Abstract
To investigate the effect of pulsing on neodymium-YAG laser-induced hyperthermia we have exposed rat liver to low-power Nd-YAG laser light delivered via an interstitially inserted fibre. This was either continuous wave excitation or pulsed excitation at 10 or 40 Hz (pulse duration 100μs) with an average power of 1W and exposure durations of 400 s. No differences were seen with respect to overall diameter of the histological damage, diameter of the central cavitation, or intrahepatic temperatures, as measured by an embedded array of microthermocouples. We conclude that with 100-μs pulses, within the range of parameters studied, the pulsing rate does not influence the nature or the extent of damage seen after low-power interstitial Nd-YAG laser hyperthermia.
This is a preview of subscription content, log in via an institution to check access.
Similar content being viewed by others
References
Matthewson K, Coleridge-Smith P, O'Sullivan JP, Northfield TC, Bown SG. Biological effects of intrahepatic Nd YAG laser photocoagulation.Gut 1986,27:A597
Matthewson K, Barton T, Lewin MR et al. Low powered Nd YAG laser treatment of colonic tumours.Gut 1986,27:A600
Deckelbaum LI, Isner JM, Donaldson RF et al. Reduction in laser induced pathologic tissue injury using pulsed energy delivery.Am J Cardiol 1985,56:662–7
Grundfest WS, Litvack IF, Goldenberg T et al. Pulsed ultra-violet lasers and the potential for safe laser angioplasty.Am J Surg 1985,150:220–6
Svaasand LO, Boerslid T, Oeveraasen M. Thermal and optical properties of living tissue: application to laser induced hyperthermia.Lasers Surg Med 1985,5:589–602
Boulnois JL. Photophysical processes in recent medical laser developments: a review.Lasers Med Sci 1986,1:47–66
Hayes JR, Wolbarsht ML. Thermal model for retinal damage induced by pulsed lasers.Aerosp Med 1968,39:474–80
Anderson RR, Parrish JA. Selective photothermolysis: precise microsurgery by selective absorption of pulsed radiation.Science (Wash DC) 1983,220:524–7
Mordon S, Brunetaud JM, Mosquet L et al. Pulsed Nd YAG laser: study with an infra-red camera. In: Joffe SN et al (eds)Neodymium YAG Laser in Medicine and Surgery, Amsterdam: Elsevier Scientific Publishing, 1983
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Matthewson, K., Coleridge-Smith, P., Northfield, T.C. et al. Comparison of continuous-wave and pulsed excitation for interstitial neodymiurn-YAG laser-induced hyperthermia. Laser Med Sci 1, 197–201 (1986). https://doi.org/10.1007/BF02040238
Received:
Issue Date:
DOI: https://doi.org/10.1007/BF02040238