12041

What is the difference between an X-ray, CT, and MRI scan?


WRITTEN BY: Imaging Services
Saturday, April 5th, 2014

Often patients will be referred for an imaging exam to reaffirm good health, or to let physicians take a look at a certain part of the body in closer detail.  Your primary care provider is more than happy to educate you about what these exams entail. Here, we discuss the differences between three commonly used imaging exams.

X-Ray

What x-rays look for

X-rays are commonly used to spot broken bones, but can also detect pneumonia, types of cancers, and other developing conditions.

What to expect during an x-ray

In this exam, an x-ray machine sends individual x-ray particles through the body, which are recorded as images on a computer. This exam is painless, however it may require you to stand still for a short period of time which can cause temporary discomfort.

Length of x-ray exam

The length of the x-ray depends on the body part being examined; however it typically takes a matter of minutes.

Computed Tomography (CT)

What CT scans look for

Physicians use CT scans primarily to look at the soft tissues of the body and various organs.  CT scans can also diagnose an infection, however they can also be used to guide a surgeon to the right area during a biopsy, identify masses and tumors, including cancer, and study blood vessels.

What to expect during a CT scan

You will be asked to lie on a table that slides into the center of the CT scanner. Once you are inside the scanner, the machine’s x-ray beam rotates around you. A computer creates many different images of the body, called slices, which can be viewed on a monitor by the radiologist.  You will be asked to remain still during the exam to avoid blurred images. Often times you will be asked to drink a contrast for the CT scan.  This allows the radiologist to highlight certain areas for a clearer image.  The contrast will be provided to you when you arrive for your test.

Length of CT scan

Complete scans usually take only a few minutes.

Magnetic Resonance Imaging (MRI)

What MRI scans look for

MRIs are used to detect diseases or abnormalities throughout the body, such as brain aneurysms or tumors, but also are often used as a “second look” if other imaging scans provide inconclusive results. No radiation is used in an MRI exam.

What to expect during a MRI

Before an MRI, you will be asked to remove all metal to avoid interaction with the magnet. You will lie on a table, which slides into a large tunnel-shaped scanner. Some exams require a special dye (contrast), which is given through a vein (IV) in your hand or forearm before the test. The dye helps the radiologist see certain areas more clearly. During the scan, the technician will watch you from another room to ensure you are comfortable and give updates on the status of the exam.

Length of MRI Scan

Depending on the area of concern, an MRI can last between 30 and 60 minutes.

Still have questions? Let us know in the comments below.

 

imaging services

Imaging Services

UPMC Imaging Services offers access to the most advanced imaging technology, including 64-slice CT and wide-bore MRI. We also offer the expertise of on-site, sub-specialty trained radiologists who provide fast, high-quality readings. Read More