CT, or CAT Scan

Computed tomography - more commonly referred to as CT, CT scan or CAT scan - uses x-rays and advanced computer technology to generate detailed cross-sectional, and if needed, three-dimensional views of the body's internal organs and body structures. CT scans are used to identify normal and abnormal body structures, as well as guide procedures. The exam is painless.

The CT scanner is a large donut-shaped machine that takes X-rays at different angles around the body. A CT technologist will explain the procedure to the patient and have the patient lie down on a narrow table. The CT technologist will move to a room adjacent to the exam area where s/he can observe the patient, supervise the exam and monitor the images on the screen.

The table will glide through the scanner’s “donut hole,” while the technologist, via intercom, instructs the patient to lie very still, and on occasion, hold his/her breath as the X-rays are taken.  The “donut ring” will rotate around the patient, taking X-rays from all angles.  Often a clicking or buzzing sound is heard as the table moves and the cylinder turns.  The digital X-rays are processed on a computer to produce high resolution image “slices” of the body, which are visualized on the computer monitor.  The actual CT scan takes only minutes, but, depending upon the area being scanned, exam times are from 15 to 30 minutes.

Some CT exams require a contrast material to highlight areas of the body.  Depending upon the area being scanned, the contrast may be given orally, intravenously, or a combination of methods.

Patients are asked to notify their healthcare provider if they 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.

Patients are generally asked to not eat or drink anything 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.

Once at PIC, patients will change into a gown and be asked to remove jewelry and watches.  A locker is available to secure clothing and personal items. The technologist will review the procedure and if needed, provide the patient with 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.

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.

Images from the CT exam are reviewed and interpreted by a PIC 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 healthcare provider for the results of their CT exam.

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.

Preparing for an Abdominal CT Scan
Do not eat or drink anything four (4) hours prior to examination. Thirty minutes before exam, drink one bottle of oral CT contrast.  This contrast is available at our Front Desk, or often is given to you by your healthcare provider when the exam is scheduled.

Preparing for an Abdominal/Pelvic 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.

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.

Screening for cancer means testing for cancer before there are any symptoms. Now there is a test that can reduce death from lung cancer through early detection. The test is not recommended for everyone and it has risks as well as benefits. Here is a discussion to help you decide.


Q: Am I a candidate for lung cancer screening?Lung Cancer Screening

A: If you are:

  • a current or former smoker
  • and in the age group from 55 to 80 years (Medicare age range is 55-77)
  • and with a smoking history of at least 30 pack-years (this means 1 pack a day for 30 years, 2 packs a day for 15 years, etc.)

You are in the group at highest risk for lung cancer and screening for lung cancer is recommended.


Q: Should I get a CT scan to screen for lung cancer?

A: Talk to your own doctor about getting a CT scan to screen for lung cancer. Screening for lung cancer may save your life. Discuss your complete health history and ask for a clear explanation about the possible benefits and risk. There are some risks and not everyone should be screened for lung cancer. Only low-dose CT scans are recommended for screening. Chest X-rays are not recommended for lung cancer screening.


Q: What happens if I choose to get a CT scan for lung cancer?

A: There is some radiation risk with a CT scan and you may need to have additional tests and procedures. You should go to a hospital or screening center that has a team of experts who will clearly explain the procedure to you. The team should tell you about all the risks and benefits of the screening. They should also discuss what the results can mean and how they will follow up with you after the initial screening.


Q: What does it cost to have a CT scan for lung cancer?

A: The cost at Providence Imaging Center is approximately $550.00. Be sure to check with your insurance plan to see what is covered. Ask your doctor and the facility doing the CT scan to carefully and clearly explain all costs that you may possibly be charged and not just the cost of the CT scan alone.


Q: What do the results mean?

A: A “suspicious” result means that the CT scan shows something is abnormal. This could mean lung cancer. It could also mean some other condition. You may need to have additional procedures to find out exactly what is abnormal. If you do have lung cancer or some other condition, your doctor and the team of experts should discuss all possible treatment options with you. A “negative” result means that there were no abnormal findings at this time on this CT scan. It does not mean you absolutely do not have lung cancer. It does not mean that you will never get lung cancer. Your doctor should discuss when and if you should be tested again. Remember: The best way to prevent lung cancer is to never smoke or to stop smoking now. If you are still smoking, talk to your doctor about ways to help you quit smoking.


Q: I have Medicare. Will it pay for a lung cancer screening?

A: Yes. As of February 5, 2015, Medicare will pay for this test if you are age 55-77, and fit the criteria detailed in the decision memo released by CMS. Your provider must follow certain steps that include a lung cancer screening couseling and shared decision making visit. Ask your primary care provider for more information. Two Providence facilities in Anchorage currently accepting Medicare patients: the Providence Senior Care Clinic, and the Providence Family Medicine Center.


Q: I am from a provider’s office that would like to order this test for my patient. Where do I find your order form?

A: Find a copy of our new lung cancer screening order form on our Forms page. or download the PDF here.


Q: Where can I get more information about lung cancer and lung cancer screening?

A: You can contact the American Lung Association to find out more about lung cancer and lung cancer screening. Go to: www.Lung.org or Call: 1-800-LUNG-USA (1-800-586-4872)


Other resources for patients and providers are listed here:

For Patients

The American Lung Association has lung cancer education resources for patients and physicians.

Decision from the U.S. Preventive Services Task Force in a simple four page PDF.

CMS (Centers for Medicare & Medicaid Services) lung cancer screening decision memo. This includes a summary followed by detailed recommendations and requirements.

The University of Michigan has published a shared decision-making tool that will help physicians and patients make informed decisions about low-dose CT (LDCT) lung cancer screening. The tool is now available for use at shouldiscreen.com

An online resource for those who wish to learn more about smoking cessation – Smokefree.gov

For Providers

This article from Science Direct is written with primary care providers in mind.

Lung Cancer Screening with Low-Dose Computed Tomography for Primary Care Providers

Three page PDF file for providers from the USPSTF that summarizes what you should know when talking with your patients about screening for lung cancer.

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