Pomeroy Christopher L, Mason J Bohannon, Fehring Thomas K, Masonis John L, Curtin Brian M
OrthoCarolina Hip and Knee Center, Charlotte, North Carolina.
J Arthroplasty. 2016 Aug;31(8):1742-5. doi: 10.1016/j.arth.2016.01.031. Epub 2016 Jan 29.
Utilization of the direct anterior approach (DAA) for total hip arthroplasty (THA) has increased in the last decade with fluoroscopy often used to confirm implant position, leg length, and offset. Radiation exposure thresholds around 800 mGy are published for the risk of cataracts. We hypothesized that surgeon eye exposure during fluoro-assisted DAA total hip arthroplasty would be well below these published thresholds.
Three experienced orthopedic surgeons performed 30 consecutive fluoro-assisted DAA THAs. During each procedure, the surgeon wore a helmet-mounted dosimeter. After 30 consecutive cases, the dosimeters were analyzed. A chart review was then completed to obtain fluoroscopic data saved for each individual case including fluoroscopic time, total radiation dose, and radiation tech experience.
Fluoroscopic data were available for 89 of 90 cases (98.8%). Surgeon 1 had an average fluoroscopic time of 18.51 seconds, radiation dose of 2.396 mGy, and tech experience of 13.06 years. Surgeon 2 had an average fluoroscopic time of 15.63 seconds, radiation dose of 2.139 mGy, and tech experience of 23.69 years. Surgeon 3 had an average fluoroscopic time of 11.06 seconds, radiation dose of 1.462 mGy, and tech experience of 16.03 years. The dosimeter results were 8, 5, and <1 mrem, respectively, for each surgeon. The mean total radiation dose per case for all surgeons was 2.00 mGy (±1.31), and there was no correlation between radiation dose and radiologic tech experience (0.089, P > .05) or radiation dose and patients' body mass index (0.260, P = .014).
Each surgeon would need to perform >300,000 DAA THAs to exceed the 800-mGy cataract threshold dose. The decision to wear protective glasses should be at the surgeon's discretion; however, the findings in this study show a very low radiation dose to the surgeon's eye regardless of radiologic tech experience or patient's body mass index.
在过去十年中，全髋关节置换术（THA）直接前路入路（DAA）的应用有所增加，术中常使用荧光透视来确认植入物位置、腿长和偏移量。已公布辐射暴露阈值约800 mGy时存在白内障风险。我们推测在荧光透视辅助DAA全髋关节置换术中外科医生眼睛的暴露量将远低于这些已公布的阈值。
三位经验丰富的骨科医生连续进行了30例荧光透视辅助DAA THA手术。在每个手术过程中，外科医生佩戴头盔式剂量仪。连续完成30例手术后，对剂量仪进行分析。然后完成病历审查以获取为每个病例保存的荧光透视数据，包括荧光透视时间、总辐射剂量和放射技术经验。
90例病例中的89例（98.8%）有荧光透视数据。外科医生1的平均荧光透视时间为18.51秒，辐射剂量为2.396 mGy，技术经验为13.06年。外科医生2的平均荧光透视时间为15.63秒，辐射剂量为2.139 mGy，技术经验为23.69年。外科医生3的平均荧光透视时间为11.06秒，辐射剂量为1.462 mGy，技术经验为16.03年。每位外科医生的剂量仪结果分别为8、5和<1 mrem。所有外科医生每例手术的平均总辐射剂量为2.00 mGy（±1.31），辐射剂量与放射技术经验之间无相关性（0.089，P>.05），辐射剂量与患者体重指数之间也无相关性（0.260，P = .014）。
每位外科医生需要进行超过300,000例DAA THA手术才会超过800 mGy的白内障阈值剂量。是否佩戴防护眼镜应由外科医生自行决定；然而，本研究结果表明，无论放射技术经验或患者体重指数如何，外科医生眼睛所受辐射剂量都非常低。
