Luminal diagnostics employing spectral analysis

• US 6,129,667 A
• Filed: 02/02/1998
• Issued: 10/10/2000
• Est. Priority Date: 02/02/1998
• Status: Expired due to Fees

• Current Assignee: General Electric Company
• Original Assignee: General Electric Company
• Inventors: Darrow, Robert David, Dumoulin, Charles Lucian, Watkins, Ronald Dean
• Primary Examiner(s): Lateef, Marvin M.
• Assistant Examiner(s): SHAW, SHAWNA JEANNINE
• Application Number:
  US09/017,565
• Time in Patent Office: 981 Days
• Field of Search: 600/473, 600/475, 600/476, 600/477, 600/478, 600/424, 600/342, 600/343, 600/310, 600/410, 600/420, 600/407, 600/137, 600/117, 600/160, 600/182, 356/345, 356/346
• US Class Current: 600/424
• CPC Class Codes: A61B 1/00183 for variable viewing angles
• CPC Class Codes: A61B 5/0075 by spectroscopy, i.e. measuring spectra, e.g. Raman spectroscopy, infrared absorption spectroscopy A61B5/0071 takes precedence
• CPC Class Codes: A61B 5/0084 for introduction into the body, e.g. by catheters A61B5/1459 takes precedence
• CPC Class Codes: A61B 5/02007 Evaluating blood vessel condition, e.g. elasticity, compliance
• CPC Class Codes: A61B 5/055 involving electronic [EMR] or nuclear [NMR] magnetic resonance, e.g. magnetic resonance imaging
• CPC Class Codes: A61B 5/06 Devices, other than using radiation, for detecting or locating foreign bodies for removing same A61B17/50 ; determining position of probes within or on the body of the patient
• CPC Class Codes: A61B 5/062 using magnetic field
• CPC Class Codes: A61B 8/0841 for locating instruments

Abstract

An invasive probe for determining the morphological characteristics of walls of a lumen employs a real-time tracking means and an optical spectral measurement means. As the probe is advanced within the lumen, the real-time tracking means provides three-dimensional coordinates of the probe'"'"'s position and orientation. Concurrent with probe localization, measurement of the spectral properties of the lumen wall are made by detecting the reflectance and/or absorption of light at the lumen wall. Both the probe position and the spectral measurement are sent to a data acquisition system which in turn provides an graphic or numeric display to the operator. Probe tracking can be performed with radio-frequency, magnetic resonance, ultrasonic techniques or the like. If desired, spectral measurements can be made in the visible, ultra-violet or infra-red spectral bands to provide optimized detection of chemical species of interest.

Claims

1. A system for creating a tissue map of a lumen within a subject comprising:

a) an invasive device for insertion into a subject;

b) an optical spectrum acquisition device in an insertion end of the invasive device, disposed to project a light beam to irradiate the lumen at an angular displacement θ

around the insertion end of the invasive device, and to receive reflected light, the optical spectrum acquisition device being adapted to create a signal representing the light spectrum reflected from the lumen, and the optical spectrum acquisition device being adapted to measure a respective diameter of the lumen at a respective location of the invasive device within the lumen;

c) at least one device locating means attached to the insertion end of the invasive device;

d) a tracking means for tracking locations of the device locating means within the subject;

e) a rotation sensor for measuring the angular displacement θ

of the irradiating beam;

f) a storage device capable of storing an indication of tissue type and corresponding 3D locations for later retrieval;

g) a display;

h) a look up device coupled to each of the following;

the optical spectrum acquisition device, the storage device, the display, the tracking means and the rotation sensor, the look up device being configured to convert the tracked location from the tracking means in correspondence with the angular displacement of the irradiating beam and the respective diameter, to estimate a 3D location of the lumen reflecting the irradiating beam, said look up device to correlate the reflected light spectrum to a color frequency stored in the look up device indicating a tissue type, to store the tissue type along with the 3D location represented in the storage device, and to display the 3D locations and corresponding tissue type as a tissue map on the display.

2. The system for creating a tissue map of lumen of claim 1 further comprising:

an interferometer device operating to receive the reflected light, to accurately determine a distance D from the lumen to the optical spectrum acquisition device, and provides it to look up device to more accurately determine the 3D location on the lumen reflecting the irradiating beam, resulting in tissue maps incorporating actual measured lumen diameters.

3. The system for creating a tissue map of lumen of claim 1 wherein the an optical spectrum acquisition device comprises:

a) a fiber optic cable running through the invasive device having an optical port at one end and the other end being an equipment end;

b) a light source coupled to the equipment end of the fiber optic cable operating to create an outgoing light beam O and pass it through the fiber optic cable and out the optical port;

c) an angled rotating mirror attached to the optical port end of the fiber optic cable, having a mirror angled with respect to an axis though the light beam, and capable of rotating substantially about this axis upon rotation of the fiber optic cable, operating to reflect the outgoing beam O to the lumen and the reflected beam R from said lumen back in the opposite direction;

d) a planar mirror for reflecting the outgoing light beam O from the optical port back toward the rotating mirror causing it to reflect laterally to impinge upon said lumen, and for reflecting the return beam back R into the optical port;

e) a detector coupled to the equipment end of optical cable, for converting the reflected beam R into an electronic signal; and

f) a spectrum analyzer coupled to the detector and the look up device, operating to extract spectral information from the electronic signal from detector, and provide it to look up device for tissue determination.

4. The system for creating a tissue map of lumen of claim 1 further comprising:

a user interface for interacting with an operator to acquire operator define input and operating to provide this input to the lookup device.

5. A system for indicating tissue type of a lumen within a subject comprising:

a) an invasive device for insertion into a subject;

b) means for projecting a light beam to irradiate the lumen and to receive reflected light from the lumen, the projecting means being adapted to create a signal representing the light spectrum from the lumen and the projecting means further being adapted to measure a respective diameter of the lumen at a location within the lumen;

c) a tracking means for tracking locations of the invasive device; and

,

d) means for receiving the reflected light spectrum, respective diameter measurements, and tracked locations and correlating the reflected light spectrum to a color frequency indicative of tissue type characteristic stored in the receiving and correlating means to indicate the tissue type of the lumen at said tracked locations.

6. The system for indicating tissue type of a lumen of claim 5 wherein the projecting means is configured to project a light beam to irradiate the lumen at an angular displacement θ

around an insertion end of the invasive device.

7. The system for indicating tissue type of a lumen of claim 6 further comprising:

a) the invasive device being movable within the subject by an operator; and

,

b) at least one device locating means attached to invasive device;

c) the receiving and correlating means being coupled to the tracking means and adapted to indicate the tissue type of the lumen according to operator movement of the invasive device.

8. The system for indicating tissue type of a lumen of claim 7 further comprising a display and means for displaying indicated tissue type on the display.