If you have ever been injured, you might have received an MRI or CT scan. Both are types of diagnostic imaging tests used to help doctors form a diagnosis. A doctor might choose one over the other based on the area being scanned, the patient's health history or the urgency of the images. Essentially, both machines take pictures of your body's inside (bones, organs, soft tissue, etc.) in a non-invasive manner. Though they both have their pros and cons, there are several differences between an MRI and a CT scan.
An MRI, or magnetic resonance imaging, uses powerful magnetic fields and radio frequency waves to produce a detailed image of your body's insides. An MRI can look at the organs, soft tissues, bones, ligaments, joints, blood vessels and tendons in the head, heart, abdomen, cervix, chest, pelvis, spine and muscles. MRIs are used to detect tumors, cysts, aneurysms and other medical conditions. It can also be used to try and detect cancer, though it is not a definitive tool; MRIs are mostly used to find the best site to do a biopsy.
Unlike a CT scan, which uses radiation, an MRI does not. The patient lies down inside the MRI machine, which then creates a magnetic field before sending radio frequency waves into the body.
By creating a magnetic field, some hydrogen atoms inside the body line up while others keep spinning. The radio frequency waves make these atoms spin in the opposite direction. Once the radio waves stop, the atoms return to their normal position but emit energy. The energy sends signals to a scanner. A computer then uses mathematical formulas to produce the images.
An MRI can take anywhere from 15 minutes to an hour, depending on several factors like the location of the area being scanned. Therefore, MRIs are not usually ordered when the image is needed immediately.
Another reason MRIs are not used as much is that the patient must lie completely still during the procedure. Some patients can get claustrophobic inside the machine, though there are some open MRI machines. MRIs can also be extremely noisy; some patients have to wear headphones or earplugs.
To better see the body's inside, an MRI might require a patient to take a contrast dye; the dye outlines the structures and creates a clearer image. Please note that some people might be allergic to the dye.
Typically, MRIs are also more expensive than CT scans; they are about twice the cost.
Since MRIs rely on magnetic fields and radio frequency waves, some people can't use the machine, including anyone with:
If you have any of these items or are pregnant, speak with your doctor before using an MRI machine.
A CT scan, or computerized tomography, can sometimes be called a CAT scan, or computerized axial tomography. This more common machine looks at trauma, fractures, tumors, internal bleeding, dislocations, infections, aneurysms and cysts in the head, chest, abdomen, spine, pelvis, hips, bladder and gastrointestinal tract, as well as bones, soft tissues and blood vessels. Like MRIs, CT scans can also be used to try and detect cancer, though it is not a definitive tool; they are mostly used to find the best site to do a biopsy.
For a CT scan, the patient lies down on a table, which slides through a scanning ring. The scanner rotates around the patients and uses x-rays to produce a series of images, or “slices,” taken at different angles. These “slices” are then sent to a computer, which creates a 3D image. In the image, dense objects (bones and teeth) appear white while less-dense objects (organs, muscles, etc.) appear gray.
Please note that since CT scans use x-rays, the patient is exposed to a small dose of ionizing radiation.
CT scans are typically much cheaper and faster than MRIs. CT scans take between five to 10 minutes, and they are about half the cost of an MRI.
Like MRIs, a CT scan might require a patient to take a contrast dye; the dye outlines the structures and creates a clearer image. Please note that some people might be allergic to the dye.
Typically, the other people who should be concerned with using a CT scan are pregnant women, as there is a small dose of ionizing radiation.
Please note that since CT scans use x-rays, the patient is exposed to a small dose of ionizing radiation. Avoid getting multiple CT scans so you don't damage your DNA.
At Sherman Oaks TMJ expert, Dr. Eddie Siman, we have our own in-house CT scan and radiographic evaluation, making us one of the few offices to have an in-house volumetric cone-beam CT scanner.
Dr. Siman uses the CT scanner to analyze every aspect of your skull, bones and joints, including their structures and how they relate to one another. He also measures your back and neck muscles to see how your TMJ-related issues are affecting your posture and upper-body pains.
The in-house CT scan helps Dr. Siman diagnose TMJ disorder and see the degree of wear and tear in the face.
By having our own in-house CT scan, we can scan a patient the same day they come to our office instead of sending them to a radiologist for a CT scan. This saves the patient time and money.
Dr. Eddie Siman has over 35 years of experience and is a premier TMJ and Sleep Apnea expert in Los Angeles and Orange County. Many come to Dr. Eddie Siman with severe tinnitus, migraine problems, and sleep apnea with no relief in sight. Little do these patients know that their painful symptoms are tied to the Temporomandibular joint (TMJ). Think outside the box and pay a simple visit to Dr. Siman today so you can finally find the source of all your pain and get rid of it once and for all.
14629 Ventura Blvd, Sherman Oaks, CA 91423
414 N. Camden Drive Suite #1240, Beverly Hills, CA 90403