|
|
|
|
Magnetic resonance angiography is a relatively new investigation for arterial disease. Unlike CT scanning, this procedure does not rely on radiation. Instead, the patient is subjected to very strong magnetic pulses. These pulses cause transient alteration in the hydrogen atoms polarity in the part scanned. On switching the magnetic field off, the atoms retain their natural polarity and on doing this, they release a very small amount of energy. The machine is able to pick this energy up, analyse it and present it in a very high quality graphic format. A contrast is sometimes given to enhance the appearance of certain tissues. Magnetic resonance angiography always involves the administration of this contrast. A venous line will therefore be established prior to the procedure.
The MRI machine is usually housed in a special room. Due to the very strong magnetic field generated by the scanner, metal objects are not allowed in the room. Patients are advised to leave any metal objects, particularly watches, keys, etc, outside the room. The duration of the procedure will vary according to the part scanned.
There are no specific precautions to take following this investigation. All venous lines will be taken out as the patient is made ready for discharge.
Whilst the procedure itself has no known complications, certain precautions and conditions will have to be met prior to scanning. Patients with large metal implants such as pacemakers, major joints, etc, are not suitable for this investigation. Patients with small metal implants in critical areas such as brain aneurysm clips or eye metal foreign bodies and also not suitable. Claustrophobic patients may find it very difficult to tolerate the investigation, particularly that the machine emits very loud "banging" noise during scanning.
Admission: Day of Procedure Anaesthetic: Not required Stay in hospital: Two to three hours Time off work: Three to four hours First follow-up appointment: 2 weeks |
|
