1.5 Tesla MRI

What is MRI?

Magnetic resonance imaging (MRI) uses a large magnet and radio waves to look at organs and structures inside your body. Health care professionals use MRI scans to diagnose a variety of conditions, from torn ligaments to tumors. MRIs are very useful for examining the brain and spinal cord. The biggest advantage that an MRI Scan has — over, say, the CT Scan or Tomography Scan — is that it produces 3D images instead of 2D images, though 3D reconstruction is now available for CT scans too. The extra "vision" and "understanding" this additional dimension of depth offers is invaluable for medical purposes, be it diagnosis or treatment. This makes an MRI Scan highly effective, and unmatched, when it comes to analyzing small structures of the brain, such as the brain stem or the pituitary gland. An MRI Scan usually doesn't have any risks associated with it.

Unlike CT scans and X-rays, the MRI scan procedure is safe and radiation-free, meaning it is safe even for pediatric and repetitive studies. The advantages of MR imaging are:

• • Radiation-free imaging.
• • Multi-sequence detail — one of the most comprehensive and advanced imaging methods, incorporating several complex imaging sequences to best adapt to your complaint.
• • Soft-tissue demarcation — much better than CT scans and X-rays.
• • No significant side-effects of magnetic imaging.

What is an MRI scan with contrast?

While an MRI scan will generate clear images of dense organs and structures, substances with a low density can turn out hazy and hard to detect. To make the latter more clearly visible, the patient may be administered a special dye — technically referred to as a "contrast material" — via injection (done to make the liver, gall bladder, urinary tract or blood vessels stand out sharper in the scan results), orally (to enhance images of the digestive tract), or via enema (when greater clarity is required for the intestines). To help the kidneys remove the contrast material after the procedure, you may be advised to drink plenty of fluids.

Common uses of MRI scan

MR imaging of the body is performed to evaluate:

Common MRI examinations

MRI can image almost any part of the body — these are the scans performed most often.

MRI scan preparation

Very little preparation is required prior to an MRI scan. You will be asked to wear a gown. As magnets are used in the scanner, no metal objects must be present — the doctor will ask you to remove all metal jewellery and accessories that could interfere with the scan. Individuals cannot go for an MRI if they have metal objects inside their body, such as bullets, shrapnel, cochlear implants or pacemakers. Some MRI scans use an injection of contrast liquid (gadolinium) to improve visibility of specific tissue relevant to the scan. You must inform the technologists if you are claustrophobic — in such cases, a mild sedative may be recommended before the scan. Women should always tell their doctor and technologist if they are pregnant or planning to become pregnant, as there might be a risk of harm to the fetus.

• • Inform staff about implants, pacemakers or medical devices.
• • Remove all metallic objects, jewellery and cards.
• • Carry previous reports, films and your prescription.
• • Follow fasting instructions if advised.
• • Inform staff if you are or may be pregnant.
• • Arrive 15–20 minutes before your appointment.

MRI scan procedure

As soon as the patient enters the MRI scanning room, the technician or doctor will ask you to lie on the table. An MRI scanner is a short cylinder open from both sides — you enter either from the head or the feet, depending on the part being scanned. A computer operates the scanner from a separate room to keep it away from the magnetic field, and the radiologist communicates with you via an intercom to guide you and keep you comfortable. Sometimes a contrast material — gadolinium or iodine — is used intravenously, with more images captured during or after the injection. Once the scan is complete, you may be asked to wait while the radiologist checks whether more images are needed, and the technologist will remove your IV line. The entire procedure may take 30–60 minutes.

1. Registration

   Check in with your prescription and ID.

2. Safety screening

   A short form about implants, metal and medical history.

3. Preparation

   Change into a gown and remove metal items.

4. MRI scan

   Lie still on the table while images are taken.

5. Image review

   A radiologist reviews your images.

6. Reporting

   Your report is prepared and shared once ready.

Time taken for MRI scan reports

After the scan is complete, the computer generates images of the areas examined, which can be transferred to a hard copy (film). The radiologist interprets these images in the form of a report. An MRI procedure itself lasts 15 to 90 minutes depending on the body part being scanned and the number of images taken. MRI reports will be available within 24–48 hours of the procedure in most cases.

Benefits of MRI scan

• • A noninvasive and painless imaging technique that does not involve exposure to radiation.
• • Images of soft-tissue structures — such as the heart, liver and many other organs — that are more accurately characterised than by other imaging methods.
• • A valuable tool in diagnosing a broad range of conditions, including cancer, heart disease, and muscular and bone abnormalities.
• • Allows physicians to assess the biliary system noninvasively and without contrast injection.
• • A noninvasive alternative to X-ray, angiography and CT for diagnosing problems of the heart, blood vessels and other body parts.
• • Can detect deformities that might be unclear on bone with other imaging methods.

Appointments, duration & waiting

MRI scans at Deewan Diagnostics are offered on a first-come-first-served basis. Because the factors below can change from one study to the next, getting an MRI scan often involves a waiting time — the exact length of your procedure, and that of the patients before you, depends on each patient's condition and cooperation.

If your question is how long an MRI should take, note that several factors together determine the time required:

• • Procedure — time varies by study: a routine MRI brain is typically completed in under 15 minutes, while a multiparametric prostate MRI with contrast may need over 60 minutes of planning and sequences.
• • Patient movement — if a patient is unable to lie still and moves during the procedure, partial sequences may need to be restarted, which can extend a 15-minute scan to 40 minutes or more.
• • Patient-specific detailing — when findings require additional detail, the technician may spend a few extra minutes to better help doctors assess the case.

MRI questions, answered