, 0.69 Gy cm2, 2.35 Gy cm2, 2.10 Gy cm2, 2.59 Gy cm2, 2.13 Gy cm2, 2.49 Gy cm2 in terms of ESAK and KAP values, respectively, while in the case of obese patients were 0.28 mGy, 1.82 mGy, 7.26 mGy, 15.10 mGy, 13.86 mGy, 6.89 mGy, 13.40 mGy and 0.21 Gy cm2, 1.10 Gy cm2, 4.68 Gy cm2, 4.01 Gy cm2, 4.80 Gy cm2, 3.27 Gy cm2, 6.02 Gy cm2, respectively. It can be concluded that overweight and obese patients received a significantly increased radiation dose. Careful adjustment of imaging protocols is needed for these patients to reduce patient dose, while keeping the image quality at an acceptable level. Additional studies need to be conducted for these patient groups, that could further contribute to the development of radiation protection culture in diagnostic radiography.

摘要

剂量审核对于优化诊断放射学中患者的辐射防护至关重要。在本研究中，调查了体重指数（BMI）对1869名成年患者在配备数字放射成像系统的X射线室中进行胸部、腹部、腰椎、肾脏及膀胱（KUB）和骨盆放射成像时所接受辐射剂量的影响。根据BMI值将患者分为三组（正常、超重和肥胖）。基于X射线管输出、曝光参数和技术数据，并利用记录的比释动能面积乘积（KAP）值的适当转换系数，计算患者的体表空气比释动能（ESAK）和有效剂量（ED）。在ESAK和KAP值分布的第75百分位数处确定当地诊断参考水平（LDRL）。统计学上，与正常患者相比，超重和肥胖患者在所有检查中的ESAK、KAP和ED值均有显著增加（曼-惠特尼检验，p < 0.0001）。关于患者的性别，除胸部侧位检查外，男性患者的剂量值与女性患者相比有统计学显著增加（曼-惠特尼检验，p = 0.06）。超重患者胸部后前位（PA）、胸部侧位（LAT）、腹部前后位（AP）、腰椎前后位（AP）、腰椎侧位（LAT）、骨盆前后位（AP）和KUB前后位的ESAK中位数增加百分比分别为75%、100%、136%、130%、70%、66%和174%，KAP中位数增加百分比分别为67%、81%、135%缉134%、85%、63%和172%，ED中位数增加百分比分别为89%、54%、146%、138%、82%、57%和183%。对于肥胖患者，ESAK中位数相应增加分别为200%、186%、459%、345%、203%、150%和785%，KAP中位数增加分别为200%、185%、423%、357%、227%、142%和597%，ED中位数增加分别为222%、156%、446%、363%、218%、136%和625%。超重患者的相应LDRL在ESAK值方面分别为0.17 mGy、1.21 mGy、3.74 mGy、7.70 mGy、7.99 mGy、4.07 mGy、5.03 mGy，在KAP值方面分别为0.13 Gy cm2、0.69 Gy cm2、2.35 Gy cm2、2.10 Gy cm2、2.59 Gy cm2、2.13 Gy cm2、2.49 Gy cm2，而肥胖患者的相应LDRL分别为缉0.28 mGy、1.82 mGy、7.26 mGy、15.10 mGy、13.缉86 mGy缉6缉89 mGy、13.40 mGy和0.21 Gy cm2、1.10 Gy cm2缉4.68 Gy cm2、4.01 Gy cm2、4.80 Gy cm2、3.27 Gy cm2、6.02 Gy cm2。可以得出结论，超重和肥胖患者接受的辐射剂量显著增加。需要仔细调整这些患者的成像方案，以降低患者剂量，同时将图像质量保持在可接受水平。需要对这些患者群体进行更多研究，这可能会进一步促进诊断放射学中辐射防护文化的发展。