Diagnostic method for high sensitivity detection of component concentrations in human gas emissions

A diagnostic method for high sensitivity detection of component concentrations in human gas emissions comprising:

• (a) collecting a gas sample in a gas cell, wherein the gas sample may contain a specified component being associated with a plurality of fundamental absorption peak frequencies;
• (b) passing a tunable optical radiation beam through the gas cell when the gas cell (1) contains a reference sample having a known concentration of the specified component and (2) contains the gas sample, wherein the frequency of the tunable optical radiation beam comprises a modulation frequency superimposed on a base frequency, and the base frequency is swept repeatedly through a series of frequencies such that the series of frequencies comprises at least one of the fundamental absorption peak frequencies;
• (c) measuring, after the tunable optical beam passes through the gas cell, as first signal outputs the amplitude of an optoacoustic signal in the gas cell detected by an acoustic microphone, and as a second signal of the tunable optical radiation beam at the modulation frequency, and as second signal outputs a power of the tunable optical radiation beam;
• and
• (d) determining a concentration of the specified component in the gas sample using the first signal outputs and the second signal outputs obtained from the reference sample and the gas sample.

A skin gas detector comprising:

• a collection chamber housing defining an interior space, said housing having a planar opening on a first side for enclosing and sealing the interior space against skin, a gas outlet on a second side, and a gas inlet on a third side;
• an inert gas source connected to the gas inlet;
• a gas cell connected to the gas outlet and to a vacuum pump so that the vacuum pump may pump gas from the interior space into the gas cell;
• a tunable optical radiation beam directed through the gas cell;
• and
• an energy absorption detection system to measure energy absorbed by the gas within the gas cell.

A method of delivering an optical radiation beam from a single source to a plurality of medical systems comprising the steps of:

• (a) directing the optical radiation beam into a beam guide that branches into a plurality of endpoints;
• (b) placing at each of the plurality of endpoints one of the plurality of medical systems to receive and utilize the optical radiation beam for diagnosis or treatment of a patient;
• (c) monitoring the plurality of medical systems to determine beam utilization requirements of each of the plurality of medical systems;
• (d) directing the optical radiation beam through the beam guide to one or more of the plurality of endpoints based on the beam utilization requirements of each of the plurality of medical systems;

A diagnostic method for high sensitivity detection of component concentrations in human gas emissions comprising:

• (a) collecting a gas sample in a gas cell, wherein the gas sample may contain a specified component being associated with a plurality of fundamental absorption peak frequencies;
• (b) passing a tunable optical radiation beam through the gas cell when the gas cell (1) contains a reference sample having a known concentration of the specified component and (2) contains the gas sample, wherein the frequency of the tunable optical radiation beam comprises a modulation frequency superimposed on a base frequency, and the base frequency is swept repeatedly through a series of frequencies such that the series of frequencies comprises at least one of the fundamental absorption peak frequencies;
• (c) measuring, after the tunable optical beam passes through the gas cell, as first signal outputs an amplitude of the tunable optical radiation beam at the modulation frequency when the gas cell contains the reference sample, as second signal outputs a power of the tunable optical radiation beam when the gas cell contains the reference sample, as third signal outputs the amplitude of the tunable optical radiation beam at the modulation frequency when the gas cell contains the gas sample, and as fourth signal outputs the power of the tunable optical radiation beam when the gas cell contains the gas sample;
• and
• (d) determining a concentration of the specified component in the gas sample using the following equation:
• C
• =
• constant
• ⁢
• ⁢
• 2
• *
• S
• AC
• ⁡
• (
• f
• 1
• ,
• ω
• )
• P
• ⁡
• (
• f
• 1
• )
• ,
• where C corresponds to the concentration of the specified component, f1 corresponds to the at least one fundamental absorption peak frequency, ω corresponds to the modulation frequency, SAC(f1, ω) corresponds to the third signal outputs, P1(f1) corresponds to the fourth signal outputs, and constant2 is determined by solving the equation for constant2 and substituting the first signal outputs for SAC(f1, ω), the second signal outputs for P1(f1), and the known concentration of the reference sample for C.

A diagnostic method for high sensitivity detection of component concentrations in human gas emissions comprising:

• (a) collecting a gas sample in a calorimetric gas cell having an acoustic microphone within said calorimetric gas cell, wherein the gas sample may contain a specified component being associated with a plurality of fundamental absorption peak frequencies;
• (b) passing, at distinct and different times, a pulsed discretely tunable optical radiation beam at a first frequency and at a second frequency through the calorimetric gas cell when the calorimetric gas cell (1) contains a reference sample having a known concentration of the specified component and (2) contains the gas sample, wherein the first frequency is near a first of the fundamental absorption peak frequencies and the second frequency is not near any of the fundamental absorption peak frequencies;
• (c) adjusting the pressure in the calorimetric gas cell to increase an absorption of the specified component at the first frequency;
• (d) measuring, after the optical radiation beam passes through the calorimetric gas cell, as first signal outputs an optoacoustic signal in the calorimetric gas cell detected by the acoustic microphone when the optical radiation beam passes through the gas cell at the first frequency, as second signal outputs the power of the tunable optical radiation beam at the first frequency, as third signal outputs the optoacoustic signal in the calorimetric gas cell detected by the acoustic microphone when the optical radiation beam passes through the gas cell at the second frequency, and as fourth signal outputs the power of the tunable optical radiation beam at the second frequency;
• and
• (e) determining a concentration of the specified component in the gas sample using the first, second, third, and fourth signal outputs.