Michele T Mitchell

US Patent:

56997957, Dec 23, 1997

Filed:

Mar 31, 1995

Appl. No.:

8/415356

Inventors:

Costas Pitris - Austin TX
Michele Follen Mitchell - Houston TX

Assignee:

Board of Regents, The University of Texas System - Austin TX

International Classification:

A61B 600

US Classification:

128634

Abstract:

A probe, and an apparatus incorporating the probe, for detecting tissue abnormality, particularly precancerous cervical tissue, through fluorescence spectroscopy are disclosed. In vivo fluorescence excitation and detection can be accomplished easily and accurately using a probe whose tip conforms to the surface of the cervix. In addition, a higher number of fiber pairs provides more information and, therefore, more accurate diagnosis.

US Patent:

54213398, Jun 6, 1995

Filed:

May 12, 1993

Appl. No.:

8/060432

Inventors:

Nirmala Ramanujam - Austin TX
Anita Mahadevan - Austin TX
Michele F. Mitchell - Houston TX
Sharon Thomsen - Houston TX

Assignee:

Board of Regents, The University of Texas System - Austin TX

International Classification:

A61B 600

US Classification:

128665

Abstract:

Apparatus and in vivo methods to distinguish normal and abnormal cervical tissue and to detect cervical intraepithelial neoplasia (CIN) in a diagnostic cervical tissue sample. Induced fluorescence intensity spectra from known normal cervical tissue and a diagnostic tissue sample are obtained from the same patient. Peak fluorescence intensity values for normal tissue samples are averaged, as are slope measurements from predetermined portions of spectra induced in both known normal cervical tissue and the diagnostic tissue sample. Peak fluorescence intensities of diagnostic tissue spectra are divided by average peak fluorescence intensity values for normal tissue in the same patient to yield relative peak fluorescence intensity values. Normal and abnormal cervical tissues are distinguished using a predetermined empirical discriminant function of slope measurements derived from normal tissue spectra and relative peak fluorescence intensity measurements in the same patient. CIN is distinguished from tissue with human papilloma virus injection or inflammation using a predetermined empirical discriminant function of average slope measurements on spectra from known normal tissue and slope measurements on a diagnostic tissue spectrum.

US Patent:

56973730, Dec 16, 1997

Filed:

Mar 14, 1995

Appl. No.:

8/403446

Inventors:

Nirmala Ramanujam - Austin TX
Anita Mahadevan - Austin TX
Michele Follen Mitchell - Houston TX

Assignee:

Board Of Regents, The University Of Texas System - Austin TX

International Classification:

A61B 600
G01N 2162

US Classification:

128664

Abstract:

A method and apparatus for detecting tissue abnormality, particularly precancerous cervical tissue, through fluorescence or Raman spectroscopy, or a combination of fluorescence and Raman spectroscopy. In vivo fluorescence measurements were followed by in vitro NIR Raman measurements on human cervical biopsies. Fluorescence spectra collected at 337, 380 and 460 nm excitation were used to develop a diagnostic method to differentiate between normal and dysplastic tissues. Using a fluorescence diagnostic method, a sensitivity and specificity of 80% and 67% were observed for differentiating squamous intraepithelial lesions (SILs) from all other tissues. In accordance with another aspect of the invention, using Raman scattering peaks observed at selected wavenumbers, SILs were separated from other tissues with a sensitivity and specificity of 88% and 100%. In addition, inflammation and metaplasia samples are correctly separated from the SILs.

US Patent:

62416626, Jun 5, 2001

Filed:

Oct 20, 1998

Appl. No.:

9/175232

Inventors:

Anant Agrawal - Austin TX
Costas Pitris - Austin TX
Urs Utzinger - Austin TX
Carrie Brookner - Missouri City TX
Michele Follen Mitchell - Houston TX

Assignee:

Lifespex, Inc. - Kirkland WA

International Classification:

A61B 500

US Classification:

600310

Abstract:

A method for using acetic acid as a signal enhancing contrast agent during fluorescence spectroscopy of normal and neoplastic tissue, particularly epithelium. In one aspect, the invention includes a method of detecting tissue abnormality in a diagnostic tissue sample in a patient, comprising the steps of obtaining a first fluorescence intensity spectrum from the diagnostic tissue sample; thereafter, applying acetic acid to the diagnostic tissue sample in sufficient concentration to alter the response of such diagnostic tissue sample to electromagnetic radiation for at least an effective period of time; during the effective period of time, obtaining a second fluorescence intensity spectrum from the diagnostic tissue sample; determining a parameter indicative of a change between the first and second fluorescence emission intensity spectra; and analyzing the determined parameter to determine a probability that the diagnostic tissue sample is normal or abnormal.

US Patent:

56239327, Apr 29, 1997

Filed:

Jun 6, 1995

Appl. No.:

8/469396

Inventors:

Nirmala Ramanujam - Austin TX
Anita Mahadevan - Austin TX
Michele F. Mitchell - Houston TX
Sharon Thomsen - Houston TX

Assignee:

Board of Regents, The University of Texas System - Austin TX

International Classification:

A61B 600

US Classification:

128665

Abstract:

Apparatus and in vivo methods to distinguish normal and abnormal cervical tissue and to detect cervical intraepithelial neoplasia (CIN) in a diagnostic cervical tissue sample. Induced fluorescence intensity spectra from known normal cervical tissue and a diagnostic tissue sample are obtained from the same patient. Peak fluorescence intensity values for normal tissue samples are averaged, as are slope measurements from predetermined portions of spectra induced in both known normal cervical tissue and the diagnostic tissue sample. Peak fluorescence intensities of diagnostic tissue spectra are divided by average peak fluorescence intensity values for normal tissue in the same patient to yield relative peak fluorescence intensity values. Normal and abnormal cervical tissues are distinguished using a predetermined empirical discriminant function of slope measurements derived from normal tissue spectra and relative peak fluorescence intensity measurements in the same patient. CIN is distinguished from tissue with human papilloma virus infection or inflammation using a predetermined empirical discriminant function of average slope measurements on spectra from known normal tissue and slope measurements on a diagnostic tissue spectrum.

US Patent:

60959827, Aug 1, 2000

Filed:

Dec 11, 1997

Appl. No.:

8/988840

Inventors:

Nirmala Ramanujam - Austin TX
Anita Mahadevan - Austin TX
Michele Follen Mitchell - Houston TX

Assignee:

Board of Regents, The University of Texas System - Austin TX

International Classification:

A61B 600

US Classification:

600476

Abstract:

A method and apparatus for detecting tissue abnormality, particularly precancerous cervical tissue, through fluorescence or Raman spectroscopy, or a combination of fluorescence and Raman spectroscopy. In vivo fluorescence measurements were followed by in vitro NIR Raman measurements on human cervical biopsies. Fluorescence spectra collected at 337, 380 and 460 nm excitation were used to develop a diagnostic method to differentiate between normal and dysplastic tissues. Using a fluorescence diagnostic method, a sensitivity and specificity of 80% and 67% were observed for differentiating squamous intraepithelial lesions (SILs) from all other tissues. In accordance with another aspect of the invention, using Raman scattering peaks observed at selected wavenumbers, SILs were separated from other tissues with a sensitivity and specificity of 88% and 100%. In addition, inflammation and metaplasia samples are correctly separated from the SILs.