X-rays and cat scans?

just a simple question. My husband has been in for 3 x-rays, doctor has only said that he has a nodule, but dr. office called today and said they want him to have a cat scan. any ideas . I am very curious trying not to be concerned. just want to hear throughts or if anyone has experienced this

CAT Scans
So what's a CAT scan, anyway?

"Computed Axial Tomography" is the process of using computers to generate a three-dimensional image from flat (i.e, two-dimensional) x-ray pictures, one slice at a time...

What do you mean by "slice"?

Well, imagine trying to visualize the inside of something like a fruitcake.

A fruitcake?

There's a lot of complexity on the inside that you can't guess from the outside, bits of fruit and nuts all over the place. How could you go about exploring the inside of a whole fruitcake?

Oh, I see what you mean now. If I sliced it up I could look at each slice and get an overall picture.

Right! Well, CAT Scanners do the same thing, but rather than actually cut people up, they use x-rays to make pictures of the slices. (There is an effort underway, called the Visible Human Project, where they are actually slicing up a (very dead) person and photographing each thin slice.)

OK, but we just said that CAT scans are useful because x-ray machines only take flat, two dimensional pictures and we want three dimensional pictures. So why is the process of imaging the flat "slices" difficult? Isn't making flat pictures what x-ray machines do?

The problem is that the flat x-ray we get is of the whole thing. It would be like crushing our fruitcake under a steam roller and saying, "There! Now we can see everything!" But we would have lost all the information about how "deep" the pieces of fruit and nuts were.

So how do we take x-rays of a slice in the middle? We could just turn the fruitcake sideways, but then all the other slices would get in the way. How do we take x-rays of only one slice?

Very good! That's exactly the right question to ask. Let's explore that.

Without knowing what the underlying condition is or even what has been x-rayed and what's to be CTed this isn't easy to answer.

At the base level; do people routinely have CT scans after X-rays? Yes, all the time.





@ tiger, your CTRL, C & V buttons might have had an easier life if you'd just posted the link http://www.colorado.edu/physics/2000/tom...

Just x-rays don't give enough information. A CAT scan actually shows the area from all angles and the Doc can tell what kind of nodule it is. Don't worry until you have something to worry about. You will have more than one doctor looking at the results. Good luck!

I am going to assume that they saw the nodule on a chest xray and the nodule is in the lung. Since the regular chest xray is a flat film, they cannot tell what the nodule is. A CT scan will scan his chest area and give images that are like looking at slices of bread. It also shows better detail of the nodule and it density. They also us contrast material injected in a vein that will highlight and show any blood flow etc to the nodule which will give them a better idea of what they are looking at. When I worked as a CT assistant, they would scan the area first without the contrast and then inject it and scan again so that they could see the difference between the two images.

Try not to get too concerned at this time. We had numerous nodule patients who had benign nodules that went away even though there is a chance of benign nodules too. Hopefully you will have a CT tech that will have the chance to explain to you a little better what is going on and why they are doing the scan.

I hope this helps a little.