Požar Tomaž, Petkovšek Rok
Faculty of Mechanical Engineering, University of Ljubljana, Aškerčeva 6, 1000 Ljubljana, Slovenia.
Biomed Opt Express. 2019 Dec 23;11(1):432-447. doi: 10.1364/BOE.11.000432. eCollection 2020 Jan 1.
During laser-induced, breakdown-based medical procedures in human eyes such as posterior capsulotomy and vitreolysis, shock waves are emitted from the location of the plasma. A part of these spherically expanding transients is reflected from the concave surface of the corneal epithelium and refocused within the eye. Using a simplified experimental model of the eye, the dominant secondary cavitation clusters were detected by high-speed camera shadowgraphy in the refocusing volume, dislocated from the breakdown position and described by an abridged ray theory. Individual microbubbles were detected in the preheated cone of the incoming laser pulse and radially extending cavitation filaments were generated around the location of the breakdown soon after collapse of the initial bubble. The generation of the secondary cavitation structures due to shock wave focusing can be considered an adverse effect, important in ophthalmology.
在诸如后囊切开术和玻璃体溶解术等针对人眼的基于激光诱导击穿的医疗手术过程中，冲击波从等离子体位置发射出来。这些呈球形扩展的瞬态信号的一部分会从角膜上皮的凹面反射，并在眼内重新聚焦。使用简化的眼睛实验模型，通过高速相机阴影成像在重新聚焦区域检测到占主导地位的二次空化簇，它们偏离击穿位置，并由简化射线理论描述。在入射激光脉冲的预热锥中检测到单个微气泡，并且在初始气泡坍塌后不久，在击穿位置周围产生了径向延伸的空化丝。由于冲击波聚焦导致的二次空化结构的产生可被视为一种不良影响，在眼科领域具有重要意义。
