MedPath

FDG PET/MR Imaging of Peripheral Pain Generators

Recruiting
Conditions
Pain
Nociceptive Pain
Interventions
Drug: FDG radiotracer
Device: PET/MRI
Device: PET/CT imaging
Registration Number
NCT06171659
Lead Sponsor
University of Wisconsin, Madison
Brief Summary

The purpose of this research is to determine if a PET/MRI scan using FDG can accurately identify the source of chronic pain. Identifying the source of pain may help doctors treat chronic pain more effectively. Approximately 128 participants will be enrolled and can expect to be on study for up to 12 months.

Detailed Description

The investigators aim to precisely localize sites of increased inflammation and potentially pain generation and improve understanding of nociception and inflammation using a unique, hybrid PET/MRI approach in conjunction with intravenously, administered fluorodeoxyglucose (FDG), which has been shown with PET imaging to be an sensitive surrogate marker of inflammation.

The Primary Objective of this pilot prospective, observational research is to determine whether this approach, which combines PET/MRI and an FDA-approved radiotracer, 18F-Fluorodeoxyglucose (FDG), can accurately localize the sites of painful inflammation in individuals with persistent pain.

* Determine if increased FDG uptake on PET as measured by standard uptake value (SUV) or target-to-background (TTB) measurements is increased in area of pain symptoms when compared to same corresponding areas in healthy, asymptomatic volunteers.

* Determine whether amount of FDG uptake as measured on PET is able to localize to abnormalities when compared to MR imaging (T2 signal intensity, morphologic aberrations)

Secondary Objectives:

* Verify that the standard administered adult dose of FDG (0.14 mCi/kg/patient) used currently in the clinics can also be used to detect peripheral pain generators.

* Verify that FDG uptake in asymptomatic, healthy controls will be significantly less than their chronic pain cohorts at the same anatomic location.

* Determine whether longitudinal FDG PET/MR imaging findings in individual patients directly correlate with symptoms as they evolve over time in joint arthroplasty subjects with PPSP.

* Determine if FDG PET/MR imaging findings spatially differ between different pain types.

Recruitment & Eligibility

Status
RECRUITING
Sex
All
Target Recruitment
128
Inclusion Criteria

Persistent Post-Surgical Pain Patients

  • 18-85 years old
  • Presents with persistent pain with pain score of ≥4 on Numerical Rating Scale [0:10] for at least 6 months following joint arthroplasty or arthroscopy.
  • Able and willing to provide informed consent
  • Willing and able to undergo PET/MRI (arthroplasty and arthroscopy participants) and PET/CT (arthroplasty participants only)

Inclusion Criteria: Asymptomatic controls

  • 18-85 years old
  • Asymptomatic (pain score of ≤2 on the NRS) for at least 6 months following joint arthroplasty or arthroscopy.
  • Able and willing to provide informed consent
  • Willing and able to undergo PET/MRI
Exclusion Criteria
  • Inability to understand and communicate with the investigators to complete the study-related questionnaires.
  • Any co-morbidity which results in severe systemic disease limiting function as defined by the American Society of Anesthesiology (ASA) physical status classification > 3, such as the presence of current or past (6 months) pulmonary, hepatic, renal disease, arthritis, hematopoietic, and neurological diseases not related to chronic pain.
  • Pregnant or breastfeeding. (Individuals with childbearing potential will be asked to verbally confirm they are not pregnant. If they cannot confirm, they will have a urine pregnancy test either at the imaging study visit or within 7 days prior to the imaging study visit.)
  • Subject with contraindication(s) to or inability to undergo PET/MRI
  • Current diagnosis of malignancy of any kind. Participants in remission for at least two years and not undergoing any treatment may be considered per investigator discretion
  • Current enrollment in a scientific interventional or treatment study.
  • Subject unable or unwilling to provide informed consent

Study & Design

Study Type
OBSERVATIONAL
Study Design
Not specified
Arm && Interventions
GroupInterventionDescription
Asymptomatic: Had Total Joint Replacement (Arthroplasty)PET/MRIAsymptomatic subjects who have undergone total hip or total knee arthroplasty. - single scan during one study visit (up to 3.5 hours)
Open Surgical Procedure (Arthroplasty)PET/CT imagingPPSP subjects who have undergone hip (or knee) joint arthroplasty (i.e., open surgical procedure for joint replacement). * 6 month post-op scans * 12 month post-op scans * 18 month post-op scans
Less Invasive Procedure (Arthroscopy)PET/MRIPPSP subjects who have undergone hip (or knee) arthroscopy (i.e., less invasive joint surgical procedure involving scopes and lower profile surgical tools) - 6 month post-op scans
Asymptomatic: Less Invasive Procedure (Arthroscopy)PET/MRIAsymptomatic subjects who have undergone hip or knee arthroscopy. - single scan during one study visit (up to 3.5 hours)
Less Invasive Procedure (Arthroscopy)FDG radiotracerPPSP subjects who have undergone hip (or knee) arthroscopy (i.e., less invasive joint surgical procedure involving scopes and lower profile surgical tools) - 6 month post-op scans
Asymptomatic: Had Total Joint Replacement (Arthroplasty)PET/CT imagingAsymptomatic subjects who have undergone total hip or total knee arthroplasty. - single scan during one study visit (up to 3.5 hours)
Open Surgical Procedure (Arthroplasty)PET/MRIPPSP subjects who have undergone hip (or knee) joint arthroplasty (i.e., open surgical procedure for joint replacement). * 6 month post-op scans * 12 month post-op scans * 18 month post-op scans
Asymptomatic: Had Total Joint Replacement (Arthroplasty)FDG radiotracerAsymptomatic subjects who have undergone total hip or total knee arthroplasty. - single scan during one study visit (up to 3.5 hours)
Asymptomatic: Less Invasive Procedure (Arthroscopy)FDG radiotracerAsymptomatic subjects who have undergone hip or knee arthroscopy. - single scan during one study visit (up to 3.5 hours)
Open Surgical Procedure (Arthroplasty)FDG radiotracerPPSP subjects who have undergone hip (or knee) joint arthroplasty (i.e., open surgical procedure for joint replacement). * 6 month post-op scans * 12 month post-op scans * 18 month post-op scans
Less Invasive Procedure (Arthroscopy)PET/CT imagingPPSP subjects who have undergone hip (or knee) arthroscopy (i.e., less invasive joint surgical procedure involving scopes and lower profile surgical tools) - 6 month post-op scans
Asymptomatic: Less Invasive Procedure (Arthroscopy)PET/CT imagingAsymptomatic subjects who have undergone hip or knee arthroscopy. - single scan during one study visit (up to 3.5 hours)
Primary Outcome Measures
NameTimeMethod
SUVmax (chronic pain vs healthy)baseline
Change in SUVmax (chronic pain)baseline (6 months post-op), 12 months post-op, 18 months post-op
Location of Pain Compared to Target-to-Background (TTB) or SUVmaxbaseline
Secondary Outcome Measures
NameTimeMethod
Number of Participants Where Standard FDG dose was sufficient to detect region of pain (symptomatic groups)baseline

The standard administered adult dose of FDG currently used in clinics is 0.14 mCi/kg/patient.

Variation of the maximum ratio of SUV (SUVRmax) in asymptomatic controls vs symptomaticbaseline
Variation of the maximum ratio of SUV (SUVRmax) in symptomatic participantsbaseline (6 months post-op), 12 months post-op, 18 months post-op
Change in Pain Scores (chronic pain)baseline (6 months post-op), 12 months post-op, 18 months post-op

Pain will be evaluated on a scale of 0 (no pain) to 10 (worse possible pain).

Radiology Review Scoresup to 18 months post-op

Radiologists will evaluate MRI and CT images from each exam, and assign 1 point to any abnormality detected in the following compartments: prosthesis itself, bone, joint space, joint capsule, muscle, subcutaneous fat, and skin, for a total of 7 possible points. Differences in scoring from MRI vs CT images will be further investigated with a t-test.

Trial Locations

Locations (1)

UW School of Medicine and Public Health

🇺🇸

Madison, Wisconsin, United States

© Copyright 2025. All Rights Reserved by MedPath