PET/MRI in the Diagnosis of Chronic Pain

Several studies have implicated involvement of sigma-1 receptors (SR1s) in the generation of chronic pain, while others are investigating anti SR1 drugs for treatment of chronic pain. Using [18F]-FTC-146 and positron emission tomography/magnetic resonance imaging (PET/MRI), the investigators hope to identify the source of pain generation in patients with chronic pain. The purpose of this study is to compare the uptake of [18F]FTC-146 in healthy volunteers to that of individuals suffering from chronic pain.

Chronic pain is a significant, widespread problem affecting every fifth person worldwide. Reported in 2011 by the Institute of Medicine, chronic pain affects 116 million American adults - more than the total number of individuals affected by heart disease, cancer, and diabetes combined. An estimated $635 billion each year is spent in the medical management of chronic pain and lost productivity. Better clinical methods to diagnose and localize pain are needed. The investigators have developed a S1R-specific radiotracer, [18F]FTC-146. Using imaging approaches to assess the location of S1R in pain may provide a tool to diagnose pain generators, monitor treatment response, and aid in the selection of patients for treatment. The goal is to use [18F]FTC-146 to image S1R expression in healthy volunteers and to compare the images to those individuals suffering from pain conditions in the following categories: (1) nociceptive pain (pain that results from tissue injury or inflammation), (2) neuropathic pain (pain that results from direct injury, disruption, impingement/compression or malfunction of the peripheral and/or central nervous system), and (3) mixed pain (pain that appears to have both nociceptive and neuropathic).

Neuropathic Pain, Nociceptive Pain, Mixed Pain (Nociceptive and Neuropathic), Spinal Pain, Radiculopathy, Myelopathy, Neurogenic Claudication

Individuals suffering from nociceptive pain, neuropathic pain, and mixed pain (pain that appears to be both nociceptive and neuropathic) and undergo a [18F]FTC-146 PET/MRI scan.

Biodistribution of [18F]FTC-146 represented as Standardized Uptake Value max (SUVmax) in healthy volunteers.

Biodistribution of [18F]FTC-146 represented as Standardized Uptake Value max (SUVmax) in pain patients.

Inclusion Criteria: Healthy Volunteers: At least 18 years old. Covid Vaccination status: Vaccinated or unvaccinated subjects who received a negative test result from the Covid test within 72 hours of the scan. Pain Patients: At least 18 years old. Chronic pain (nociceptive, neuropathic or mixed pain) lasting greater than 2 months. Pain level of at least 4/10 on a 0-10 Comparative Pain Scale. Covid Vaccination status: Vaccinated or unvaccinated subjects who received a negative test result from the Covid test within 72 hours of the scan. Exclusion Criteria: Healthy Volunteers: Pain Pain Medication MRI incompatible Pregnant or nursing Non-English speaker Claustrophobic Pain Patients: MRI incompatible Pregnant or nursing Non-English speaker Claustrophobic

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