Skip to content

Why do I need a CT AND an MRI?

October 10, 2012

If you go to a doctor or a hospital with a complaint of pain, any pain really, chances are you will get imaged.  This imaging ranges from a simple x-ray to cardiac catheterizations.  Often, you will get more than one and more than one kind.  If you go to one hospital and they transfer you to another one, chances are the second hospital will repeat the imaging studies of the first.  Why do you need more than one?  Why two kinds of imaging of the same body part?  Why repeat them?

The simplest form of imaging is the X-ray.  If you come to the doctor and say you fell and now your ankle hurts, you might get an ankle film.  If you go to the same doctor and say you fell 6 months ago and it still hurts, chances are you’ll get an MRI.  Do you need an MRI?  Probably not.  MRI tells your doctor alot more about the ligaments and soft tissue in your ankle, much less about the bone.  So if you have a torn tendon, say, the MRI will show it better.  But MRIs cost a couple of thousand bucks.  Unless you’re a professional athlete or are going to have surgery on said tendon, skip the MRI and get some physical therapy.  This is especially true for back pain.  Doctors do all these MRIs for back pain and yep, they might find something, but I’d opt for PT over surgery every day of the week and twice on Sundays.  Don’t bother.

If you come into the ER with severe headache or head trauma, you will probably not get an X-ray of your head.  This is because X-rays just shoot radiation straight through the body part, and any bone trauma would be either hard to see or hard to locate.  For head stuff most people start with a CT scan.  CT are like X-rays but they can take pictures in slices through your body, thus giving your doctor a better idea of where the problem is if there is one.  CT is also good for bone stuff, so if you have major sinus issues (sinuses and nasal passages being full of small bones), you may get a CT.  CT is also good for following a problem over time, so if you get admitted with head trauma you’ll likely get multiple head CTs.  If your CT scan is negative or equivocal, you might also get an MRI.  MRI again shows soft tissues better, and it is especially good for visualizing arteries and veins.  If you’ve had a stroke, your CT may initially be normal but show damage in a certain area of the brain later on, whereas an MRI might show you damage earlier.  If you come in with a headache, or worse yet, dizzyness, you’ll get a head CT but it will mostly likely be negative.  This is because most causes of headaches and dizzyness have nothing to do with your brain at all.
Why will a doctor in one hospital repeat an image done in another?  Some of it is a comfort thing.  Doctors at one hospital are comfortable with the radiologists they usually use and are used to their way of reading things.  Imaging studies are usually up to some degree of interpretation and clinical correlation, meaning sometimes a radiologist will find something that’s really nothing, but he doesn’t know the whole story so he will ask your doctor to take the finding and correlate it with your symptoms.  These days, most imaging studies go up on a hospital-wide imaging network that can be accessed by your doctor, but these systems are hospital-based and usually cannot be accessed by outside hospitals, so unless the first hospital sent a hard copy of the films with you, they’ll likely get repeated.  Surgeons won’t usually be satisfied with just a radiology report, that is a verbal or written report of what the radiologist has found.  They’ll want to look at the images directly.




From → Healthcare

  1. I am not positive the place you’re getting your information, but good topic. I must spend a while studying more or working out more. Thank you for great info I was in search of this information for my mission.

  2. Hi there to every body, it’s my first visit of this weblog; this weblog includes remarkable and in fact fine stuff for readers.

Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s

The Ideal Violinist

By Bayla Keyes

Eclectic Voices

Fiction, Monologues, Plays & More

Competing Diagnoses

How Americans talk about health care reform

Navigating Healthcare - Patient Safety and Personal Healthcare Management

A Guide to navigating Healthcare for parents, children and spouses who are concerned with managing their health and the health of their family

Children's Book Reviews


Dr. Vineet Arora's thoughts on medical training, patient care, healthcare policy, with tips for trainees

Wright on Health

Making complex issues in health policy and health services research accessible to all...

Dr John M

cardiac electrophysiologist, cyclist, learner

Navigating the healthcare system


Navigating the healthcare system

Whole Mama

Navigating the healthcare system

medicine for real

Navigating the healthcare system

%d bloggers like this: