Apparatus for detecting cataractogenesis using quasielastic light scattering

Claim 2

Apparatus for in vivo inspection of ocular tissue, comprising: means for producing substantially monochromatic, coherent, collimated light; means for focusing the light on a specific measurement location of a subject's ocular tissue; means for collecting the light scattered by the ocular tissue, the scattered light having an intensity subject to temporal fluctuations; means for producing an electrical signal representative of the temporal fluctuations; means for analyzing the electrical signal to measure the relative average intensity of the light scattered by slow moving protein aggregates in the ocular tissue (I s ) and the relative average intensity of the light scattered by fast moving protein species in the ocular tissue (I f ); and means for locating the position of a first member of the group of measurements consisting of I s , I f , and their sum I tot on a universal curve defined by the relationship of the first member of the group to a second member of the group, the position on the curve corresponding to the degree of cataractogenesis at the specific measurement location in the ocular tissue of the subject.

Claim 3

The apparatus of claim 1 wherein the means for producing substantially monochromatic, coherent, collimated light comprises a laser.

Claim 4

The apparatus of claim 1 wherein the first member is I s and the second member is I tot .

Claim 5

The apparatus of claim 1 wherein the means for analyzing the electrical signal comprises: means for measuring the temporal fluctuations represented by the signal; means for calculating a power spectrum associated with the temporal fluctuations; and means for utilizing the power spectrum to measure I s and I tot .

Claim 6

The apparatus of claim 4 wherein the means for producing substantially monochromatic, coherent, collimated light comprises a laser.

Claim 7

The apparatus of claim 4 wherein the means for calculating a power spectrum associated with the fluctuations is a computer.

Claim 8

The apparatus of claim 4 wherein the means for producing the electrical signal is a photomultiplier tube.

Claim 9

The apparatus of claim 4 wherein the means for focusing the light comprises a slit lamp biomicroscope.

Claim 10

The apparatus of claim 4, further comprising means for displaying the relationship of at least one member of the group consisting of I s , I f and I tot to another member.

Claim 11

The apparatus of claim 5 wherein the means for calculating a power spectrum associated with the fluctuations is a computer.

Claim 12

The apparatus of claim 10 wherein the means for producing the electrical signal is a photomultiplier tube.

Claim 13

The apparatus of claim 11 wherein the means for focusing the light comprises a slit lamp biomicroscope.

Claim 14

The apparatus of claim 1 wherein the means for analyzing the electrical signal comprises: means for measuring the temporal fluctuations represented by the signal; means for calculating an autocorrelation function associated with the temporal fluctuations; and means for utilizing the autocorrelation function to measure I f and I s .

Claim 15

The apparatus of claim 2 wherein the means for calculating an autocorrelation function is a computer.

Claim 16

The apparatus of claim 2 wherein the means for producing the electrical signal is a photomultiplier tube.

Claim 17

The apparatus of claim 2 wherein the means for focusing the light comprises a slit lamp biomicroscope.

Claim 18

The apparatus of claim 2, further comprising means for displaying the relationship of at least one member of the group consisting of I s , I f and I tot to another member.

Claim 19

The apparatus of claim 13 wherein the means for producing substantially monochromatic, coherent, collimated light comprises a laser.

Claim 20

The apparatus of claim 18 wherein the means for calculating an autocorrelation function is a computer.

Claim 21

The apparatus of claim 19 wherein the means for producing the electrical signal is a photomultiplier tube.

Claim 22

The apparatus of claim 20 wherein the means for focusing the light comprises a slit lamp biomicroscope.

Claim 23

Apparatus for in vivo inspection of ocular tissue, comprising: means for producing substantially monochromatic, coherent, collimated light; means for focusing the light on a specific measurement location of a subject's ocular tissue; means for collecting the light scattered by the ocular tissue, the scattered light having an intensity subject to temporal fluctuations; an optical square law transducer for producing an electrical signal representative of the temporal fluctuations; means for analyzing the electrical signal to measure the relative average intensity of the light scattered by slow moving protein aggregates in the ocular tissue (I s ) and the relative average intensity of the light scattered by fast moving protein species in the ocular tissue (I f ); and means for locating the position of a first member of the group of measurements consisting of I s , I f , and their sum I tot on a universal curve defined by the relationship of the first member of the group to a second member of the group, the position on the curve corresponding to the degree of cataractogenesis at the specific measurement location in the ocular tissue of the subject.

Claim 24

Apparatus for in vivo inspection of ocular tissue, comprising: means for producing substantially monochromatic, coherent, collimated light; means for focusing the light on a specific measurement location of a subject's ocular tissue; means for collecting the light scattered by the ocular tissue, the scattered light having an intensity subject to temporal fluctuations; an optical square law transducer for producing an electrical signal representative of the temporal fluctuations; means for analyzing the electrical signal to measure the relative average intensity of the light scattered by slow moving protein aggregates in the ocular tissue (I s ) and the relative average intensity of the light scattered by fast moving protein species in the ocular tissue (I f ); and means for locating the position of a first member of the group of measurements consisting of I s , I f , and their sum I tot on a universal curve defined by the relationship of the first member of the group to a second member of the group, the position on the curve corresponding to the degree of cataractogenesis at the specific measurement location in the ocular tissue of the subject.

Claim 25

The apparatus of claim 22 wherein the means for analyzing the electrical signal comprises: means for measuring the temporal fluctuations represented by the signal; means for calculating an autocorrelation function associated with the temporal fluctuations; and means for utilizing the autocorrelation function to measure I f and I s .

Claim 26

The apparatus of claim 22 wherein the means for analyzing the electrical signal comprises: mean for measuring the temporal fluctuations represented by the signal; means for calculating a power spectrum associated with the temporal fluctuations; and means for utilizing the power spectrum to measure I s and I tot .

Claim 27

The apparatus of claim 22 wherein the means for producing substantially monochromatic, coherent, collimated light comprises a laser.

Claim 28

The apparatus of claim 22 wherein the optical square law transducer is a photomultiplier tube.

Claim 29

The apparatus of claim 22 wherein the optical square law transducer is a solid-state photodiode.

Claim 30

The apparatus of claim 22 wherein the means for focusing the light comprises a slit lamp biomicroscope.

Claim 31

The apparatus of claim 22 wherein the first member is I s and the second member is I tot .

Claim 32

The apparatus of claim 25 wherein the means for producing substantially monochromatic, coherent, collimated light provides approximately one milliwatt of light power.

Claim 33

The apparatus of claim 24 wherein the means for calculating a power spectrum associated with the fluctuations is a computer.

Claim 34

The apparatus of claim 24, further comprising means for displaying the relationship of I s and I tot .

Claim 35

The apparatus of claim 23 wherein the means for calculating an autocorrelation function is a computer.

Claim 36

The apparatus of claim 23, further comprising means for displaying the relationship of at least one member of the group consisting of I s , I f and I tot to another member.

Claim 37

Apparatus of in vivo inspection of ocular tissue, comprising: means for producing substantially monochromatic, coherent, collimated light; means for focusing the light on a specific measurement location of a subject's ocular tissue; means for collecting the light scattered by the ocular tissue, the scattered light having an intensity subject to temporal fluctuations; an optical square law transducer for producing an electrical signal representative of the temporal fluctuations; means for analyzing the electrical signal to measure the relative average intensity of the light scattered by slow moving protein aggregates in the ocular tissue (I s ) and the relative average intensity of the light scattered by fast moving protein species in the ocular tissue (I f ); means for providing at least two members of a group of measurements consisting of I s , I f and their sum, I tot , from each of a plurality of subjects; and means for using the measurements from each of the plurality of subjects to produce a universal curve defined by the relationship of one member of the group to another member of the group, wherein a position of a measurement taken in the ocular tissue of a particular subject on the universal curve corresponds to the degree of cataractogenesis at the particular measurement location in the ocular tissue of the particular subject.

Claim 38

Apparatus of in vivo inspection of ocular tissue, comprising: means for producing substantially monochromatic, coherent, collimated light; means for focusing the light on a specific measurement location of a subject's ocular tissue; means for collecting the light scattered by the ocular tissue, the scattered light having an intensity subject to temporal fluctuations; an optical square law transducer for producing an electrical signal representative of the temporal fluctuations; means for analyzing the electrical signal to measure the relative average intensity of the light scattered by slow moving protein aggregates in the ocular tissue (I s ) and the relative average intensity of the light scattered by fast moving protein species in the ocular tissue (I f ); means for providing at least two members of a group of measurements consisting of I s , I f and their sum, I tot , from each of a plurality of subjects; and means for using the measurements from each of the plurality of subjects to produce a universal curve defined by the relationship of one member of the group to another member of the group, wherein a position of a measurement taken in the ocular tissue of a particular subject on the universal curve corresponds to the degree of cataractogenesis at the particular measurement location in the ocular tissue of the particular subject.

Claim 39

The apparatus of claim 35 wherein the means for producing substantially monochromatic, coherent, collimated light comprises a laser.

Claim 40

The apparatus of claim 35 wherein the means for analyzing the electrical signal comprises: means for measuring the temporal fluctuations represented by the signal; means for calculating an autocorrelation function associated with the temporal fluctuations; and means for utilizing the autocorrelation function to measure I f and I s .

Claim 41

The apparatus of claim 37 wherein the means for calculating an autocorrelation function is a computer.

Claim 42

The apparatus of claim 37, further comprising means for displaying the relationship of at least one member of the group consisting of I s , I f and I tot to another member.

Claim 43

The apparatus of claim 37 wherein the means for producing substantially monochromatic, coherent, collimated light comprises a laser.

Claim 44

The apparatus of claim 40 wherein the means for producing substantially monochromatic, coherent, collimated light provides approximately one milliwatt of light power.

Claim 45

The apparatus of claim 35 wherein the means for analyzing the electrical signal comprises: means for measuring the temporal fluctuations represented by the signal; means for calculating a power spectrum associated with the temporal fluctuations; and means for utilizing the power spectrum to measure I s and I tot .

Claim 46

The apparatus of claim 42 wherein the means for calculating a power spectrum associated with the fluctuations is a computer.

Claim 47

The apparatus of claim 42, further comprising means for displaying the relationship of I s and I tot .

Claim 48

The apparatus of claim 35 wherein the optical square law transducer is a photomultiplier tube.

Claim 49

The apparatus of claim 35 wherein the optical square law transducer is a solid-state photodiode.

Claim 50

The apparatus of claim 35 wherein the means for focusing the light comprises a slit lamp biomicroscope.

Claim 51

The apparatus of claim 35 wherein the first member is I s and the second member is I tot .

Claim 52

Apparatus for in vivo inspection of ocular tissue, comprising: means for producing substantially monochromatic, coherent, collimated light; means for focusing the light on a specific measurement location of a subject's ocular tissue; means for collecting the light scattered by the ocular tissue, the scattered light having an intensity subject to temporal fluctuations; means for producing an electrical signal representative of the temporal fluctuations; means for analyzing the electrical signal to measure the relative average intensity of the light scattered by slow moving protein aggregates in the ocular tissue (I s ) and the relative average intensity of the total light (I tot ) scattered by the sum of both fast moving protein species and the slow moving protein species in the ocular tissue; and means for locating the position of the point designated by (I s , I tot ) on a universal curve defined by the relationship of tot to I s , the position on the curve corresponding to the degree of cataractogenesis at the specific measurement location in the ocular tissue of the subject.

Claim 53

Apparatus for in vivo inspection of ocular tissue, comprising: means for producing substantially monochromatic, coherent, collimated light; means for focusing the light on a specific measurement location of a subject's ocular tissue; means for collecting the light scattered by the ocular tissue, the scattered light having an intensity subject to temporal fluctuations; means for producing an electrical signal representative of the temporal fluctuations; means for analyzing the electrical signal to measure the relative average intensity of the light scattered by slow moving protein aggregates in the ocular tissue (I s ) and the relative average intensity of the total light (I tot ) scattered by the sum of both fast moving protein species and the slow moving protein species in the ocular tissue; and means for locating the position of the point designated by (I s , I tot ) on a universal curve defined by the relationship of tot to I s , the position on the curve corresponding to the degree of cataractogenesis at the specific measurement location in the ocular tissue of the subject.

Claim 54

The apparatus of claim 49 wherein the means for analyzing the electrical signal comprises: means for measuring the temporal fluctuations represented by the signal; means for calculating an autocorrelation function associated with the temporal fluctuations; and means for utilizing the autocorrelation function to measure I f and I s .

Claim 55

The apparatus of claim 50 wherein the means for producing substantially monochromatic, coherent, collimated light comprises a laser.

Claim 56

The apparatus of claim 51 wherein the means for calculating an autocorrelation function is a computer.

Claim 57

The apparatus of claim 52 wherein the optical square law transducer is a photomultiplier tube.

Claim 58

The apparatus of claim 53 wherein the means for focusing the light comprises a slit lamp biomicroscope.

Claim 59

The apparatus of claim 50 wherein the means for calculating an autocorrelation function is a computer.

Claim 60

The apparatus of claim 50 wherein the means for producing the electrical signal is a photomultiplier tube.

Claim 61

The apparatus of claim 50 wherein the means for focusing the light comprises a slit lamp biomicroscope.

Claim 62

The apparatus of claim 50, further comprising means for displaying the relationship of at least one member of the group consisting of I s , I f and I tot to another member.

Claim 63

The apparatus of claim 49 wherein the means for producing substantially monochromatic, coherent, collimated light comprises a laser.