What Is Magnetic Resonance Enterography?
Magnetic resonance enterography is an imaging test used by specialists in the diagnostic process of diseases that affect the small intestine. The test relies on magnetic fields to create detailed images and, as Johns Hopkins Medicine reminds us, it doesn’t involve any radiation. Today, we’ll answer your questions.
What is magnetic resonance enterography used for?
As we have already indicated, the test is particularly useful for obtaining detailed images of the small intestine. With their help the doctor can find the following:
- Tears in the wall of the intestine (even these are small).
- Irritated or inflamed areas.
- Blockages or obstructions of the intestinal canal.
- Ulcers or pus-filled pockets on the lining.
- Bleeding somewhere in the small intestine.
These five elements are useful to determine the presence of any disease. For example, studies and research support its use to detect Crohn’s disease. In turn, evidence indicates that it can be used to rule out ulcerative colitis.
The use of other imaging tests may not be sufficient to detect both conditions, so more accurate diagnoses can be made with their help without resorting to invasive procedures. But MRI enterography isn’t used only for diagnosis, it can also be used for the following:
- Keeping track of the disease.
- Assessing how well the body is responding to treatment.
- Monitoring for possible complications that don’t produce obvious symptoms.
Regarding the latter, magnetic resonance enterography can detect small tumors with great precision. Because x-rays aren’t required, it’s a process that prevents ionizing accumulation in the patient.
What are the risks of MRI enterography?
Like other tests of its kind, MRI enterography carries a number of risks for patients. The most important are described below:
- The magnetic field generated can disrupt the operation of some instruments implanted in patients (pacemakers, ear implants, defibrillators, brain aneurysm clips, and so on).
- Contrast material can cause allergic reactions in some people.
- In patients with liver deficiency, the contrast medium can cause organ problems.
Although the evidence doesn’t seem to show complications, its use is generally avoided in pregnant women. This happens in principle in pregnant women who are less than three months pregnant, as there aren’t enough studies that account for risks or sequelae.
How should you prepare for the test?
If your doctor has suggested that you have this test, there are several things you should consider. In principle, if you fall into any of the above categories, you should discuss this with them urgently.
Evaluate the pros and cons of taking the test and discuss the possible alternatives available. Since the test takes an average of 45 minutes, some patients may experience anxiety or claustrophobia. Therefore, you should also discuss the possibility of sedation to avoid potential problems. Other things to keep in mind are the following:
- Get a general blood test to assess your health.
- Ask the specialist if you need to temporarily abandon any drug treatment that you follow.
- Consider using earplugs if your hearing is very sensitive.
- Don’t wear jewelry, piercings, or other items on the day of the test.
- Avoid eating or drinking six hours before the test.
- Someone should accompany you in case you’re discharged the same day (which happens in most cases).
You should also talk to a specialist if you are prone to allergies. Although the chances are very low, the contrast used can cause a reaction in some patients. The doctor will choose to do a small test to determine your body’s response.
In addition, we recommend that you talk with the specialist about the real reasons why the magnetic resonance enterography will be performed. You must be aware of what they’re looking for and the possible diseases or damage they may find.
What can you expect during an MRI enterography?
On average, the duration of an MRI enterography is 45 minutes. You won’t feel any type of pain, although you may feel uncomfortable from being immobile for so long or from the noises of the machine. It’s very important that you limit your movements, otherwise the images will lose precision. The procedure, in general, consists of the following:
- The doctor will administer a sedative to avoid claustrophobia (if you so wish).
- Your clothing will be replaced with a robe for added comfort.
- You will be given a contrast material orally. This is usually given an hour before the test begins.
- The staff will help you lie down on the machine table.
- They’ll inject you with supplemental contrast material through an IV.
- They’ll warn you about limiting your movement before they start the test.
- Then, they’ll activate the machine and it will begin to scan your body. You may be asked to hold your breath at some points.
- After obtaining the images, they’ll be evaluated and, if necessary, they’ll be complemented with other scans.
At the end of the test, you’ll get dressed and the nurses will direct you to the recovery room if you have been sedated. The contrast material may make you dizzy, leave a bad taste in your mouth, or give you minor cramps or nausea.
There are no dietary limitations after MRI enterography is performed. Unless the specialist suggests otherwise, plan your routine normally. The results may be available on the same day, or, if not, the medical center will advise you.
When you have them, share them with the specialist and he will assess the findings. They may suggest carrying out a couple more tests for extra images, if there are still doubts regarding what the images reflect. Whatever the case, this depends on the reasons that led to the examination in the first place.
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