Translator Disclaimer
13 May 1998 Comparison of transient measurements of infrared radiation and stress waves for practical ablation monitoring during photorefractive keratectomy
Author Affiliations +
Proceedings Volume 3254, Laser-Tissue Interaction IX; (1998) https://doi.org/10.1117/12.308179
Event: BiOS '98 International Biomedical Optics Symposium, 1998, San Jose, CA, United States
Abstract
We compared infrared radiation measurement with stress wave measurement for real-time ablation monitoring during photorefractive keratectomy (PRK). We estimated temperature elevation which may be one of the most effective parameter for PRK monitoring, because the ablation mechanism is mainly attributed to thermal kinetics. The temperature elevation of ablated cornea was evaluated by the infrared radiation and the stress wave. The thermal radiation from irradiated cornea was detected by a MCT detector. The measured signal increased sharply just after the laser irradiation and decreased quasi- exponentially. We could calculate the temperature elevation by observed signal using Stefan-Boltzmann radiation law. In the case of the gelatin gel (15% wt) ablation in vitro, the temperature elevation was 97 deg. at 208 mJ/cm2 in the laser fluence. We also measured transient stress wave by the acoustic transducer which was made by polyvinylidene fluoride (PVDF) film. The temperature elevation could be calculated from the peak stress amplitude based on the short pulsed laser ablation theory. The good agreement on the temperature elevation was obtained between the infrared and the stress based estimations. Due to non-contact and non-invasive method, our infrared measurements for temperature elevation monitoring may be available to accomplish the feedback control on the PRK.
© (1998) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
Miya Ishihara, Tsunenori Arai, Makoto Kikuchi, Hironori Nakano, Satoko Kawauchi, and Minoru Obara "Comparison of transient measurements of infrared radiation and stress waves for practical ablation monitoring during photorefractive keratectomy", Proc. SPIE 3254, Laser-Tissue Interaction IX, (13 May 1998); https://doi.org/10.1117/12.308179
PROCEEDINGS
6 PAGES


SHARE
Advertisement
Advertisement
Back to Top