Computerized Tomography Scan (CAT/CT)

Also known as: CT Scan, CAT Scan

At Providence, our CT scans are designed to image the body with a high level of clarity and precision. It allows our doctors to provide more accurate diagnoses, better treatments and more positive outcomes for all our patients.

A computerized tomography scan, or CT scan for short, is a diagnostic imaging procedure that uses a combination of X-rays and computer technology to produce clear, high-resolution images – often called slices – of the body, including bones, organs, even blood vessels.

CT scans were designed to allow doctors to image the body from different directions and are more detailed than conventional X-rays. Because a CT scanner is circular and rotates around the body, the machine is able to deliver X-rays from different angles along a rotating gantry. Those images, or “slices,” can be seen in 2-D or stacked together to create 3-D cross-sections on a computer.

CT scans allow your doctor to pinpoint afflictions almost anywhere on the body for surgeries, treatments or emergencies. The scans help examine blood clots, fractures and broken bones, tumors, internal injuries to the head, chest, abdomen and pelvis or internal bleeding, and can screen for signs of heart and vascular disease and muscle disorders.

Generally we ask that you do not eat or drink anything but water for at least four hours prior to the exam. If CT oral contrast is ordered, drink it according to the directions and time provided for the specific CT exam. 

Please notify your provider if you are pregnant; have asthma or allergies to medications, contrast dye, or iodine; or have certain medical conditions such as diabetes, asthma, heart disease, kidney problems or thyroid conditions.

At the imaging center you will change into a gown. The technologist will review the procedure and if needed, provide additional CT oral contrast to drink. If intravenous contrast is needed, it will be administered at the start of the exam. Patients may experience a warm sensation throughout the body after the contrast injection and a metallic taste in the mouth. These sensations typically disappear in a few minutes.

  • Prepare for an abdominal CT scan

    Because CT imaging is a non-invasive procedure that shows detailed, cross-sectional views of all types of tissue, it is becoming the preferred method for visualizing and diagnosing diseases of the liver, spleen, pancreas, kidneys, bladder, bowel and colon.

    Abdominal CT scans are used to monitor tumors and other conditions of the abdomen before and after treatment, and to detect, diagnose and treat vascular disorders that may lead to stroke, gangrene or kidney failure.  The CT's acute detail and accuracy may eliminate the need for invasive exploratory surgery and surgical biopsy. Please note, CT accuracy may be compromised due to metallic objects in the abdomen, such as surgical clips, barium in the intestines from a recent barium study; and stool and/or gas in the bowel. Please advise the CT technologist if you have clips or have had a recent barium study.

    Do not eat or drink anything except water four (4) hours prior to examination. Thirty minutes before exam, drink one bottle of oral CT contrast.  This contrast is available at imaging centers, or often is given to you by your healthcare provider when the exam is scheduled.

  • Preparing for a pelvis CT scan

    If the exam is scheduled before 11 a.m., patients should drink one bottle of oral CT contrast at 9 p.m. the night before the exam.  Eat and drink as usual after taking the oral contrast until midnight. Do not eat anything after midnight until 30 minutes prior to the exam, when the second bottle of oral CT contrast will be consumed.

    If the exam is scheduled after 11 a.m., drink one bottle of oral CT contrast four (4) hours prior to the exam time.  Do not eat anything after the first bottle of oral CT contrast. Thirty minutes prior to the exam, drink a second bottle of oral CT contrast.

    If intravenous contrast is needed, it will be administered at the start of the exam. Patients may experience a warm sensation throughout the body after the contrast injection and a metallic taste in the mouth. These sensations typically disappear in a few minutes. If rectal contrast is needed, a small tube will be placed in the rectum and contrast will be infused into the bowel, similar to an enema, at the start of the exam.

  • Preparing for a pulmonary CT scan

    A CT scan shows detailed images of any part of the body, including bones, muscles, fat and organs.

    CT scans of the chest provide more detailed information about organs and structures inside the chest than standard x-rays, making it an excellent tool for assessing the chest and its organs for tumors and other lesions, injuries, intra-thoracic bleeding, infections, unexplained chest pain, obstructions or other conditions. It may also be used to evaluate the effects of treatment on thoracic tumors.

    Patients are asked to notify the CT technologist if they have metal objects within the chest, such as a pacemaker or surgical clips or have had a recent barium study as these may interfere with the accuracy of a CT scan of the chest.

    If no contrast medium is required, patients may stay on their regular diet.

Depending on the part of your body your scan will focus on, you will receive a dosage of a contrast dye either through a drink, an injection, or an IV. The dye allows your organs and bones to appear clearly within the images. 

During the scan, you lie on a moving bed that enters through the CT scanning machine. The scanning machine looks like a small tunnel that wraps itself around your entire body. The tunnel delivers and picks up low-dosage radiation to image the different organs and bones in your body.

The CT scanning machine then sends the digital X-ray information received to a computer controlled by a radiologist and located in a separate room. The computer processes the information to produce the slices and cross-sections for analysis.

Your radiologist monitors you and the CT scanner throughout the entire process. Should you feel uncomfortable or need assistance, a microphone allows you to speak to them at all times. 

The entire procedure takes roughly 30 minutes with the scan itself taking no longer than 10.

Your scan results

Images from the CT exam are reviewed and interpreted by a radiologist, who will dictate a report, which is transcribed and sent to the healthcare provider who ordered the exam. This is usually accomplished within 3 days after the exam. Patients should contact their provider for the results of their CT exam.

We use low-dosage technology to minimize ionizing radiation exposure while still maintaining a good image quality for an accurate diagnosis. Other than the slight radiation exposure, CT scans have not been shown to cause long-term harm to your health.

During the procedure, some side effects are possible and usually limited to reactions to the contrast dye. These include itchiness and soreness, as well as a warm, metallic taste in the mouth and the false sensation of urination.

Occasionally a patient may be allergic to the contrast material. Reactions may include sneezing, hives or difficulty breathing. Anyone having a reaction will be treated prior to his or her release.

After the procedure, drink plenty of fluids for several hours to assist in flushing out the contrast material. Normal activity and diet can be resumed.

Doctors Specializing in Computerized Tomography Scan (CAT/CT)

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