Do mri scans require fasting?

The article is consulted professionally by Master, Dr. Nguyen Thanh Nam – Imaging Doctor – Department of Radio diagnostics – Share99 Da Nang International Health Hub.

Mri is a significant step forward in the medical imaging industry. This effective, safe and accurate diagnostic method is now the top priority of specialists to prescribe to patients in complex conditions. In order for mri scans to give the most accurate, clear images, patients need to have certain preparations.

1. Is mri necessary?

The mri technique uses a strong field (Bo) and a radio frequency pulse system to control the electrolytic activity of the hydrogen atomic nuclear. Here, the hydrogen atomic ion ion (which is much in the water of body tissue) under the action of radio waves and the Bo field has radiation of energy in the form of signals with radio frequencies. These signals will be received and processed by the machine system to generate image-shaped data.

The outstanding advantage of MRI is that it does not use radiation, does not cause radiation, so it is very safe for patients, the next-generation MRI scanner does not make noise, so it feels comfortable and comfortable. In addition, MRI diagnostic imaging has a good resolution, multi-pulse, multi-plane, 3D renewable,… applicable to most body parts

Currently, with the above advantages, mri is widely used in early detection, diagnosis and monitoring of many body diseases such as: spinal neuropathies; cerebral palsy, meselecular pathology, tumors of abdominal organs such as liver, bile tract, kidneys, aphthium, pancreas, gastrointestinal tract, ovarian uterus; breast cancer; cardiovascular diseases (cardiovascular resonance, blood vessels), congenital fetal abnormalities (fetal MRI), tumor screening, body maculation …

Mri scans are painless, and the shooting lasts about 12-45 minutes. Your doctor can then read the correct results and give you your current condition or health, thereby having the right treatment and advice.

2. Do mri scans require fasting?

In general, the majority of patients with MRI resonance imaging do not have to fast.

MRI scan

Most cases of Non-Fasting Mri

However, patients need fasting in the following cases:

  • When anesthesia is required, fasting must be taken 4-6 hours before shooting
  • When taking a hepatic examination to assess the pathology, fasting is about 4-6 hours.
  • When it is necessary to inject anti-optical drugs from fasting needs before 4-6h

3. Some things to know when preparing for an MRI scan

When you conduct an MRI scan, you will lie inside a large magnet tube, which will create a very strong magnet field. Therefore, you only perform this method of imaging when prescribed by a doctor. When shooting, you lie still, without movement waiting for the camera to work to get the best quality and effective diagnostic imaging.

Before the scan and when diagnosing the disease, you should bring the results of tests, ultrasound, X-rays and CT (if any) for your doctor to consult, make appropriate imaging techniques for each pathology.

When the room staff receives you into the shooting room, you will be instructed to complete the procedure of res resonance safety, hospital dressing, removing items such as dentures, jewelry such as rings, necklaces, earrings, watches, credit cards, ATM cards, keys from …

MRI scan

Patients should remove items from, metal before an MRI scan

In addition, technical staff also use specialized tools to check for foreign objects and metal equipment placed in the body. If there are small metallic foreign objects, located in the muscles with loose tissue such as the brain, eyes, lungs, heart, next to large blood vessels … mri should not be taken. In other locations, it is possible to shoot.

You need to inform the technical staff if you have any tools or equipment such as: Artificial heart valves, vascular stents, contraceptive rings, Defibrillators, Artificial Pacemakers, Hearing Aids, Automatic drug pumps …

In case of needing a contrast injection, the medical staff will ask about the history of drug allergies, possible allergy symptoms after injection such as: Nausea, rash … Anti-optical drugs are rarely toxic to the body. If you have a hepatic or anesthesia scan, you should ensure hunger 4-6 hours before the scan.

Usually the duration of an MRI scan varies from 10 minutes to 45 minutes depending on the agency to be surveyed, the cooperation of the patient (lying still) and the patient is given a contrast injection or not. In the shooting room, the technician will carefully guide the patient on the shooting table with the most suitable position so that you can lie still during the shoot.

When shooting, the patient will hear noise from the machine due to the resonance of the word, which is normal. You may be wearing music headphones to reduce noise.

Depending on the body part taken, the technician may request other requirements such as: Do not swallow saliva when shooting the cervical spine, require holding your breath for a short period of time when shooting the abdomen and chest to get a better image.

MRI scan

MRI scan may require contrast injections

In case of need for an anti-optical injection, the drug will be injected into a vein in the forearm or wrist area, the injection time can be from 1 to 2 minutes. After the injection, the part to be taken will be further surveyed to assess the level of drug infiltrate of the lesion

When injecting the drug, the person may feel the whole body warm or have a bitter taste in the tongue, which is normal, the symptoms will clear themselves within 2-5 minutes. Films and results after MRI scans will be available as early as 15 to 30 minutes, if standard assembly is required, the waiting time may be about a few hours longer.

Thus, most mri resonance imaging cases patients do not need fasting, unless an anti-photoretrosive injection, anesthesia or hepatic bile scan is required. If you have questions about issues before and during an MRI scan, directly ask your doctor and technical staff.

Currently, Share99 International Health Hub has introduced a 3.0 Tesla silent technology to help diagnose the disease more accurately and help you feel more comfortable when shooting.

  • Silent technology is especially beneficial for patients who are children, the elderly, people in poor health and patients undergoing surgery
  • Limit noise, create comfort and reduce stress for customers during shooting, making recording better quality and shortening shooting time.


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About: John Smith

b1ffdb54307529964874ff53a5c5de33?s=90&r=gI am the author of I had been working in Vinmec International General Hospital for over 10 years. I dedicate my passion on every post in this site.


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