PET Imaging in Chronic Traumatic Encephalopathy

Brain Disease Clinical Trial

Official title: PET Imaging in Chronic Traumatic Encephalopathy

Status Completed

Clinical Trial Summary

Background:

• Chronic traumatic encephalopathy (CTE) is a brain disease caused in part by head injury. The brain changes from CTE can only be seen at autopsy. Researchers want to test a new brain scan to help diagnose CTE in living patients.

Objective:

• To determine if a new type of brain scan can detect changes that occur in chronic traumatic encephalopathy.

Eligibility:

• Adults age 18 60 with previous head injury or participation in certain sports.

Design:

• Participants will be screened with:

• Physical exam

• Blood and urine tests

• Tests of thinking, mood, and memory

• 30-minute magnetic resonance imaging (MRI) brain scan. A magnetic field and radio waves take pictures of the brain. Participants will lie on a table that slides into a metal cylinder. They will get earplugs for the loud knocking sounds.

• Visit 1: Participants will have a 70-minute PET scan of the brain with a small amount of a radioactive chemical. That will be injected through an intravenous tube (catheter) in each arm. A catheter will also be put into an artery at the wrist or elbow.

• Participants will lie on a bed that slides in and out of a donut-shaped scanner. A plastic mask may be molded to their face and head. Vital signs and heart activity will be checked before and during the scan.

• Blood and urine will be taken before and after the scan.

• Participants will be checked on by phone the next day.

• Visit 2: Participants will repeat Visit 1 with a different chemical and no artery catheter.

• Visit 3: Participants may have a spinal tap. Some fluid will be removed by needle between the bones in the back.

Clinical Trial Description

Objective: To determine if the PET radioligand [11C]PBB3 can detect aggregates of tau protein in the brains of patients with history of traumatic brain injury (TBI) and suspected chronic traumatic encephalopathy (CTE).

Study population: The proposed study will include 40 subjects. Twenty will be patients with history of TBI and suspected CTE and 20 will be healthy cognitively normal volunteers without history of TBI.

Design: Subjects will undergo medical screening and have brain MRI and neuropsychological testing performed. Subjects will undergo one brain PET scan with [11C]PBB3 to detect aggregates of tau protein. Subjects will also have one brain PET scan with [11C]Pittsburgh compound B (PIB) to detect amyloid plaques. Subjects will be asked to have a lumbar puncture to measure CSF tau concentrations.

Outcome measures: The primary outcome measure will be the amount of [11C]PBB3 binding in the brain. We will quantify the radioligand s brain uptake, washout, plasma clearance, and distribution volume using compartmental modeling. Distribution volume of [11C]PBB3 is proportional to the density of insoluble paired helical filaments of tau and is equal to the ratio at equilibrium of uptake in brain to the concentration of parent radiotracer in plasma. As an exploratory measure, we will determine if there is a relationship between [11C]PBB3 binding in brain and gray matter loss on MRI. We will also measure the amount of [11C]PIB binding in the brain using the Logan reference tissue method with cerebellum as reference. ;

Related Conditions & MeSH terms

• Brain Disease
• Brain Diseases
• Brain Injuries, Traumatic
• Brain Mapping
• Chronic Traumatic Encephalopathy
• Dementia

• NCT number: NCT02211820
• Study type: Observational
• Source: National Institutes of Health Clinical Center (CC)
• Status: Completed
• Start date: August 1, 2014
• Completion date: October 12, 2016