Magnetic Resonance Angiogram (MRA)
What is magnetic resonance angiogram (MRA)?
Magnetic resonance angiogram (MRA) is a minimally invasive method of recording the structure and function of the blood vessels of the body with the use of non-ionizing electromagnetic radiation.
How does MRA work?
The MRA machine uses radiofrequency (rf) radiation in the presence of carefully controlled magnetic fields to produce high quality cross-sectional images of the blood vessels in any plane. It gives a more accurate picture of the blood vessels and is sometimes preferred over other techniques of imaging. 1
When is MRA advised?
In the recent years, with the advent in the scanning techniques and the improvement in the associated materials MRA is being advised for detecting a wide array of disorders of the blood vessels. The applications of MRA include:
- To detect various disorders of the blood vessels that supply specific organs such as the heart, brain, kidneys, etc.
- To evaluate the condition of the blood vessels of the legs in conditions such as narrowing of the vessels
- To detect injuries to the blood vessels in cases of trauma or accidents
- Assess the conditions of the blood vessels before planning any surgeries 2, 3
What is the preparation required for MRA?
There are certain precautions which need to be taken before undergoing MRA as the procedure involves exposure to high intensity magnetic field. One should not have any metal and electronic objects (such as jewellery, watches, pins, credit cards, etc.,) with him while undergoing the scan. Individuals with pacemakers, ear implants and clips placed within certain blood vessels should not undergo this procedure as it affects the functioning of these. An individual should always inform the doctor if he has undergone any such treatments or is suffering from any other disorder/condition.
The individual undergoing the scan may be asked to wear a gown and the procedure generally lasts for about 15-30 minutes depending on the type of scan required. If a dye is required then it may be injected through a vein or given as a drink. The individual is required to lie on the table which moves gradually into the scanning machine and the individual should lie still until the scanning is completed. 2
What are the complications of MRA?
In most of the cases MRA scanning is not associated with any adverse effects. In cases where a dye is used it may cause allergic reactions in some of the individuals.
1.Wilkinson ID, Paley MNJ. Magnetic Resonance Imaging: Basic Principles. In: Adam A, Dixon AK (editors). Grainger & Allison's Diagnostic Radiology. 5th ed. Philadelphia: Churchill Livingstone; 2008.
2.Radiologyinfo. MR Angiography (MRA). [homepage on the internet]. Oak Brook, IL: Radiological Society of North America, Inc.; c 2008. [updated 2007 Jul 03; cited 2008 Jun 06]. Available from: http://www.radiologyinfo.org/en/info.cfm?PG=angiomr
3.Graves, MJ. Magnetic resonance angiography. The Bri Jou Rad. 1997; 70: 6-28.
Date last updated: April 18, 2015