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Title: Influence of laser parameters on selective retinal treatment using single-phase heat transfer analyses

Abstract

Selective thermal treatment to retina is induced by short pulsed lasers to denaturize retinal pigment epithelium (RPE) selectively, while sparing the sensitive photoreceptors. The problem associated with the usage of short pulsed laser is the difficulty in determining the correct dosimetry parameters. This study quantifies the influence of laser parameters over the therapeutic range. The laser-tissue interaction is numerically investigated by analyzing the transient temperature in ocular tissues during the treatment. The rate process analysis for thermal injury is employed to estimate the selective damage of retina. The contours of Arrhenius integral value ({omega}/{omega}{sub max}) presented in this study show both the area and magnitude of damage caused by various laser parameters. Results reveal that the 2 {mu}s pulsed laser with green wavelength and Gaussian profile is relatively more effective for selective retinal treatment. The repetition frequency of 100 Hz is found to produce selectively RPE damage, while higher frequencies produce collateral damage to neural retina and choroid located within 2 {mu}m from the RPE interface.

Authors:
; ; ;  [1];  [2];  [2]
  1. Department of Mechanical Engineering and Department of Biomedical Engineering, University of Cincinnati, Cincinnati, Ohio 45221-0072 (United States)
  2. (United States)
Publication Date:
OSTI Identifier:
20951313
Resource Type:
Journal Article
Resource Relation:
Journal Name: Medical Physics; Journal Volume: 34; Journal Issue: 5; Other Information: DOI: 10.1118/1.2718731; (c) 2007 American Association of Physicists in Medicine; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
62 RADIOLOGY AND NUCLEAR MEDICINE; DAMAGE; DOSIMETRY; DRUGS; EPITHELIUM; HEAT TRANSFER; HEAT TREATMENTS; INJURIES; LASERS; RETINA; RHODOPSIN; THERAPY; UVEA

Citation Formats

Banerjee, Rupak K., Zhu Liang, Gopalakrishnan, Pradeep, Kazmierczak, Michael J., Department of Mechanical Engineering, University of Maryland Baltimore County, Baltimore, Maryland 21250, and Department of Mechanical Engineering, University of Cincinnati, Cincinnati, Ohio 45221-0072. Influence of laser parameters on selective retinal treatment using single-phase heat transfer analyses. United States: N. p., 2007. Web. doi:10.1118/1.2718731.
Banerjee, Rupak K., Zhu Liang, Gopalakrishnan, Pradeep, Kazmierczak, Michael J., Department of Mechanical Engineering, University of Maryland Baltimore County, Baltimore, Maryland 21250, & Department of Mechanical Engineering, University of Cincinnati, Cincinnati, Ohio 45221-0072. Influence of laser parameters on selective retinal treatment using single-phase heat transfer analyses. United States. doi:10.1118/1.2718731.
Banerjee, Rupak K., Zhu Liang, Gopalakrishnan, Pradeep, Kazmierczak, Michael J., Department of Mechanical Engineering, University of Maryland Baltimore County, Baltimore, Maryland 21250, and Department of Mechanical Engineering, University of Cincinnati, Cincinnati, Ohio 45221-0072. Tue . "Influence of laser parameters on selective retinal treatment using single-phase heat transfer analyses". United States. doi:10.1118/1.2718731.
@article{osti_20951313,
title = {Influence of laser parameters on selective retinal treatment using single-phase heat transfer analyses},
author = {Banerjee, Rupak K. and Zhu Liang and Gopalakrishnan, Pradeep and Kazmierczak, Michael J. and Department of Mechanical Engineering, University of Maryland Baltimore County, Baltimore, Maryland 21250 and Department of Mechanical Engineering, University of Cincinnati, Cincinnati, Ohio 45221-0072},
abstractNote = {Selective thermal treatment to retina is induced by short pulsed lasers to denaturize retinal pigment epithelium (RPE) selectively, while sparing the sensitive photoreceptors. The problem associated with the usage of short pulsed laser is the difficulty in determining the correct dosimetry parameters. This study quantifies the influence of laser parameters over the therapeutic range. The laser-tissue interaction is numerically investigated by analyzing the transient temperature in ocular tissues during the treatment. The rate process analysis for thermal injury is employed to estimate the selective damage of retina. The contours of Arrhenius integral value ({omega}/{omega}{sub max}) presented in this study show both the area and magnitude of damage caused by various laser parameters. Results reveal that the 2 {mu}s pulsed laser with green wavelength and Gaussian profile is relatively more effective for selective retinal treatment. The repetition frequency of 100 Hz is found to produce selectively RPE damage, while higher frequencies produce collateral damage to neural retina and choroid located within 2 {mu}m from the RPE interface.},
doi = {10.1118/1.2718731},
journal = {Medical Physics},
number = 5,
volume = 34,
place = {United States},
year = {Tue May 15 00:00:00 EDT 2007},
month = {Tue May 15 00:00:00 EDT 2007}
}
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