US 5,349,961 A · Method and apparatus for in vivo optical spectroscopic examination

Abstract

Methodology and apparatus for the clinical evaluation of biological matter, in particular human anatomy, examined in situ and in vivo, by selective spectral light transmissivity. An optical probe introduces selected light spectra into the examination subject at a first position and resulting light intensity at a second position located some distance from the infusion point is measured; also, light reception preferably occurs at at least one other location, and the effective distances between these locations and the infusion point are determined. The light energy received at the distant points is quantified and conditioned by use of the effective distances from the infusion point and/or from one another, and also by contrasting the data from the two differently-located reception points, such that the resulting data quantitatively characterizes intrinsic internal tissue characteristics in an absolute sense, devoid of particular individual characteristics and variations such as skin pigmentation, boundary composition or state, etc. The methodology is especially characterized by the selection and use of particularly-located first and second light-reception positions whose locations with respect to the point at which the light spectra are introduced define particular zones of interrogation and analysis, and whose location with respect to one another may be comparatively examined (e.g., differenced) to selectively define a particular internal volume whose structure or conditional state is to be examined, quantified, and/or analyzed, all of which is accomplished on a non-intrusive in vivo basis.

Claims27

Dependent claims

A method of non-obtrusively and non-invasively by optical response the conditional state of physiological substance located within a particular internal volume inside a test subject, comprising the steps:

introducing light of selected wavelengths into said subject from a source location outside of said subject;
selecting at least first and second light-detection locations on said subject at points spaced from one another and spaced from said source by unequal first and second distances such that a first mean optical path is established extending between said source and said first detection location and a second mean optical path of a length different than that of said first mean optical path is established between the source and said second detection location, said second path generally defining an overall internal volume containing said particular internal volume and said first optical path generally defining a secondary internal volume located at least partially within said overall internal volume but disposed generally nearer said source location than said particular internal volume;
detecting the light resulting from said introduced light at said first and second locations and producing signals representative of such detected light;
and
processing said signals to obtain optical response data which particularly characterizes selected attributes of said particular internal volume substantially without effects attributable to said secondary internal volume.

2 more elements

A method of appraising internal structure within selected organic bodies and materials having an outer perimeter, wherein electromagnetic energy is used as an investigative media by passing it through said perimeter and at least internal portions of said bodies and materials and producing quantitative data from such energy which characterizes composition, condition and/or physiology of a particular area inside said bodies and materials, comprising the steps of:

operatively coupling source and receiver members to a selected body or material and sending electromagnetic energy of selected wavelengths from said source member into and through the selected body or material to said receiver members;
receiving resulting electromagnetic energy from said body or material at separate and mutually-spaced first and second locations, said first location being nearer that of said source than said second location;
quantifying the resulting energy which is received at said first location as well as quantifying the resulting energy received at said second location to obtain characteristic response data values;
and
using said data values for said first location to condition the said data values for said second location by modifying one such set of quantified data values as a function of the other, to thereby remove effects attributable to impingement of the electromagnetic energy upon and passage thereof through the outer perimeter of said selected body or material, whereby quantified response data valuations are obtained which characterize the composition, condition and/or physiology of a particular internal portion of said body or material on a generally intrinsic basis and which are substantially independent of characteristics attributable to said perimeter.

2 more elements

Apparatus for obtaining optical response data from organic bodies which is representative of internal tissue within such bodies, including:

at least one optical probe member including a source and at least two receivers adapted for placement in operational proximity with selected areas on a perimeter of said body and adapted to pass light of selected wavelengths from said source to said receivers through said perimeter and internal tissue;
means for holding said source and receivers in predetermined relation while in their said positions of operational proximity to the selected areas on the said body;
said receivers including means for receiving the resulting light which has passed through said body at a first position with respect to said light source as well as means for receiving such light at a second position located further away from said source than said first position, and for producing corresponding signals representative of data values for each such position which are correlated with said selected wavelengths;
and
means for receiving said signals and producing data values therefrom which characterize the light received at one such position as a function of corresponding light received at the other such position by differencing the value of one such signal from that of another in pairs of correlated signal values, such that the resulting data values comprise representations of intrinsic characteristics of said internal tissue and are generally free of optical effects resulting from factors attributable to impingement of the light upon and passage thereof through the said perimeter of said body and are primarily representative of the conditioned state of a particular internal tissue volume whose location within said body is determined by the particular location and disposition of said first and second light-receiving positions relative one another.

2 more elements

In a method of conducting non-invasive clinical patient examinations by in vivo spectrometry, wherein selected wavelengths of electromagnetic energy are introduced into the patient at a first location and resultant amounts of such energy are received at at least one second location, and wherein there is a desired area to be examined which is disposed internally within the patient beyond said first and second locations, the improvement in analyzing said resultant amounts of energy to obtain data which characterizes said desired area comprising:

determining the approximate length of a generally arcuate locus extending from said first location to said second location,
measuring said received resultant amounts of energy, and
conditioning measurements of said received resultant amounts of energy as a function of a mean path length traveled by said energy between said first and second location by using said length of said locus as said mean path length.

Dependencies are inferred from the claim text.

Method and apparatus for in vivo optical spectroscopic examination

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Method and apparatus for in vivo optical spectroscopic examination

Life of this patent

Abstract

Claims27