What will ct scan show

These can be administered in different ways, depending on the type of CT exam being performed. It can be administered orally by drinking the agent, given intravenously, and taken via an enema in the case of a lower intestinal scan. Following the test, a patient is told to drink lots of water to help the body flush it out. Advise your radiologist and doctor about any known allergies to medications, foods, and substances like iodine, or any kidney issues — as flushing the contrast can trigger a reaction from the kidneys.

Some people exhibit side effects from the contrast agent, but most reactions are extremely mild and lead to a sensation of itchiness or a rash. However, in rare cases, it can provoke an allergic reaction, requiring the patient to remain at the center following the exam to ensure safety. Trained staff are present to assist with epinephrine if necessary.

A CT scanner is round and shaped like a cylinder with an opening. In the center is a motorized table where the patient lies down. As the table moves into the scanner, the X-ray and its detector rotate around the patient, who must lie very still keeping eyes closed and holding the breath is advisable. You'll also be asked to remove anything metal, such as jewellery, as metal interferes with the scanning equipment. During the scan, you'll usually lie on your back on a flat bed that passes into the CT scanner.

The scanner consists of a ring that rotates around a small section of your body as you pass through it. Unlike an MRI scan , the scanner doesn't surround your whole body at once, so you shouldn't feel claustrophobic.

The radiographer will operate the scanner from the next room. While the scan is taking place, you'll be able to hear and speak to them through an intercom. While each scan is taken, you'll need to lie very still and breathe normally.

This ensures that the scan images aren't blurred. You may be asked to breathe in, breathe out, or hold your breath at certain points. You shouldn't experience any after-effects from a CT scan and can usually go home soon afterwards.

You can eat and drink, go to work and drive as normal. If a contrast was used, you may be advised to wait in the hospital for up to an hour to make sure you don't have a reaction to it. The contrast is normally completely harmless and will pass out of your body in your urine. Doctors typically use this procedure to help diagnose the cause of abdominal or pelvic pain. They also use it to diagnose diseases of the internal organs, small bowel and colon, such as:.

Wear comfortable, loose-fitting clothing to your exam. You may need to change into a gown for the procedure. Metal objects, including jewelry, eyeglasses, dentures, and hairpins, may affect the CT images. Leave them at home or remove them prior to your exam. Some CT exams will require you to remove hearing aids and removable dental work. Women will need to remove bras containing metal underwire. You may need to remove any piercings, if possible.

Your doctor may instruct you to not eat or drink anything for a few hours before your exam if it will use contrast material. Tell your doctor about all medications you are taking and if you have any allergies. If you have a known allergy to contrast material, your doctor may prescribe medications usually a steroid to reduce the risk of an allergic reaction.

To avoid unnecessary delays, contact your doctor well before the date of your exam. Also tell your doctor about any recent illnesses or other medical conditions and whether you have a history of heart disease, asthma, diabetes, kidney disease, or thyroid problems.

Any of these conditions may increase the risk of an adverse effect. Women should always inform their physician and the CT technologist if there is any possibility that they may be pregnant. The CT scanner is typically a large, donut-shaped machine with a short tunnel in the center. You will lie on a narrow table that slides in and out of this short tunnel. Rotating around you, the x-ray tube and electronic x-ray detectors are located opposite each other in a ring, called a gantry. The computer workstation that processes the imaging information is in a separate control room.

This is where the technologist operates the scanner and monitors your exam in direct visual contact. The technologist will be able to hear and talk to you using a speaker and microphone.

In many ways, a CT scan works like other x-ray exams. Different body parts absorb x-rays in different amounts.

This difference allows the doctor to distinguish body parts from one another on an x-ray or CT image. A conventional x-ray exam directs a small amount of radiation through the body part under examination. A special electronic image recording plate captures the image.

Bones appear white on the x-ray. Soft tissue, such as the heart or liver, shows up in shades of gray. Air appears black. With CT scanning, several x-ray beams and electronic x-ray detectors rotate around you. These measure the amount of radiation being absorbed throughout your body. Sometimes, the exam table will move during the scan. A special computer program processes this large volume of data to create two-dimensional cross-sectional images of your body.

The system displays the images on a computer monitor. CT imaging is sometimes compared to looking into a loaf of bread by cutting the loaf into thin slices. When the computer software reassembles the image slices, the result is a very detailed multidimensional view of the body's interior.

Nearly all CT scanners can obtain multiple slices in a single rotation. These multi-slice multidetector CT scanners obtain thinner slices in less time. This results in more detail.

Modern CT scanners can image large sections of the body in just a few seconds, and even faster in small children. Such speed is beneficial for all patients.

Speed is especially beneficial for children, the elderly, and critically ill — anyone who finds it difficult to stay still, even for the brief time necessary to obtain images. For children, the radiologist will adjust the CT scanner technique to their size and the area of interest to reduce the radiation dose. The technologist begins by positioning you on the CT exam table, usually lying flat on your back. CT exams are generally painless, fast, and easy.

Multidetector CT reduces the amount of time that the patient needs to lie still. Though the scanning itself causes no pain, there may be some discomfort from having to remain still for several minutes. If you have a hard time staying still, are claustrophobic or have chronic pain, you may find a CT exam to be stressful. The technologist or nurse, under the direction of a physician, may offer you some medication to help you tolerate the CT scanning procedure.

If the exam uses iodinated contrast material, your doctor will screen you for chronic or acute kidney disease. The doctor may administer contrast material intravenously by vein , so you will feel a pin prick when the nurse inserts the needle into your vein. You may feel warm or flushed as the contrast is injected. You also may have a metallic taste in your mouth. This will pass. You may feel a need to urinate. However, these are only side effects of the contrast injection, and they subside quickly.

When you enter the CT scanner, you may see special light lines projected onto your body. These lines help ensure that you are in the correct position on the exam table.

With modern CT scanners, you may hear slight buzzing, clicking and whirring sounds. These occur as the CT scanner's internal parts, not usually visible to you, revolve around you during the imaging process. You will be alone in the exam room during the CT scan, unless there are special circumstances. For example, sometimes a parent wearing a lead shield may stay in the room with their child. However, the technologist will always be able to see, hear and speak with you through a built-in intercom system.

With pediatric patients, a parent may be allowed in the room but may need to wear a lead apron to minimize radiation exposure. After a CT exam, the technologist will remove your intravenous line. They will cover the tiny hole made by the needle with a small dressing. You can return to your normal activities immediately.

A radiologist , a doctor specially trained to supervise and interpret radiology exams, will analyze the images.

The radiologist will send an official report to the doctor who ordered the exam. You may need a follow-up exam. If so, your doctor will explain why. Sometimes a follow-up exam further evaluates a potential issue with more views or a special imaging technique. It may also see if there has been any change in an issue over time.

Follow-up exams are often the best way to see if treatment is working or if a problem needs attention. A person who is very large may not fit into the opening of a conventional CT scanner.

Or, they may be over the weight limit—usually pounds—for the moving table. Compared to MR imaging, the precise details of soft tissue particularly the brain, including the disease processes are less visible on CT scans. CT is not sensitive in detecting inflammation of the meninges —the membranes covering the brain.

American Stroke Association: www. Please type your comment or suggestion into the text box below. Note: we are unable to answer specific questions or offer individual medical advice or opinions. Some imaging tests and treatments have special pediatric considerations. The teddy bear denotes child-specific content.

Please contact your physician with specific medical questions or for a referral to a radiologist or other physician. To locate a medical imaging or radiation oncology provider in your community, you can search the ACR-accredited facilities database.