Pictures from both open and closed MRI machines can show doctors detailed images of many organs and structures inside the body, such as the brain, the heart, the liver, ligaments and tendons, and blood vessels, according to WebMD. It can also show the bones and joints. Although they are both used for the same purpose, the image quality and precision of open MRIs are not always as good as those from closed MRIs, according to Stony Brook Medicine.
MRI scans can be used to search for many different internal problems, such as tumors, blood vessel diseases, bleeding, infection and injury, according to WebMD. For example, MRI images of the head can help doctors analyze damage from a stroke, optical or auditory nerve injury, brain tumors and bleeding on the brain.
When used on the heart, MRI images can reveal details about the heart, coronary blood vessels, and the valves inside the heart, notes Stony Brook Medicine. MRIs can also help determine whether a bone is broken, if it is not certain based on the X-ray films. MRI scans provide better contrast than computed tomography scans, without using radiation as the CT scans do. As a result, MRI is useful for tasks requiring many details, such as for visualizing soft tissue injuries and diagnosing strokes at their earliest stages.
The magnet in closed MRI scanners is generally larger and more powerful than those in closed MRI scanners, notes UC Davis Health System. The strength of the magnet determines image quality and scan time. Fortunately, some open MRIs have larger magnets that are comparable in strength to those in traditional MRI scanners, providing an option for patients with claustrophobia.