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Jackson Radiological Group
 What
is a CT or CAT scan?
Computed Tomography (CT) System, also know as a "CAT Scan" is a
medical diagnostic tool that allows the visualization of internal
structures within the human body. This aids physicians in diagnosing
disease, viewing internal abnormalities and assessing the extent
of trauma damage.
During a typical CT procedure, the patient is placed on a table.
The table then moves the patient through the gantry (a donut-shaped
device), which houses an X-ray tube and detector array. For each
image acquired, the X-ray tube rotates around the patient and the
X-rays pass through the patient to the detector array, and thousands
of X-ray measurements are acquired. The computer then processes
this information and displays the corresponding images on a computer
screen. (See Figure 1) This imaging technique avoids any superimposition
of organs or tissues upon one another that might occur during other
types of X-ray tomographic studies.
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The CT exam creates images analogous to a single
slice of bread from a whole loaf or a slice from an orange. (See
Figure 2) Hence, the word 'slice' is often used to describe a view
of patient anatomy.
The quality of an image depends on the nature of the X-ray source
and detectors, the number and speed of the measurements made, the
details of the reconstruction technique (algorithm), the machine
characteristics, and the methods of data display and interpretation.
The computer allows healthcare professionals to shade, rotate, correlate
and measure anatomy in the image. This data can be manipulated to
derive even more precise clinical information. While conventional
X-ray can discern tissue density difference of five percent, CT
can distinguish a density difference of 1 percent or less, aiding
in diagnostic confidence.
For more information, visit RSNA's radiologyinfo.org
website.
Is there anything I will need to do before the study?
If you are having a CT of your abdomen and/or pelvis, you might
have to drink oral contrast material which is given to coat the intestines.
This is usually given 1 1/2 hours before the exam. Therefore,
we ask that you have nothing to eat or drink after midnight
on the night before your exam.
Depending on the type of CT you are having, you may need intravenous
or "IV" contrast which will be given through an IV line immediately
before the study. IV contrast is given to enhance the blood
vessels that feed your organs. We ask that you do not eat a
heavy meal before your exam as, occasionally, patients receiving
IV contrast who have had a heavy meal may experience mild nausea.
During the study, IV contrast may make you feel warm all over.
This can last for about 1 minute and is normal.
Please let us know ahead of time if you have a history of kidney
disease or renal failure. If this is the case, you may need
a blood test to determine your kidney function if you are to
receive IV contrast.
If you are having a CT that requires IV contrast and are taking
a medication for diabetes known as Metformin (Glucophage, Glucovance,
etc.), you will need to stop taking this medication two days
before your exam. Also, your doctor may need to order labwork
to check your renal function. Your doctor will be aware what
to do in this event.
We recommend drinking plenty of fluids after your exam to flush
both the IV and oral contrast from your system.
Do I need to bring anything with me?
Bring your insurance cards. Your insurance may require you to
make a co-payment.
If you have had previous CT studies from another facility not
covered by the Radiological Group, please try to bring us a copy
of that study and/or study report, if possible.
What should I wear?
We recommend wearing comfortable clothes that do not contain
any metal in the area we are going to be imaging. We have gowns for you to change into in cases where this is
needed.
What happens when I arrive to your facility?
Take the elevator to the second floor and check in with the
receptionist at the front desk. The receptionist may have information
for you to fill out once you arrive (these forms are also available
online. If you wish to fill them out ahead of time, click
here).
Once all your information has been obtained and processed, your
technologist is notified of your arrival.
How is the study performed on me?
The technologist will take you to the CT suite and ask you a
series of history questions that aid in the reading of your
exam. If needed, you may be given a cup of oral contrast to
drink. If IV contrast is needed, the technologist will start
an IV line. Once everything is ready, the technologist will
start your study. You may
be given breathing instructions during your study if needed
for your exam.
What can I do to make sure my exam is optimal?
During a CT scan, the images are obtained in a matter of seconds.
During the scan, you are asked to hold still and sometimes hold
your breathe for a few seconds. Following these instructions
can improve the image quality of your study.
How long will it take to do the study?
CT studies usually range from 5-10 minutes though may be longer
if it is determined during your study that additional images
are needed.
What happens to me after the study is over?
Any IV line will be removed. If you are undressed for the exam,
you are taken back to the dressing room to put your clothes
back on. Once the radiologist reviews your study and it is determined
that no additional images or studies are needed, you will check
out at the front desk. Depending on the order from your doctor,
you will either stay while the report is given to your doctor
or you will be free to leave and your doctor will discuss the
study and results with you at a later time.
If a copy of the CT exam is needed, a CD of the study or films
can be given to you. |
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