For information about radiation exposure and medical imaging click here.

Did you know?
Rated by JAMA, we employ a state-of-the-art 128-slice CT scanner, which utilizes the lowest amount of radiation while producing the highest resolution images.

Peninsula Imaging also participates in the Image Gently campaign which ensures CT examinations are performed with the lowest possible dose of radiation.

You have been given an appointment card for a computed tomography (CT) scan. Computed tomography scans- CT or CAT scans, as they're commonly called- create detailed images of the body using X-rays. CT imaging aids us in identifying diseases in their early stages when the likelihood for a cure is at its greatest.

CT scans give your doctor far more information than most standard X-ray images. They create three-dimensional images in lifelike detail to help show your doctor what's happening in your body.

CT scans are often used to examine detail of the brain, heart, airway, lungs, bones, tissue and blood vessels. CT can help diagnose pain from injuries and fractures. It is also a helpful tool for aiding in the diagnosis of cancer and monitoring treatments.


Looking for Virtual Colonoscopy? See our section specifically for this.
Looking for Lung Cancer Screening? See our section specifically for this.

Help Center

Why would I need a CT?
How High is the Risk?
How should I prepare?
What should I expect during this exam?
What will I experience during the procedure?
When and how will I find the resulsts of my test?
Are there any health risks associated with CT Scan?

Why would I need a CT?


CT is used for many reasons, including but not limited to:

CT of the Head
  • CT scanning of the head is typically used to detect:
    • Bleeding, brain injury and skull fractures in patients with head injuries
    • Bleeding caused by a ruptured or leaking aneurysm in a patient with a sudden severe headache
    • a blood clot or bleeding within the brain shortly after a patient exhibits symptoms of a stroke
    • a stroke, especially with a new technique called Perfusion CT
    • brain tumors
    • enlarged brain cavities (ventricles) in patients with hydrocephalus
    • diseases or malformations of the skull
  • It is also used to:
    • evaluate the extent of bone and soft tissue damage in patients with facial trauma, and planning surgical reconstruction
    • Diagnose diseases of the temporal bone on the side of the skull, which may be causing hearing problems.
    • Determine whether inflammation or other changes are present in the paranasal sinuses.
    • Plan radiation therapy for cancer of the brain or other tissues.
    • Guide the passage of a needle used to obtain a tissue sample (biopsy) from the brain.
    • Assess aneurysms or arteriovenous malformations through a technique called CT angiography.

CT of the Sinuses
  • CT scanning of the sinuses is used to:
    • Detect the presence of inflammatory diseases
    • Plan for surgery by defining anatomy or giving further information about tumors of the nasal cavity and sinuses
    • Evaluate sinuses that are filled with fluid or thickened sinus membranes
    • Help diagnose sinusitis
CT of the Body is used to:
  • Quickly identify injuries to the lungs, heart and vessels, liver, spleen, kidneys, bowel or other internal organs in cases of trauma
  • Plan for and assess the results of surgery, such as organ transplants or gastric bypass
  • Stage, plan and properly administer radiation treatments for tumors as well as monitor response to chemotherapy
  • Measure bone mineral density for the detection of osteoporosis
CT of the Chest is used to:
  • Further examine abnormalities found on conventional chest x-rays
  • Help diagnose the cause of clinical signs or symptoms of disease of the chest, such as cough, shortness of breath, chest pain, or fever
  • Detect and evaluate the extent of tumors that arise in the chest, or tumors that have spread there from other parts of the body
  • Assess whether tumors are responding to treatment
  • Help plan radiation therapy
  • Demonstrate various lung disorders
CT of the Abdomen and Pelvis is used to:
  • This procedure is typically used to help diagnose the cause of abdominal or pelvic pain and diseases of the internal organs, bowel and colon, such as:
    • Infections such as appendicitis, diverticulitis or infected fluid collections (abscesses)
    • Inflammatory processes such as pancreatitis, pyelonephritis or inflammatory bowel disease such as Crohn's disease
    • Cancer's of the colon, liver, kidneys, pancreas and bladder as well as lymphoma
    • Kidney and bladder stones
    • Abdominal aortic aneurysms (AAA) and other diseases of the vessels such as blood clots and abnormal narrowings or stenoses of the vessels
    • Quickly identify injuries to the liver, spleen, kidneys or other internal organs in trauma cases
    • Plan for and assess the results of surgery, such as organ transplants or gastric bypass
    • Stage, plan and properly administer radiation treatments for tumors as well as monitor chemotherapy treatment
CT of the Spine:
  • Some common uses of CT of the spine include:
    • Detect or rule out spinal column damage in patients who have been injured
    • Evaluate the spine before and after surgery
    • Detect various types of tumor in the vertebral column, including those that have spread there from another area of the body
    • Help diagnose spinal pain
    • Measure bone density
Coronary Computed tomography Angiography (CTA):
  • Coronary computed tomography angiography (CTA) is a heart imaging test that helps determine if fatty or calcium deposits have narrowed a patient's coronary arteries. Coronary CTA is a special type of x-ray examination. Patients undergoing a coronary CTA scan receive an iodine-containing contrast material as an intravenous (IV) injection to ensure the best possible images.
    Candidates for Coronary CTA include but are not limited to patients who have:
    • Arrived at the Emergency Room with chest pain
    • Suspected abnormal coronary arteries
    • Low to intermediate risk for coronary artery disease, but have symptoms such as chest pain which are not brought on by physical activity
    • Unclear or inconclusive stress test results
    • Intermediate to high-risk for coronary artery disease,; but who do not have typical symptoms like chest pain, shortness of breath, or fatigue during heavy physical activity
Cardiac CT for Calcium Scoring:
  • A cardiac CT scan for coronary calcium is a non-invasive way of obtaining information about the presence, location and extent of calcified plaque in the coronary arteries - the vessels that supply oxygen-containing blood to the heart muscle. Calcified plaque results when there is a build-up of fat and other substances under the inner layer of the artery. This material can calcify which signals the presence of atherosclerosis, a disease of the vessel wall, also called coronary artery disease (CAD).

    People with this disease have an increased risk for heart attacks. In addition, over time, progression of plaque build up (CAD) can narrow the arteries or even close off blood flow to the heart. The result may be chest pain, also sometimes called angina in the chest or a heart attack. Because calcium is a marker of CAD, the amount of calcium detected on a cardiac CT scan is a helpful prognostic tool. The findings on cardiac CT are expressed as a calcium score - or coronary artery calcium scoring.

    The major risk factors for CAD are:
    • Abnormally high blood cholesterol levels
    • A family history of heart disease
    • Diabetes
    • High blood pressure
    • Cigarette smoking
    • Being overweight or obese
    • Being physically inactive
Back to Top

How High is the Risk?

Everyone is exposed to different sources of natural radiation in daily life. The additional exposure with X-rays from CT in medicine has to be seen in this context. Without the use of X-rays, many diseases may not be diagnosed early enough for efficient treatment. The risk of radiation from medical imaging remains extremely low and is far outweighed by the potential health benefits.

Back to Top

How should I prepare for my CT scan?


Check with our office, as most CT exams ask nothing to eat 6 hours prior to the exam. On the day of your exam, please wear two-piece comfortable, loose-fitting clothing. Avoid clothing with zippers and snaps as metal objects can affect the image. You may also be asked to remove hair pins, jewelry, eyeglasses, hearing aids or dentures depending on the part of the body to be scanned as well as asked not to eat or drink anything for one or more hours before the exam.

For CT scans of the abdomen and pelvis, you may be instructed to drink 2 or more 16-ounce glasses of contrast medium which will highlight the digestive tract on the CT images. Patients who are allergic to intravenous (IV) dye can still drink the liquid contrast without problem.

Women should inform their doctor or the CT technologist if there is any possibility that they are pregnant.

Back to Top

What should I expect during this exam?


A CT scan may take anywhere from 5 minutes to a half hour. Our Technologist will position you on our cushioned CT table and pillows may be used to help keep you still and in the proper position during the scan. Our goal is to make you as comfortable as possible. The table will move slowly into the CT scanner opening. Depending on the area of the body being examined, the increments of movement may be very small and almost undetectable or large enough to feel the motion.

To enhance the visibility of certain tissues or blood vessels, use of different contrast materials (x-ray dye) may be required. Depending on the type of examination, contrast material may be injected through an IV, swallowed or administered by enema.

Before administering the contrast material, you should inform the radiologist or technologist of the following:
  • Any allergies, especially prior allergic reactions to radiologic contrast agents
  • If you have a history of diabetes, asthma, kidney problems, heart or thyroid conditions. These conditions may indicate a higher risk of reaction to the contrast material or potential problems eliminating the material from the patient's system after the exam.
The CT technologist will step out of the CT exam room into an adjacent control room, but will be in constant visual and verbal contact with you during the brief time that the scan is actually being performed. You may be asked to wait until the images are reviewed, to determine if more images are needed.

Back to Top

What will I experience during the procedure?


CT scanning is painless. Preparation will vary depending on the type of scan you are having. To enhance the visibility of body tissue or blood vessels, use of different contrast material may be administered by mouth, intravenously, or by rectal enema.

You may be asked to drink a flavored oral contrast agent, a liquid which will allow our Radiologist to better see the stomach, small bowel and colon. Some patients find the taste of the contrast material slightly unpleasant, but tolerable. For a study of the colon, you may require the administration of the contrast material by enema. You may experience a sense of abdominal fullness and the need to have a bowel movement. Any discomfort is generally mild and easily tolerated. Our Technologist will allow you to use the restroom immediately after such an exam.

To highlight the difference between normal and abnormal tissue in organs like the liver or kidneys, or to better show blood vessels, contrast is commonly injected into a vein. You might feel:
  • Flushed or have a slight metallic taste in your mouth. These are common responses which disappear in a minute or two.
  • Nausea or queasy stomach is unusual with the newer contrast agents. If it occurs, it is usually very brief.
  • A mild itching sensation. If the itching persists or is accompanied by hives, it can be treated with antihistamine medication such as Benadryl.
  • In rare cases, you may experience shortness of breath or swelling in the throat or other parts of the body. These can be indications of a more serious reaction to the contrast material.
After your CT scan is complete, you may eat and resume normal activity. Fluid is encouraged. Any contrast material given during the procedure will pass naturally through the patient's body, usually within one day.

Back to Top

When and how will I find out the results of my test?

One of our on-staff Radiologists will interpret your CT scan and send a report to your referring physician. Your doctor will discuss the CT results with you.

Back to Top

Are there any health risks associated with CT Scan?


Our new CT equipment uses the lowest dose of radiation available nationwide. Generally, the small risks of the radiation are outweighed by the potential benefits of the information gained by the study. Our contrast agents are generally safe; however, like all medications, side effects can occur. Newer contrast materials have significantly decreased the incidence of side effects. Any allergic reactions are usually mild (itching, flushing). If you have had allergic reactions to these agents before, or if you have asthma or multiple allergies, you may be at a higher risk for a reaction. Be sure to inform your physician and our CT technologist if your have any of these conditions.

Iodine contrast can also rarely cause kidney toxicity in people with certain medical conditions, which include but are not limited to: kidney failure, diabetes, multiple myeloma, severe dehydration, hyperuicemia (may occur with gout) and heart failure. If you fall into one of these categories, or if you are over age 60, a blood test will be needed prior to the study to measure your kidney function.

Back to Top