Recruiting

Safety of repeated contrast dye use in brain imaging over five years

Plain-English translation of NCT04373564 on ClinicalTrials.gov ↗ · Source last updated January 2026 · Translation generated June 2026 · How we translate trials

Phase 4 — The treatment has already been approved. Researchers are tracking how it works in a large number of people over time.

What is this trial?

This trial is tracking whether gadolinium-based contrast agents — special dyes injected before brain scans to help doctors see images more clearly — might affect how your brain works over time. Researchers will compare people who receive repeated injections of gadolinium with people who don't receive it, measuring memory, thinking ability, and movement over 5 years to make sure the dye is safe.

Gadolinium contrast dye has been used safely in medical imaging for decades, but researchers want to confirm that when patients need multiple scans over many years, the dye doesn't gradually build up in the body or affect brain function.

Do you qualify?

You likely qualify if…

you are neurologically healthy with no unstable brain or mental health conditions
you are already scheduled for multiple brain or body MRI scans over the next 5 years for medical reasons (such as cancer screening, liver monitoring, or pancreatic surveillance)
you are willing to have brain imaging scans at the start and end of the study
you will receive at least 5 contrast dye injections with the same type of dye throughout the 5-year study period

You likely don't qualify if…

you have a history of neurological conditions like stroke, multiple sclerosis, or Parkinson's disease
you have been diagnosed with severe, active depression, bipolar disorder, or any psychotic disorder in the past 2–5 years
you have had brain surgery or have epilepsy
you have received different types of contrast dye in the past and medical records don't clearly show which type you received

What participation looks like

If you join the contrast dye group, you'll continue receiving your regularly scheduled contrast-enhanced MRI scans as part of your medical care — the study doesn't add extra scans for treatment purposes. You'll also complete yearly memory and movement tests, brain imaging at the start and end of the study, and provide blood and urine samples once a year to measure dye levels in your body. The control group (people not receiving contrast dye) will undergo similar testing and imaging, but without the dye injections. The entire study lasts 5 years.

AI-generated summary from trial data · Jun 4, 2026 · Not medical advice

Safety of repeated contrast dye use in brain imaging over five years

What is this trial?

Do you qualify?

What participation looks like

Trial locations(51 sites)