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Computed Tomography (CT) Scan

Computed Tomography (CT) Scan

CT scans use x-ray equipment and computer processing to produce 2-dimensional images of the body. The patient lies on a table and passes through a machine that looks like a large, squared-off donut. Doctors order CT scans when they want to see a two-dimensional image of the body to look for tumors and examine lymph nodes and bone abnormalities. If contrast dye is used to improve the computer image, the patient may need to avoid eating or drinking for 4 to 6 hours before the test. Patients should tell their provider before the test if they have any allergies or kidney problems.

Specialty Services / Procedures

  • Angiography

    An angiography is an imaging test that uses x-rays to view the body’s blood vessels.

  • CT Enterography

    A CT Enterography is a special type of computed tomography (CT) imaging performed with intravenous contrast material after the ingestion of liquid that helps produce high resolution images of the small intestine in addition to the other structures in the abdomen and pelvis.

  • Virtual colonoscopy

    A virtual colonoscopy is a medical imaging procedure which uses x-rays and computers to produce two- and three-dimensional images of the colon (large intestine) from the lowest part, the rectum, all the way to the lower end of the small intestine and display them on a screen.

  • Biopsy

    Any suspicious mass of tissue or tumor is subject to a biopsy, or removal of cells from the mass. This is the only technique that can confirm the presence of cancer cells. The doctor will use a general or local anesthetic depending on the location of the mass, and then remove a sample of tissue to send to the lab. The sample is sent to a pathologist, a physician who is an expert at identifying diseased cells in tissue samples. Very often, a few stiches are used to help the area heal, and tenderness is felt for a short period of time.

  • Radiofrequency Ablation for Cancer

    Radiofrequency ablation (RFA) is a cancer treatment in which radiofrequency energy—derived from electric and magnetic energy—is sent by means of a narrow probe that is placed in the center of a lung tumor. Surgical incisions are not required, and the probes are placed into tumors using CT scan to guide the physician. RFA is a newer method of treating lung cancer, as well as cancers of the liver, kidney, and bone. RFA can target and kill cancerous cells sparing healthy tissues that are close to the cancer. Systemic treatments such as chemotherapy and certain types of radiation are absorbed into both healthy and diseased tissue, whereas RFA is delivered directly into a tumor.

  • Implant Fiducial Markers for Cancer Treatment
  • Pediatric exams with and without conscious sedation

What Can I Expect Before My Exam?

When you arrive in Radiology, you will be registered by a member of our Patient Access Services team and then be greeted by a CT Technologist, who will explain your specific exam to you. You will be asked to complete a contrast history form and answer questions about any medications you may be taking. Please bring a list of your current medications with you to your appointment. Based on your medical history and/or physician request, the length of your exam may vary from approximately a ½ hour to approximately 2 hours.

Some exams require oral contrast. In this case, the technologist will administer the oral contrast and explain the process for this exam to you. The technologists need to wait approximately an hour and a half for the oral contrast to work its way through your intestines before they can begin imaging. For these exams, please plan to spend approximately 2 hours in the department.

Many exams also require IV contrast. If this is the case and you do not need oral contrast, the technologist will take you to the scanner area to prepare you for your imaging exam.

What Can I Expect During My Exam?

You will be asked to lie down on the CT scanner table - either on your back or your stomach - and the technologist will monitor you the entire time. You may be asked to hold your breath for certain parts of the scan; it is very important you hold still so that your pictures are clear. The table will move in and out of the tube, capturing “slices” or pictures of the area.

The entire scan lasts about 15 minutes. Once the scan is completed, the technologist will review the images to make sure the scan is complete. Then, they will bring you out of the room and remove your IV if necessary.

What Can I Expect After My Exam?

Once the test is completed you can resume normal daily activities. If you received IV contrast, we ask that you drink plenty of water for the next 24 hours to help flush it out. If you drank oral contrast, you might notice that your stools appear white for about one day after the test. This is completely normal.

When Can I Expect My Results?

Once the radiologist reads your images, your ordering physician will receive your results typically within 24 to 48 hours. Your physician will go over the findings with you.

To obtain copies of your images, please call the film library at 617.414.5882.