Smith Harvey E, Welsch Matthew D, Sasso Rick C, Vaccaro Alexander R
Thomas Jefferson University, Department of Orthopaedic Surgery, Philadelphia, PA 19107, USA.
J Spinal Cord Med. 2008;31(5):532-7. doi: 10.1080/10790268.2008.11753648.
BACKGROUND/OBJECTIVE: Little is known about the long-term effects of chronic exposure to ionizing radiation. Studies have shown that spine surgeons may be exposed to significantly more radiation than that observed in surgery on the appendicular skeleton. Computer-assisted image guidance systems have been shown in preliminary studies to enable accurate instrumentation of the spine. Computer-assisted image guidance systems may have significant application to the surgical management of spinal trauma and deformity. The objective of this study was to compare C-arm fluoroscopy and computer-assisted image guidance in terms of radiation exposure to the operative surgeon when placing pedicle screw-rod constructs in cadaver specimens.
Twelve single-level (2 contiguous vertebral bodies) lumbar pedicle screw-rod constructs (48 screws) in 4 fresh cadavers were placed using standard C-arm fluoroscopy and computer-assisted image guidance (Stealth Station with Iso-C(3D)). Pedicle screw-rod constructs were placed at L1-L2, L3-L4, and L5-S1 in 4 fresh cadaver specimens. Imaging was alternated between C-arm fluoroscopy and computer-assisted image guidance with StealthStation Iso-C(3D). Radiation exposure was measured using ring and badge dosimeters to monitor the thyroid, torso, and index finger. Postprocedure CT scans were obtained to judge accuracy of screw placement.
Mean radiation exposure to the torso was 4.33 +/- 2.66 mRem for procedures performed with standard fluoroscopy and 0.33 +/- 0.82 mRem for procedures performed with computer-assisted image guidance. This difference was statistically significant (P= 0.012). Radiation exposure to the index finger and thyroid was negligible for all procedures. The accuracy of screw placement was similar for both techniques.
Computer-assisted image guidance systems allow for the safe and accurate placement of pedicle screw-rod constructs with a significant reduction in exposure to ionizing radiation to the torso of the operating surgeon.
背景/目的：关于长期暴露于电离辐射的影响，人们了解甚少。研究表明，脊柱外科医生所受辐射可能比在四肢骨骼手术中观察到的要多得多。初步研究显示，计算机辅助图像引导系统能够实现脊柱的精确器械操作。计算机辅助图像引导系统在脊柱创伤和畸形的手术治疗中可能具有重要应用价值。本研究的目的是比较在尸体标本中置入椎弓根螺钉-棒结构时，C形臂荧光透视和计算机辅助图像引导对手术医生的辐射暴露情况。
在4具新鲜尸体上，使用标准C形臂荧光透视和计算机辅助图像引导（带有Iso-C(3D)的Stealth Station）放置12个单节段（2个相邻椎体）腰椎椎弓根螺钉-棒结构（48枚螺钉）。在4具新鲜尸体标本中，于L1-L2、L3-L4和L5-S1处放置椎弓根螺钉-棒结构。成像在C形臂荧光透视和带有StealthStation Iso-C(3D)的计算机辅助图像引导之间交替进行。使用指环式和徽章式剂量仪测量辐射暴露，以监测甲状腺、躯干和食指。术后进行CT扫描以判断螺钉置入的准确性。
标准荧光透视操作时，躯干的平均辐射暴露为4.33±2.66毫雷姆，计算机辅助图像引导操作时为0.33±0.82毫雷姆。这种差异具有统计学意义（P = 0.012）。所有操作中，食指和甲状腺的辐射暴露可忽略不计。两种技术的螺钉置入准确性相似。
计算机辅助图像引导系统能够安全、准确地放置椎弓根螺钉-棒结构，显著减少手术医生躯干所受的电离辐射暴露。
