Development of a thulium (Tm:YAP) laser system for brain tissue ablation

Date
2011
Authors
Bilici, T.
Mutlu, S.
Kalaycioglu H.
Kurt, A.
Sennaroglu, A.
Gulsoy, M.
Advisor
Supervisor
Co-Advisor
Co-Supervisor
Instructor
Source Title
Lasers in Medical Science
Print ISSN
0268-8921
Electronic ISSN
Publisher
Volume
26
Issue
5
Pages
699 - 706
Language
English
Type
Article
Journal Title
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Volume Title
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Abstract

In this study, a thulium (Tm:YAP) laser system was developed for brain surgery applications. As the Tm:YAP laser is a continuous-wave laser delivered via silica fibers, it would have great potential for stereotaxic neurosurgery with highest local absorption in the IR region. The laser system developed in this study allowed the user to set the power level, exposure time, and modulation parameters (pulse width and on-off cycles). The Tm:YAP laser beam (200-600 mW, 69-208 W/cm 2) was delivered from a distance of 2 mm to cortical and subcortical regions of ex-vivo Wistar rat brain tissue samples via a 200-μm-core optical fiber. The system performance, dosimetry study, and ablation characteristics of the Tm:YAP laser were tested at different power levels by maximizing the therapeutic effects and minimizing unwanted thermal side-effects. The coagulation and ablation diameters were measured under microscope. The maximum ablation efficiency (100 × ablation diameter/coagulation diameter) was obtained when the Tm:YAP laser system was operated at 200 mW for 10 s. At this laser dose, the ablation efficiency was found to be 71.4% and 58.7% for cortical and subcortical regions, respectively. The fiber-coupled Tm:YAP laser system in hence proposed for the delivery of photothermal therapies in medical applications. © 2011 Springer-Verlag London Ltd.

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Book Title
Keywords
1980-nm, Ablation efficiency, Brain tissue ablation, Thulium laser, glass fiber, silicon dioxide, animal tissue, article, brain cortex, brain surgery, brain tissue, brain tissue ablation, controlled study, dosimetry, ex vivo study, gray matter, infrared radiation, laser, microscope, nonhuman, on off cycle, phototherapy, physical parameters, power level, priority journal, process optimization, pulse width, radiation absorption, radiation dose, radiation exposure, rat, stereotaxic surgery, subcortex, thermocoagulation, thulium yttrium aluminum perovskite laser, white matter, Animals, Brain, Laser Therapy, Rats, Rats, Wistar, Thulium
Citation
Published Version (Please cite this version)