Share Email Print

Journal of Biomedical Optics

Reflectance imaging of the human retina at 810 nm does not suffice to optimize the parameters of hydrodynamic rebalancing laser treatment
Author(s): Filippo M. Piffaretti; Jean-Pierre Ballini; Roberto Perotti; Matthieu Zellweger; Edoardo Vezzola; Michel Sickenberg; Georges A. Wagnières
Format Member Price Non-Member Price
PDF $20.00 $25.00

Paper Abstract

The hydrodynamic rebalancing laser (HRL) procedure is an ophthalmic therapy based on the administration of subthreshold infrared (810 nm) laser light to selected areas on the retina to treat various retina diseases. Heterogeneities of tissue response are observed, including undesired retinal damages. Variations of tissue absorbance were hypothesized to cause this uneven response. Irradiation parameters (diameter=100  μm; power=1  W; irradiation time: 50 to 200 ms), location and tissue response were studied in 16 patients (20 eyes, 2535 laser spots) to discover any correlation between tissue response and normalized fundus reflectance at 810 nm. The results demonstrate a complex relationship between some pathologies and occurrences of retinal damage, but no clear correlation. One possible reason is that the resolution of reflectance images is insufficient to see "small" (40 μm or less) absorption centers, particularly deep-seated ones. Additionally, tissue parameters other than variations of the fundus optical absorption influence heat diffusion and temperature increases. Monitoring or individualizing the light dose in HRL therapy, or any similar infrared diode laser-based therapy will require more sophisticated technologies, including imaging the retina's reflectance with an improved resolution, as well as refined methods to detect complex correlations between retinal damage and specific pathologies.

Paper Details

Date Published: 22 November 2012
PDF: 10 pages
J. Biomed. Opt. 17(11) 116027 doi: 10.1117/1.JBO.17.11.116027
Published in: Journal of Biomedical Optics Volume 17, Issue 11
Show Author Affiliations
Filippo M. Piffaretti, Ecole Polytechnique Fédérale de Lausanne (Switzerland)
Jean-Pierre Ballini, Ecole Polytechnique Fédérale de Lausanne (Switzerland)
Roberto Perotti, Save Sight Foundation (Italy)
Matthieu Zellweger, Ecole Polytechnique Fédérale de Lausanne (Switzerland)
Edoardo Vezzola, Save Sight Foundation (Italy)
Michel Sickenberg, Save Sight Foundation (Switzerland)
Georges A. Wagnières, Ecole Polytechnique Fédérale de Lausanne (Switzerland)

© SPIE. Terms of Use
Back to Top