Improving the Concentration of MR Contrast in the Arteries

Summary

In Contrast-Enhanced Magnetic Resonance Angiography (CE-MRA) a contrast agent is injected into an arm vein using a programmable medical device called a power injector. Once the contrast has circulated to the blood vessel of interest they can be imaged with MRI and distinctly separated from surrounding non-vascular tissue.

This project is designed to find the best way to administer the contrast agent during CE-MRA to produce the best images. The clinical availability of programmable power injectors facilitates the use of variable contrast rate and volume injection protocols that are based on patient specific parameters.

CE-MRA is a valuable imaging tool for diagnosing abnormalities of the major blood vessels in the chest and abdomen. It is often used in conjunction with cardiac magnetic resonance (CMR) examinations to evaluate the blood vessels of the heart and lung. CE-MRA is attractive because 1) it does not involve radiation, and 2) the contrast agents used are not toxic to the kidneys and can be used in patients who are at greater risk for kidney dysfunction following iodinated contrast agents.

We plan to administer a small (1cc) test amount of contrast, taking pictures as the contrast passes through the blood vessels, and analyze the results. Using this information, we will administer an individually patient-tailored injection given in multiple phases (i.e., a "multi-phasic" injection) to maintain constant contrast concentration (and therefore constant signal intensity) throughout the scan. We believe this will reduce image blurring, and improve the sharpness and likely the diagnostic quality of CE-MRA.

Conditions

• Magnetic Resonance Angiography
• Contrast Media

Interventions

OTHER

Standard Injection Rate

Normally an IV is placed in an arm and the gadolinium contrast (30-40 cc, depending on patient size) is administered through the IV with a power injector as a single bolus. Subjects will have a test bolus and main bolus.

OTHER

Patient Tailored Injection Rate

Normally an IV is placed in an arm and the gadolinium contrast (30-40 cc, depending on patient size) is administered through the IV with a power injector as a single bolus. Subjects will have a test bolus and main bolus. We will use a mathematical algorithm to rapidly analyze the test bolus and calculate a predicted "best" way to inject the main bolus - likely slower and "multi-phasic", meaning different flow rates as the bolus injection evolves.

OTHER

gadolinium contrast

Sponsors & Collaborators

• University of Washington

  lead OTHER

Principal Investigators

• Jeffrey H. Maki, MD, PhD · University of Washington

Study Design

Allocation

RANDOMIZED

Purpose

DIAGNOSTIC

Masking

NONE

Model

PARALLEL

Eligibility

Min Age

18 Years

Sex

ALL

Healthy Volunteers

No

Timeline & Regulatory

Start

2014-06-30

Primary Completion

2015-10-31

Completion

2015-11-30

Countries

• United States

Study Locations