Positron Emission Tomography to Measure Pain and Pain Control

NCT00001307 | Completed

• 2 other identifiers: 92024392-D-0243
• Study Type: observational
• Target: 273
• Locations: 1 country
• Sites: 1

Brief Summary

This study will examine how the brain processes pain signals and how the different parts of the brain work with each other in response to painful stimuli. A better understanding of how people experience pain may be helpful in developing more effective treatments. Healthy normal volunteers, patients requiring third molar (wisdom tooth) extraction, and patients with persistent pain due to disease, injury or other reason may be eligible for this study. Participants will receive one or more of the following sensory stimuli, which may cause brief discomfort or pain:

• Heat/Cold - applied by an electronically controlled device that touches the skin, or by temperature-controlled water baths, or by a thermally controlled brass cylinder the subject grasps
• Capsaicin (active ingredient in hot chili peppers) - injected in a small volume of fluid under the skin or into a muscle
• Mechanical stimulation - brushings or vibrations that do not normally cause pain
• Ischemic stimulation - inflation of a blood pressure cuff on the arm or leg for up to 30 minutes These stimuli will be applied both before and during positron emission tomography (PET) scanning. This test shows which parts of the brain are active and which are not and is important for studying how different parts of the brain work together to feel and react to specific sensations. For this procedure, the subject lies on a table in the PET scanner while a series of scans are taken during different sensory conditions. At the beginning of each scan, radioactive water is injected into an arm vein through a catheter (a thin plastic tube). A special camera records the arrival and disappearance of the radiation in various brain areas, creating a picture of the brain's activity in various regions. Oral surgery patients may have PET scans both before and after their wisdom tooth extraction. Alfentanil, a commonly used narcotic pain reliever, will also be given during the PET procedure to determine how the brain responds to sensory stimuli while under the effects of a pain killer. Participants will also have a magnetic resonance imaging (MRI) scan of the brain to help interpret the PET results. MRI uses a magnetic field and radio waves to show structural and chemical changes in tissues. During the scan, the subject lies on a table in a cylindrical machine (the scanner). He or she can speak with a staff member via an intercom system. Some sensory studies may require placing an arterial and/or intravenous line. Following injection of a local anesthetic, a catheter is placed in an artery in the arm. At regular intervals during various sensory stimuli, small blood samples are drawn from the artery to measure blood gases and other substances. Samples may also be drawn from a catheter placed in a vein. Subjects may also have ultrasound monitoring to evaluate blood flow in the arteries, veins and brain. A gel is spread over the skin above the blood vessel and a hand-foot-and-mouth device is placed on the gel. The device emits high-frequency sound waves to produce a picture of the speed of blood flow in the artery and the diameter of the vessel.

Conditions

Healthy; Hyperalgesia; Pain; Peripheral Nervous System Disease

Keywords

Analgesia; PET; Positron Emission; Functional Brain Imaging; Allodynia; Thalamus; Somatosensory Cortex; Reflex Sympathetic Dystrophy; Normal Volunteer; Chronic Pain

Interventions

Oxygen-15 Water DRUG

Capsaicin DRUG

Eligibility Criteria

• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Child (0-17), Adult (18-64), Older Adult (65+)

You may qualify if:

• Healthy Normal Volunteers between the ages of 18 and 80 years
• Certain Chronic Pain Patients

You may not qualify if:

• Structural or Functional Brain Defects
• Metallic Surgical Implants
• Chronic Drug Treatments

Sponsors & Collaborators

• National Institute of Dental and Craniofacial Research (NIDCR): lead

Study Sites (1)

National Institute of Dental And Craniofacial Research (NIDCR)

Bethesda, Maryland, 20892, United States

Location

Related Publications (3)

• Casey KL, Minoshima S, Berger KL, Koeppe RA, Morrow TJ, Frey KA. Positron emission tomographic analysis of cerebral structures activated specifically by repetitive noxious heat stimuli. J Neurophysiol. 1994 Feb;71(2):802-7. doi: 10.1152/jn.1994.71.2.802.

  PMID: 8176441 BACKGROUND

• Coghill RC, Talbot JD, Evans AC, Meyer E, Gjedde A, Bushnell MC, Duncan GH. Distributed processing of pain and vibration by the human brain. J Neurosci. 1994 Jul;14(7):4095-108. doi: 10.1523/JNEUROSCI.14-07-04095.1994.

  PMID: 8027764 BACKGROUND

• Coghill RC, Mayer DJ, Price DD. The roles of spatial recruitment and discharge frequency in spinal cord coding of pain: a combined electrophysiological and imaging investigation. Pain. 1993 Jun;53(3):295-309. doi: 10.1016/0304-3959(93)90226-F.

  PMID: 8351159 BACKGROUND

MeSH Terms

Conditions

Hyperalgesia; Pain; Peripheral Nervous System Diseases; Agnosia; Reflex Sympathetic Dystrophy; Chronic Pain

Interventions

Capsaicin

Condition Hierarchy (Ancestors)

Somatosensory Disorders; Sensation Disorders; Neurologic Manifestations; Nervous System Diseases; Signs and Symptoms; Pathological Conditions, Signs and Symptoms; Neuromuscular Diseases; Perceptual Disorders; Neurobehavioral Manifestations; Complex Regional Pain Syndromes; Autonomic Nervous System Diseases

Intervention Hierarchy (Ancestors)

Polyunsaturated Alkamides; Amides; Organic Chemicals; Alkenes; Hydrocarbons, Acyclic; Hydrocarbons; Catechols; Phenols; Benzene Derivatives; Hydrocarbons, Aromatic; Hydrocarbons, Cyclic; Solanaceous Alkaloids; Alkaloids; Heterocyclic Compounds; Fatty Acids, Monounsaturated; Fatty Acids, Unsaturated; Fatty Acids; Lipids

Study Design

• Study Type: observational
• Sponsor Type: NIH

Study Record Dates

• First Submitted: November 3, 1999
• First Posted: November 4, 1999
• Study Start: August 1, 1992
• Study Completion: August 1, 2005
• Last Updated: March 4, 2008

Record last verified: 2005-08

Locations

US (1)