Urairat J, Asavaphatiboon S, Singhara Na Ayuthaya S, Pongnapang N
School of Medical Physics, Faculty of Medicine Ramathibodi Hospital, Mahidol University, Bangkok, Thailand.
Biomed Imaging Interv J. 2011 Jul-Sep;7(3):e22. doi: 10.2349/biij.7.3.e22. Epub 2011 Jul 1.
This study was carried out to assess the radiation dose to patients undergoing interventional radiology procedures at Ramathibodi Hospital, Bangkok, Thailand.
Data were collected from 60 patients under transarterial oily-chemoembolisation (TOCE) and femoral angiography performed with the Toshiba Infinix model VC-i FPD single plane system. Data were also collected from 60 patients who underwent brain arteriovenous malformations (AVM) and dural-arteriovenous fistula (DAVF) embolisation, performed with the Toshiba Infinix model VF-i bi-plane systems. A built-in air kerma area product (KAP) meter calibrated in situ was used for the skin dose calculation.
The calibration coefficient of air kerma area product meter at tube voltage between 50 kV and 100 kV was found to vary within ± 5.07%, ± 7.2%, ± 4.86 % from calibration coefficient of 80 kV for a single-plane, tube 1 and tube 2 of bi-plane x-ray system, respectively. Mean air kerma area product values were 90.99 ± 52.89, 31.02 ± 17.92, 33.11 ± 23.99 (Frontal), 35.01 ± 19.10 (Lateral), 50.15 ± 44.76 (Frontal), 97.31 ± 44.12 (Lateral) Gy-cm(2) for transarterial oily-chemoembolisation, femoral angiography, diagnostic cerebral angiography, therapeutic cerebral angiography, respectively. The therapeutic cerebral angiography procedure was found to give the highest entrance dose, number of images and fluoroscopy time: 362.63 cGy (Lateral), 1015 images (Lateral) and 126 minutes, respectively. However, the highest air kerma area product value was from transarterial oily-chemoembolisation with 264.37 Gy-cm(2). There were 2 cases of therapeutic cerebral angiography, where the patient entrance dose was higher than 3 Gy in the frontal view, which reached the deterministic threshold for temporary epilation.
Very wide variationswere found in patient dose from different interventional procedures. There is a need for a dose record system to provide feedback to radiologists who perform the procedures; especially in cases where the dose exceeds the deterministic threshold.
本研究旨在评估泰国曼谷拉玛提波迪医院接受介入放射学检查的患者所接受的辐射剂量。
收集了60例行经动脉油性化疗栓塞术（TOCE）和使用东芝Infinix型号VC-i FPD单平面系统进行股动脉血管造影的患者的数据。还收集了60例行脑动静脉畸形（AVM）和硬脑膜动静脉瘘（DAVF）栓塞术、使用东芝Infinix型号VF-i双平面系统的患者的数据。使用在现场校准的内置空气比释动能面积乘积（KAP）仪来计算皮肤剂量。
发现对于单平面X射线系统的管1、双平面X射线系统的管1和管2，在管电压50 kV至100 kV之间时，空气比释动能面积乘积仪的校准系数相对于80 kV的校准系数分别在±5.07%、±7.2%、±4.86%范围内变化。经动脉油性化疗栓塞术、股动脉血管造影、诊断性脑血管造影、治疗性脑血管造影的平均空气比释动能面积乘积值分别为90.99±52.89、31.02±17.92、33.11±23.99（正位）、35.01±19.10（侧位）、50.15±44.76（正位）、97.31±44.12（侧位）Gy·cm²。发现治疗性脑血管造影检查产生的入射剂量、图像数量和透视时间最高，分别为362.63 cGy（侧位）、1015张图像（侧位）和126分钟。然而，空气比释动能面积乘积的最高值来自经动脉油性化疗栓塞术，为264.37 Gy·cm²。有2例治疗性脑血管造影，患者正位视图的入射剂量高于3 Gy，达到了暂时性脱毛的确定性阈值。
不同介入操作的患者剂量存在很大差异。需要一个剂量记录系统，以便向进行操作的放射科医生提供反馈；特别是在剂量超过确定性阈值的情况下。
