Yu Xiao-Bo, Miller Joseph, Yu Paula K, Cringle Stephen J, Balaratnasingam Chandrakumar, Morgan William H, Yu Dao-Yi
Centre for Ophthalmology and Visual Science, The University of Western Australia, Perth, Australia.
Invest Ophthalmol Vis Sci. 2009 Aug;50(8):3729-36. doi: 10.1167/iovs.08-3109. Epub 2009 Apr 1.
To explore the tissue ablation properties of pulsed 266-nm and 213-nm laser radiation in porcine retina and the potential for 213-nm laser radiation to cut through human trabecular meshwork.
Segments of porcine retinas were used, and localized areas of tissue were exposed to 266-nm or 213-nm laser. Human trabecular meshwork from donor eyes was also ablated using pulsed 213-nm laser. Ocular tissue was bathed in fluid to mimic the intraocular environment. Single or multiple pulses at various fluence levels were delivered with a tapered fiber-optic probe. The tissue was then fixed for histologic examination. Ablation depth and extent of damage were measured and related to fluence level and number of pulses applied.
Ablation of the inner retina was achieved by single pulses at fluence levels of 0.6 J/cm(2) and higher with 266-nm laser radiation and 0.2 J/cm(2) and higher with 213-nm laser radiation. At the same fluence, ablation depth was greater (P < 0.001) with 213-nm than 266-nm laser, with less collateral damage. Ablation of human trabecular meshwork using 213-nm laser was highly dependent on fluence after exposure to single and multiple pulses, allowing good control of ablation depth.
Laser radiation at 213 nm has greater ablation efficiency, less collateral damage, and a more linear dose-response than ablation at 266 nm. Precise removal of human trabecular meshwork was demonstrated using pulsed 213-nm laser radiation.
探讨脉冲266纳米和213纳米激光辐射对猪视网膜的组织消融特性，以及213纳米激光辐射穿透人小梁网的可能性。
使用猪视网膜切片，将局部组织区域暴露于266纳米或213纳米激光下。也使用脉冲213纳米激光对供体眼的人小梁网进行消融。眼组织浸泡在液体中以模拟眼内环境。通过锥形光纤探头以不同的能量密度水平发射单个或多个脉冲。然后将组织固定以进行组织学检查。测量消融深度和损伤范围，并将其与能量密度水平和施加的脉冲数相关联。
使用266纳米激光辐射，能量密度水平为0.6 J/cm²及以上的单个脉冲可实现视网膜内层的消融；使用213纳米激光辐射，能量密度水平为0.2 J/cm²及以上的单个脉冲可实现视网膜内层的消融。在相同能量密度下，213纳米激光的消融深度大于266纳米激光（P < 0.001），且附带损伤较小。使用213纳米激光对人小梁网进行消融高度依赖于单个和多个脉冲照射后的能量密度，从而能够很好地控制消融深度。
与266纳米消融相比，213纳米激光辐射具有更高的消融效率、更小的附带损伤以及更线性的剂量反应。使用脉冲213纳米激光辐射证明了可以精确切除人小梁网。
