CT Scan
What is a CAT Scan?
A CAT scan, also called CT, or computed tomography, is an imaging technique that produces cross-sectional images of the body's internal organs. CT scans use an X-ray unit that rotates around your body and a computer to create cross-sectional images, or slices, of the inside of your body. Imagine the body as a loaf of bread, and you are looking at one end of the loaf. As you remove each slice of bread, you can see the entire surface from the crust to the center. The body is seen on CT scan slices in a similar fashion from the skin to the central part of the organ being examined. When these levels are further added together, three-dimensional pictures of an organ or abnormal body structure can be obtained.
why order a cT scan?
Your doctor may recommend a CT scan to:
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Diagnose muscle and bone disorders, such as bone tumors and fractures.
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Locate tumors, infections, or blood clots.
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Detect and monitor conditions such as cancer or heart disease.
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Detect internal injuries and internal bleeding.
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Guide procedures such as surgery, biopsy, and radiation therapy.
What to expect when having a cT scan:
You can have your CT scan at the hospital or outpatient imaging center (AOIC). NOTE: If you are allergic to IV contrast, and your test requires this injection, you must have your CT at the hospital where medications to treat a possible allergic reaction are readily available.
When having a CT scan, you like on a table inside a doughnut shaped machine called a gantry, while the x-ray tube inside the gantry rotates around your body taking multiple images. The table will move as the images are being acquired. The procedure lasts no longer than an hour depending on the preparation and whether or not an IV contrast injection is needed. The actual scan itself may take less than several minutes to complete. While the table is moving, you may need to hold your breath to avoid blurring of the pictures. During this time, the technologist is in an adjacent, shielded room supervising and monitoring the images as they appear on the computer screen. During the entire scanning process, the technologist can see and hear you, and you may communicate by intercom.
CT scans are basically painless. If your examination requires the use of an IV contrast, the technologist will need to start an IV in your arm or hand. The IV contrast will give you a brief, warm sensation in the back of your throat and in the bladder area. you may get a metallic taste in your mouth. Some of the CT scans of the abdomen and pelvis require that the patient drink an oral contrast medium two hours before the scan. The oral contrast coats the stomach, small bowel, and colon giving better-detailed images. you may be asked to drink more oral contrast before the actual scan is started.
after your CT scan:
After your examination, you may return to your normal routine. If you were given a contrast medium, either orally or intravenously, you may be asked to drink extra liquids for a day following the scan in order to flush the contrast from the kidneys.
preparation for a CT scan:
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Renal (Kidney) Screening: Any patient ordered a CT scan WITH IV CONTRAST must have a BUN and Creatinine done if they are:
- 64 years of age or older
- Diabetic
- Hypertensive
- Suffer from Multiple Myeloma
- You have any kidney problems (renal failure, or have only one kidney)
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Pregnant Women: If you are pregnant or suspect you might be, inform your doctor. Your doctor may suggest postponing the test or choosing an alternative procedure.
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Various Tests And Preparations: This is a list of CT exams that require preparation. You may be ordered an exam that does not appear on this list that would indicate there is no special preparation required before your CT exam. These exams are grouped according to either preparation #1, #2, or #3.
- Abd/pelvis combined w reconstruction (Urography) (Prep #1)
- Brain (Prep #1)
- Chest (Prep #1)
- CT Chest Angio Combined(PE) (Prep #1)
- CTA (Computed Tomography Angiography)
- All CTA exams require (Prep #1)
- Head angio combined (Circle of Willis)
- Neck angio combined (Carotids)
- Chest/Abd/Pelvis angio combined (Aorta)
- Abd/pelvis angio combined (AAA)
- Aorto-femoral angio combined (PVD)
- Soft Tissue Neck (Prep #1)
- Abdomen (Prep #2)
- Abdomen/Pelvis Complete Survey (Prep #2)
- Pelvis (Prep #2)
- Guidance for Abscess Drainage (Prep #3)
- Guidance for Cyst Aspiration (Prep #3)
- Guidance for Needle Biopsy (Prep #3)
This blood test will determine if the kidneys are functioning properly before an IV injection of contrast is given.
| Prep #1: Clear liquids only 6 hours prior to exam. | |
| Prep #2: Clear liquids only 6 hours prior to exam, drink bottle of Redi-cat 2 hours prior to exam. (Redi-cat may be obtained from the ACMH Imaging Services Department. | |
| Prep #3: Nothing to eat or drink after midnight before exam. |
CT SCAN RISKS:
A CT scan is a very low risk procedure. During the CT scan you are briefly exposed to radiation, but doctors and scientists believe that CT scans provide enough valuable information to outweight the associated risk.
The most common problem is an adverse reaction to the IV contrast. The IV contrast is usually an iodine based liquid given in the vein through an IV. The IV contrast makes many organs and structures, such as the kidneys and blood vessels much more visible on the images. An allergic reaction may consist of itching, rash, or hives. These are usually self-limiting reactions and usually disappear rather quickly. Antihistamines may be given to help relieve the symptoms.
A more serious reaction to IV contrast would be difficulty breathing, which is quite rare but is potentially life threatening if not treated. Medications such as antihistamines and epinephrine and corticosteroids reverse this adverse reaction and are readily available in the hospital setting.
A patient may be pre-medicated with the corticosteroids and antihistamines prior to the CT scan if he/she has had a slight reaction such as hives or rashes during a prior CT scan. Please consult your doctor with any question or fears you may have concerning pre-medication for the CT scan.
results of a cT scan:
CT images are stored as electronic data files and reviewed on a computer. The radiologist interprets these images and sends a report to your doctor. Your doctor should contact you with the results. If you do not hear from your physician within a week, contact his/her office.
cT scan for children:
A thorough explanation of the procedure will be given to the parent/legal representative. A parent or legal representative is required to be with a patient under the age of 18 in order to sign a legal consent. A child may sign their own consent at the age of 18. A parent/legal representative may be permitted to stay with a child during the scan which is determined on a case-by-case basis. The parent/legal representative and child will wear lead aprons to shield them from unnecessary x-ray exposure.
Invasive procedures using cT scanning:
This technique is relatively painless and can provide extremely accurate images of body structures. In addition this guides the radiologist in performing procedures such as biopsies for suspected cancers, removal of internal body fluids for various tests, and draining of abscesses deep within the body. Many of these procedures have decreased the need to perform surgery to accomplish the same goal Invasive procedures are scheduled by your physician through the Ambulatory Surgery Department and Radiology Scheduling.
ACMH Hospital: Monday through Friday -- 8:00 am to 5:00 pm for enhanced and unenhanced CT Scans; 5:00 pm to 8:00 pm for unenhanced CT Scans only.
Saturday -- 8:00 am to 12:00 pm enhanced and unenhanced scans
CT scanning is available 24 hours a day, 7 days a week for emergency procedures at the hospital.
AOIC: Monday, Tuesday, Thursday, Friday -- 8:00 am to 4:30 pm
Wednesday -- 9:00 am to 5:00 pm
Scans completed at the AOIC are unenhanced (no IV contrast) only.
outpatient scheduling for CT Scans:
You may call our scheduling department at 724-543-8131 to schedule an appointment at the ACMH Hospital or AOIC.
If you have any questions concerning your CT scan, please feel free to call us at 724-543-8488 between the hours of 7:00 am and 11:00 pm, seven days/week. If a technologist is not available when you call, please leave your name and number and they will return your call at their earliest convenience.