Neurosurgery Research Laboratory, Division of Neurological Surgery, St. Joseph's Hospital and Medical Center, Phoenix, Arizona 85013, USA.
J Neurosurg. 2010 Feb;112(2):434-43. doi: 10.3171/2009.7.JNS09356.
The CO(2) laser has an excellent profile for use in neurosurgery. Its high absorption in water results in low thermal spread, sparing adjacent tissue. Use of this laser has been limited to line-of-sight applications because no solid fiber optic cables could transmit its wavelength. Flexible photonic bandgap fiber technology enables delivery of CO(2) laser energy through a flexible fiber easily manipulated in a handheld device. The authors examined and compared the first use of this CO(2) laser fiber to conventional methods for incising neural tissue.
Carbon dioxide laser energy was delivered in pulsed or continuous wave settings for different power settings, exposure times, and distances to cortical tissue of 6 anesthetized swine. Effects of CO(2) energy on the tissue were compared with bipolar cautery using a standard pial incision technique, and with scalpel incisions without cautery. Tissue was processed for histological analysis (using H & E, silver staining, and glial fibrillary acidic protein immunohistochemistry) and scanning electron microscopy, and lesion measurements were made.
Light microscopy and scanning electron microscopy revealed laser incisions of consistent shape, with central craters surrounded by limited zones of desiccated and edematous tissue. Increased laser power resulted in deeper but not significantly wider incisions. Bipolar cautery lesions showed desiccated and edematous zones but did not incise the pia, and width increased more than depth with higher power. Incisions made without using cautery produced hemorrhage but minimal adjacent tissue damage.
The photonic bandgap fiber CO(2) laser produced reliable cortical incisions, adjustable over a range of settings, with minimal adjacent thermal tissue damage. Ease of application under the microscope suggests this laser system has reached true practicality for neurosurgery.
CO2 激光在神经外科中具有极佳的应用前景。其在水中的高吸收率导致低热扩散，从而保护相邻组织。由于没有固态光纤可以传输其波长，因此该激光的应用仅限于视线应用。灵活的光子带隙光纤技术可通过易于在手持设备中操纵的灵活光纤传输 CO2 激光能量。作者研究并比较了首次使用这种 CO2 激光纤维与传统方法切割神经组织的效果。
CO2 激光能量以脉冲或连续波模式设置，不同功率设置、暴露时间和距离对 6 只麻醉猪的皮质组织进行照射。使用标准软脑膜切口技术，将 CO2 能量与双极电凝进行比较，并与不使用电凝的手术刀进行比较，评估 CO2 能量对组织的影响。对组织进行组织学分析（使用 H&E、银染和胶质纤维酸性蛋白免疫组化）和扫描电子显微镜检查，并进行病变测量。
光镜和扫描电子显微镜显示，激光切口形状一致，中央有凹陷，周围有有限的干燥和水肿组织。增加激光功率会导致更深但不明显更宽的切口。双极电凝病变显示干燥和水肿区，但不切开软脑膜，功率增加时宽度增加大于深度。不使用电凝的切口会产生出血，但相邻组织损伤最小。
光子带隙光纤 CO2 激光可产生可靠的皮质切口，可在一系列设置下进行调节，且相邻组织热损伤最小。在显微镜下易于应用表明该激光系统已真正适用于神经外科。
