United States Patent m tm Patent Number: 5,137,355
Barbour et al.  Date of Patent: Aug. 11,1992
 METHOD OF IMAGING A RANDOM MEDIUM
 Inventors: Randall L. Barbour, Westbury; Jack Lubowsky, Merrick; Raphael Aronson, Great Neck, all of N.Y.
 Assignee: The Research Foundation of State University of New York, Albany, N.Y.
 Appl. No.: 363,075
 Filed: Jun. 8,1989
Related U.S. Application Data
 Continuation-in-part of Ser. No. 204,101, Jun. 8, 1988.
 Int. CI.* G01N 21/00
 U.S. CI 356/342; 128/664;
 Field of Search 356/342, 237; 128/633,
128/664, 665; 250/358.1
 References Cited
U.S. PATENT DOCUMENTS
4,555,179 11/1985 Langerholc et al 356/237
4,810,875 3/1989 Wyatt 250/227.11
4,829,184 5/1989 Nelson et al 250/358.1
Langerholc, J. "Moving Phase Transitions in Laser-Ir
radiated Biological Tissue" Applied Optics vol. 18, No. 13 (Jul. 1, 1979).
Primary Examiner—Richard A. Rosenberger
Attorney, Agent, or Firm—Morgan & Finnegan
A non-invasive medical imaging technique capable of evaluating, in situ, the oxygenation state of body tissues (e.g., by measuring the spectral properties of heme proteins) is described. The technique is based on the measurement of scattered radiation in the near-infrared region (NIR), where significant penetration into body tissues occurs. The disclosed technique employs a multi-wavelength collimated source and a collimated receiver and performs a positional arid angular scan of the scattered radiation for each position of the incident beam. The resultant data is evaluated by employing imaging schemes which give differential weights to the contribution of various volume elements (voxels) in the medium to the detector response. A three-dimensional spectroscopic image of the target medium is determined by considering the contribution of the various volume elements for each source-detector configuration and position of the incident beam at various frequencies. These measurements, in an imaging mode, yield vital physiological information while being, for example, a sensitive indicator of subtle physiological stress caused by disease or trauma.
23 Claims, 7 Drawing Sheets