Work

Depth profiling of laser-heated chromophores in biological tissues by pulsed photothermal radiometry

Year: 1995

Type: article

Abstract: A solution method is proposed to the inverse problem of determining the unknown initial temperature distribution in a laser-exposed test material from measurements provided by infrared radiometry. A Fredholm integral equation of the first kind is derived that relates the temporal evolution of the infrared signal amplitude to the unknown initial temperature distribution in the exposed test material. The singular-value decomposition is used to demonstrate the severely ill-posed nature of the derived inverse problem. Three inversion methods are used to estimate solutions for the initial temperature distribution. A nonnegatively constrained conjugate-gradient algorithm using early termination is found superior to unconstrained inversion methods and is applied to image the depth of laser-heated chromophores in human skin.

Source: Journal of the Optical Society of America A

DOI: 10.1364/josaa.12.001479

Authors: Thomas E. Milner, Dennis M. Goodman, B. Samuel Tanenbaum, J. Stuart Nelson

Institutions: University of California, Irvine, Beckman Laser Institute and Medical Clinic, Lawrence Livermore National Laboratory, Harvey Mudd College

Language: English

Topic: Optical Imaging and Spectroscopy Techniques

Subfield: Radiology, Nuclear Medicine and Imaging

Field: Medicine

Domain: Health Sciences

Open Access status: green

Funders: National Institutes of Health, National Institute of Arthritis and Musculoskeletal and Skin Diseases, National Center for Research Resources