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Investigation of random lasing as a feedback mechanism for tissue differentiation during laser surgery
Martin Hohmann1,2, Dominique Dörner1, Fanuel Mehari1,2
1Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Institute of Photonic Technologies (LPT), Konrad-Zuse-Straßse 3/5, 91052 Erlangen, Germany.
Abstract:
Laser surgery provides clean, fast and accurate cutting of tissue. However, it is difficult to detect what kind of tissue is being cut. Therefore, a wrong cut may lead to iatrogenic damage of structures. A feedback system should automatically stop the cutting process when a nerve is reached or accidentally being cut to prevent its damage. This could increase the applicability and safety of using a laser scalpel in surgical procedures. In this study, random lasing (RL) is used to differentiate between skin, fat, muscle and nerve tissue. Among these tissue types, a special emphasis is made on the differentiation of nerve from the rest of the tissues, especially fat since nerve is covered by a fatty layer. The differentiation is done for ex-vivo tissues of a pig animal model. The results show that random lasing can be used to differentiate these tissue types also under room light conditions in open air.
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