Assembly and method for objectively measuring pain in a subject

• US 6,018,675 A
• Filed: 05/22/1998
• Issued: 01/25/2000
• Est. Priority Date: 05/22/1998
• Status: Expired due to Fees

• Current Assignee: The Research Foundation for The State University of New York (State University of New York)
• Original Assignee: The Research Foundation for The State University of New York (State University of New York)
• Inventors: Apkarian, A. Vania, Szeverenyi, Nikolaus M.
• Primary Examiner(s): Smith, Ruth S.
• Application Number:
  US09/082,992
• Time in Patent Office: 613 Days
• Field of Search: 600/407, 600/410, 600/411, 600/425, 600/427, 600/555, 600/557, 600/554
• US Class Current: 600/407
• CPC Class Codes: A61B 5/055 involving electronic [EMR] or nuclear [NMR] magnetic resonance, e.g. magnetic resonance imaging
• CPC Class Codes: A61B 5/4824 Touch or pain perception evaluation A61B5/4821 takes precedence
• CPC Class Codes: A61B 5/483 by thermal stimulation

Abstract

A device and methodology is disclosed for the objective measurement of pain in awake human subjects. A variable intensity painful stimulus is given to the subject in a time dependent manner, the patient'"'"'s brain responses are recorded using an appropriate imaging modality (e.g. functional MR) while the subject indicates the level of discomfort using a "perceptometer" or other similar pain rating device. The pain rating is correlated with the imaging results using a quantitative analysis to characterize the brain'"'"'s representation of this pain. Color overlays are generated on high resolution anatomical images (MR or other modality) of the brain summarizing the calculated pain related analysis information.

Claims

1. An assembly for objectively measuring pain, said assembly comprising

an imaging device for recording and imaging a sequence of brain responses of a subject over a time period and for emitting a trigger signal in response to each imaged brain response;

a subject controlled pain rating device for emitting a signal corresponding to a subject-perceived level of discomfort of the subject; and

a computer interface for correlating each of the sequence of brain responses to said signal corresponding to levels of discomfort in dependence on said trigger signals.

2. An assembly as set forth in claim 1 wherein said imaging device is a functional magnetic resonance imaging device.

3. An assembly as set forth in claim 2 wherein said pain rating device includes a pair of spring biased pivotally mounted arms for movement from a relaxed position towards a stressed position in response to a digitally applied force from the subject to indicate a level of discomfort.

4. An assembly as set forth in claim 1 which further comprises means for applying a variable pain-inducing stimulus to the subject over said time period and said imaging device is a functional magnetic resonance imaging device.

5. An assembly for measuring changes in pain, said assembly comprising

an imaging device for recording and imaging a sequence of brain images of a subject over a time period and emitting a trigger signal in response to each image;

a first computer for collecting the sequence of brain images from said imaging device and emitting information corresponding thereto;

first means for applying a variable painful stimulus to the subject during said time period;

a pain rating device for indicating levels of discomfort of the subject to said variable painful stimulus over said time period;

a second computer operatively connected to said first means for controlling said first means to vary said stimulus at selected times during said time period and operatively connected to said pain rating device to record changes in the levels of discomfort and to emit information corresponding thereto and connected to said imaging device to receive said trigger signals; and

a data analysis computer for receiving said information emitted from said first computer and said information emitted from said second computer to produce a record correlating changes in said brain images in response to changes in said stimulus relative to indicated levels of discomfort.

6. An assembly as set forth in claim 5 wherein said imaging device is a functional magnetic resonance imaging device.

7. An assembly as set forth in claim 5 wherein said pain rating device includes a pair of spring biased pivotally mounted arms for movement from a relaxed position towards a stressed position in response to a digitally applied force from the subject to indicate a level of discomfort.

8. An assembly as set forth in claim 5 wherein said first means applied a thermal stimulus to the subject.

9. A method of objectively measuring pain in a subject, said method comprising the steps of

applying a variable painful stimulus to a subject in a time dependent manner;

objectively imaging brain responses of the subject during application of said stimulus;

recording subjective indications of the level of discomfort of the subject during application of said stimulus; and

correlating said subjective indications of the level of discomfort with said objectively imaged brain responses to characterize the brain'"'"'s representation of the pain associated with said stimulus.

10. A method of objectively measuring pain in a subject, said method comprising the steps of

subjecting a subject to a variable pain over a period of time;

objectively imaging brain responses of the subject during said period of time;

recording subjective indications of the level of discomfort of the subject during said time period; and

correlating said subjective indications of the level of discomfort with said objectively imaged brain responses to characterize the brain'"'"'s representation of the pain.

11. A method as set forth in claim 10 wherein said step of subjecting a subject to a variable pain includes external manipulation of the subject.

12. A method as set forth in claim 10 wherein said step of subjecting a subject to a variable pain includes application of an external stimulus.

13. A method as set forth in claim 12 wherein the external stimulus is a thermal stimulus.

14. A method as set forth in claim 10 wherein the brain responses are imaged with a magnetic resonance imaging device.

15. A method of identifying brain regions involved in pain perception comprising the steps of

objectively imaging brain responses of a subject over a period of time to obtain a sequence of brain images;

recording subjective indications of the level of pain of the subject during said period of time; and

correlating said subjective indications with said sequence of brain images to identify brain regions corresponding to a subjective level of pain.