Related Experiment Videos
Peripheral MR angiography
K Y Ho1, T Leiner, M W de Haan
1Department of Radiology, University Hospital Maastricht (AZM), P. O. Box 5800, 6202 AZ Maastricht, The Netherlands.
Insights
Non-invasive MR angiography offers a promising alternative to X-ray angiography for diagnosing peripheral atherosclerosis. Contrast-enhanced MR angiography significantly improves image quality and provides detailed vascular data, potentially rivaling traditional methods.
Area of Science:
- Vascular imaging
- Medical diagnostics
- Radiology
Background:
- Peripheral atherosclerosis is a debilitating condition requiring accurate diagnosis.
- X-ray angiography is the gold standard but is invasive and uses contrast agents.
- Non-invasive Magnetic Resonance (MR) angiography is explored as an alternative.
Purpose of the Study:
- To explain the working mechanisms of time-of-flight (TOF) MR angiography.
- To explain the working mechanisms of contrast-enhanced (CE) MR angiography.
- To discuss the clinical usefulness of both TOF and CE MR angiography for diagnosing peripheral atherosclerosis.
Main Methods:
- Discussion of time-of-flight MR angiography principles and limitations.
- Explanation of contrast-enhanced MR angiography using gadolinium chelates.
- Comparison of MR angiography techniques with X-ray angiography.
Main Results:
- Time-of-flight MR angiography is limited by flow-related artifacts.
- Contrast-enhanced MR angiography significantly improves image quality.
- CE-MRA provides high-resolution 3D data of the peripheral vascular tree rapidly.
Conclusions:
- CE-MRA is a potentially powerful, non-invasive diagnostic tool for peripheral atherosclerosis.
- MR angiography, particularly CE-MRA, may become a clinical competitor to X-ray angiography.
- Further evaluation of MR angiography in clinical work-up is warranted.
Abstract:
Atherosclerotic disease of the lower extremities is a common disorder in western society. Its debilitating nature calls for accurate diagnosis and treatment. The gold standard for diagnosing this disease by depiction of vessel morphology is X-ray angiography (either conventional or digital subtraction angiography). However, the invasive nature of this technique and the possible harmful effects of iodinated contrast agents have led to the idea that non-invasive MR angiography might be a good alternative for acquiring information about vessel morphology. Most extensively studied was time-of-flight MR angiography. Although first results with this technique were encouraging, it is now apparent that time-of-flight MR angiography is hampered by the virtue of which it exists, since blood flow not only generates vessel-to-background contrast, but is also the cause of disturbing artifacts. However, with the introduction of minimally invasive contrast-enhanced MR angiography, using gadolinium chelates to reduce the T1 of blood, image quality has improved dramatically. Moreover, using contrast-enhanced MR angiography, high-resolution three-dimensional data about the entire peripheral vascular tree can be obtained within several minutes, which might make MR angiography a true competitor of X-ray angiography as a diagnostic tool in the clinical work-up of a patient with complaints of peripheral atherosclerosis. The purpose of this article is to explain working mechanisms and usefulness of both time-of-flight and contrast-enhanced MR angiography.