Prins R, Dauer L T, Colosi D C, Quinn B, Kleiman N J, Bohle G C, Holohan B, Al-Najjar A, Fernandez T, Bonvento M, Faber R D, Ching H, Goren A D
Department of Medical Physics, Memorial Sloan-Kettering Cancer Center, New York, New York, USA.
Oral Surg Oral Med Oral Pathol Oral Radiol Endod. 2011 Oct;112(4):502-7. doi: 10.1016/j.tripleo.2011.04.041. Epub 2011 Jul 28.
In light of the increased recognition of the potential for lens opacification after low-dose radiation exposures, we investigated the effect of leaded eyeglasses worn during dental cone-beam computerized tomography (CBCT) procedures on the radiation absorbed dose to the eye and suggest simple methods to reduce risk of radiation cataract development.
Dose measurements were conducted with the use of 3 anthropomorphic phantoms: male (Alderson radiation therapy phantom), female (CIRS), and juvenile male (CIRS). All exposures were performed on the same dental CBCT machine (Imtec, Ardmore, OK) using 2 different scanning techniques but with identical machine parameters (120 kVp, 3.8 mA, 7.8 s). Scans were performed with and without leaded glasses and repeated 3 times. All measurements were recorded using calibrated thermoluminescent dosimeters and optical luminescent dosimetry.
Leaded glasses worn by adult and pediatric patients during CBCT scans may reduce radiation dose to the lens of the eye by as much as 67% (from 0.135 ± 0.004 mGy to 0.044 ± 0.002 mGy in pediatric patients).
Leaded glasses do not appear to have a deleterious effect on the image quality in the area of clinical significance for dental imaging.
鉴于低剂量辐射暴露后晶状体混浊可能性的认识不断增加,我们研究了牙科锥形束计算机断层扫描(CBCT)过程中佩戴铅眼镜对眼部辐射吸收剂量的影响,并提出降低辐射性白内障发生风险的简单方法。
使用3个仿真人体模型进行剂量测量:男性(Alderson放射治疗模型)、女性(CIRS)和青少年男性(CIRS)。所有扫描均在同一台牙科CBCT机(Imtec,阿德莫尔,俄克拉何马州)上进行,使用2种不同的扫描技术,但机器参数相同(120 kVp,3.8 mA,7.8 s)。扫描分别在佩戴和不佩戴铅眼镜的情况下进行,并重复3次。所有测量均使用校准后的热释光剂量计和光致发光剂量测定法记录。
成人和儿童患者在CBCT扫描过程中佩戴铅眼镜可使眼部晶状体的辐射剂量降低多达67%(儿童患者从0.135±0.004 mGy降至0.044±0.002 mGy)。
对于牙科成像具有临床意义的区域,铅眼镜似乎对图像质量没有有害影响。