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MRI Brain Scans Explained

Magnetic resonance imaging or MRI of the brain is a non-invasive and painless procedure. It is an exam or scan that produce detailed images of a person’s brain and brain stem. The machine creates images through a magnetic field that uses radio waves. The patient goes to the hospital, clinic, or radiology to undergo a brain MRI.

A brain MRI is different from an X-ray or a CT scan because it does not use any radiation to create images. It is an advanced method that combines images to produce a three-dimensional (3D) image of the brain’s internal structures.

That’s why it is more effective and reliable than other scanning methods when it comes to detecting abnormalities in the brain. Sometimes, a health professional gives a dye or contrast agent intravenously so that the machine produces clearer images. That way, the doctor visualize the brain structures and abnormalities clearly. Read on!

The Importance of Brain MRI Scans

A brain MRI is an advanced and useful tool used by health professionals to detect a wide range of neurological conditions. These include multiple sclerosis, aneurysms, spinal cord injuries, stroke, and hydrocephalus.

The MRI scans are also helpful in identifying infections, inflammation, cysts, tumors, and hormonal disorders, including acromegaly and crushing’s syndrome. The method can also be used for detecting brain hemorrhage, swelling, and developmental problems like Chiari malformation.

Likewise, a health professional uses the MRI machine to detect blood vessel issues in the brain and problems associated with any previous head injury. A brain MRI scan is also helpful in determining damages from head injury and stroke.

Most often, health professionals perform this type of examination to determine symptoms like seizures, weakness, dizziness, and changes in cognition, behavior, headaches, spinal cord pain, and blurry vision.

All these symptoms are due to a brain issue, and an MRI scan can help the professional detect them easily. Besides, a functional MRI or fMRI of the brain can help surgeons assess the brain structure and function. It is an advanced method that pinpoints brain areas responsible for cognition, body movement, speech, and language.

FMRI measures metabolic changes in the brain when a person performs certain tasks. During the examination, a doctor may ask the patient to perform smaller tasks. Most often, it includes answering a few questions or the patient tapping his or her thumb with the fingertips. Magnetic resonance angiography or MRA is another type of MRI used to take images of the brain’s blood vessels.

What is involved in Brain MRI?

Magnetic resonance imaging is an advanced scanning technique used to detect a wide range of conditions, including brain abnormalities and disorders. The procedure requires the health staff to ask the patient if he or she has any mental in the body. For instance, these are inner ear implants, vascular stents, artificial joints, pacemaker, defibrillator, and brain aneurysm clips.

The doctor may also ask the patient if he or she has worked with sheet metal or get injuries from metal shrapnel. Remember, these questions are important, and health professionals ask some questions from their patients before they take the MRI exam. All these things affect the safety of brain MRI procedure.

If there are any pacemakers or implants, they can get malfunctioned due to the powerful magnetic field in the MRI machine. So, if a person is wearing anything like sunglasses or jewelry that contains metal, it is crucial to remove those items. Metal interferes with the machine magnetic field and deteriorates its ability to produce clearer images.

Although dental fillings and braces do not cause a problem, it is essential to remove items like pins, pens, pocketknives, keychains, etc. The medical staff may ask the patient to wear clothing or gown that does not contain any metal fasteners. If the patient has a smartphone, watch, or any other electronic device, it will be removed before the procedure.

Moreover, a pregnant woman should immediately inform the health provider before undergoing the brain MRI exam. The magnetic field can affect the fetus and interfere with the proper development and growth of the unborn baby. A patient must also inform the medical staff if he or she has claustrophobia.

If this is the case, the doctor will give sedatives to the patient during the procedure. Another option for the patient is to undergo an open MRI scan. An open MRI machine has a wide tunnel that can help the patient cope with claustrophobia.

The Procedure

Experts recommend people to stay still during the exam so that the machine can take clearer images. Most often, children have difficulty staying still during the exam. That’s why the medical staff give them sedatives orally or intravenously.

Sedation is also helpful for people who have claustrophobia. The procedure starts when the patient lies down on the exam table, which slides into the machine. The table slides through a tube that has a magnet shape. Sometimes, the staff places a plastic coil around the patient’s head.

Moreover, when the table slides into the MRI machine, the staff will start taking images of his or her brain. Each image takes a few minutes, and there is a microphone in the MRI machine that allows the patient to communicate with the medical staff.

How Long Does It Take?

The brain MRI scan usually takes 30 to 60 minutes. The doctor will give a contrast solution, such as the gadolinium intravenously, to allow the machine to see some parts of the brain clearly. The contrast solution or agent helps determine the brain’s blood vessels. Because an MRI scan is a non-invasive and harmless procedure, the 60 minutes won’t bother the patient.

On the other hand, if the patient feels uneasy due to the loud and strange noises, the staff will provide him or her with earplugs. These plugs can block the noises coming from the machine. Likewise, the patient can also listen to music to spend 30 or 60 minutes comfortably.

How Much Does It Cost?

A brain MRI is a sophisticated procedure used to detect different brain abnormalities and conditions. The machine uses a strong magnetic field and radio waves to capture images, which are then processed and stored on a computer. The MRI machine is used to capture detailed images of the brain, its internal structures, and surrounding nerve tissues.

When it comes to the cost of brain MRI, it can cost something between $1,000 and $5,000 depending on the location, hospital, disorder, and duration. The procedure is performed in a doctor’s office, clinic, or hospital. For instance, in the U.S, the scan typically costs between $2,770 and $5,500. The cost varies from state to state and country to country.

In some hospitals, a brain MRI scan without a contrast solution or agent can cost around $4,000. The MRI scan, when deemed necessary, is usually covered by the patient’s health insurance plans. If the patient meets deductibles, the insurance company will allow for a copay for the MRI scan.

Research shows that every 1 in 20 patients that undergo MRI feels claustrophobic inside the machine. That’s why the doctor gives him or her a mild sedative. If the sedative is Diprivan, it would cost the patient something between $125 and $400. Again, this depends on where the patient undergoes the scan.

An estimated 10% of patients require an intravenous injection that contains a contrast solution. The purpose of this special solution, dye, or agent is to allow the MRI machine to capture clearer images of certain parts of the brain. In that cause, the solution can cost $100-$300.

What Do Brain Tumors Looks Like in an MRI Scan?

MRI machines use a powerful magnetic field, radio waves, and a high-end computer to generate detailed images on internal organs and tissues. It can also produce high-quality images of brain infections, cysts, and tumors. The machine has high sensitivity when it comes to detecting tumors and evaluating the surrounding tissues.

So, how does a brain tumor look like on MRI? Well, there are different types of tumors and each one look different on an MRI image. For instance, a high-grade glioma like glioblastoma multiforme has a distinctive appearance than a benign or low-grade glioma. On an MRI scan, the center of the tumor appears as dead cells surrounded by a rim of swelling, inflammation, or edema.

Glioblastoma grows quickly and outgrows the blood supply, which causes the center to become necrotic. On the other hand, a low-grade glioma is seen as a dark area or low-density areas on the scan. High-grade gliomas show more contrast with white on the outside and their necrosis looks black on the MRI scan.

Malignant Astrocytomas

These are hypo-intense on T1-weighted images from the MRI scan. Malignant Astrocytomas enhance heterogeneously following contrast infusion. These areas have solid contrast within the serpiginous pattern. A health professional may also see it as a totally solid pattern of enhancement on the MRI scan.

These tumors enhance in a ring-like shape or pattern with think appearance and have tiny finger-like projections on the MRI scan. These projections run toward the necrotic center of the tumor that can be clearly seen in the MRI image.


MRI scans can be used to detect chordoma, a benign brain tumor. The tumor and its surrounding structures show an excellent contrast on the MRI image. These are lobulated tumors with low to medium signal intensity on the T1-weighted MRI images. Likewise, these tumors have high signal intensity on T2 weighted MRI images.


These benign tumors appear as Dural-based masses to grey matter on T1-weighted and T2-weighted images. Meningiomas enhance excellently on MRI after contrast administration. Sometimes, the tumors have areas of central necrosis that may not enhance on the MRI image.


These are malignant tumors that have a macroscopic appearance on the MRI image. Ependymomas are well-defined lobulated grey tumors with a moderately cellular appearance on the MRI. Sometimes, they also appear in frond-like and tan-colored tumors. MRI scans also show focal areas of Ependymomas calcification.


It is another malignant brain tumor that has pronounced heterogeneous features on MRI. The tumor is present with different T1 and T2 intensities on the MRI with enhanced patterns. The image also shows the formation of cysts, hemorrhage areas, calcification areas, and leptomeningeal seeding.

Final Words

Brain MRI is an advanced imaging technique used to detect a wide range of conditions, including tumors, cysts, swelling, bleeding, as well as structural and developmental abnormalities. The technique is also used to determine infections and inflammatory-related brain conditions. It is a non-invasive and safe diagnostic method because it does not involve the use of radiation.

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