Types of CT Scans

New Jersey CAT Scans

A CT scan can be used to examine many parts of the body. The specifics of your procedure at Atlantic Medical Imaging may vary depending on what the doctor is looking for and your current medical condition. Below, we outline some of the basics of various CT scan procedures.

Several types of low dose CT scans are offered at Atlantic Medical Imaging in New Jersey including:

• CT Scan Abdomen
• CT Angiography
• CT Scan Arthrography
• CT Scan Bones
• CT Scan Brain/ CT Scan Head
• CT Scan Chest (CT Scan Lung)
• CT Scan Neck
• CT Scan Pelvis
• CT Scan Renal Stones
• CT Scan Sinus
• CT Scan Spine

Below is a brief overview of each CT service.

CT Scan Abdomen

CT imaging of the abdomen is an examination that uses x-rays to visualize several types of tissue, including organs such as the liver, spleen, pancreas, and kidneys. Using specialized equipment and expertise to create and interpret CT scans of the lower gastrointestinal (GI) tract, colon, and rectum, an experienced radiologist can accurately diagnose many causes of abdominal pain, such as:

• An abscess in the abdomen
• Inflamed colon
• Colon cancer
• Diverticulitis
• Appendicitis

Often, no additional diagnostic work-up is necessary and treatment planning can begin immediately.

CT is often the preferred method for diagnosing many different cancers, including colon cancer, since the image allows a physician to confirm the presence of a tumor and to measure its size, precise location, and the extent of the tumor's involvement with other nearby tissue. CT examinations of the lower GI tract can be used to plan and properly administer radiation treatments for tumors, and to guide biopsies and other minimally invasive procedures. CT can also play a significant role in the detection, diagnosis, and treatment of vascular disorders that can lead to stroke, gangrene, or kidney failure.

A CT examination of the gastrointestinal tract requires the use of a contrast material to enhance the visibility of certain tissues. Before administering the contrast material, the radiologist or technologist will ask whether you have any allergies, especially to medications or iodine, and whether you have a history of diabetes, asthma, a heart condition, kidney problems 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.

A CT examination usually takes from five minutes to half an hour. When the exam is over, the patient may be asked to wait until the images are examined to determine if more images are needed.

CT Angiography (CT Angiogram)

CT scans can be used to assess a patient’s risk for heart disease in a procedure known as CT Angiography (CTA). Atlantic Medical Imaging was the first imaging practice in the area to offer the highly esteemed Coronary CTA procedure. In this imaging test, a contrast dye is injected into the arteries. The CT scanner then takes x-rays to create an image of blood flow in the body, which should be highlighted thanks to the contrast dye.

CT Angiography can detect signs of heart disease in the earliest stages. With this procedure, we can assess how efficiently blood is flowing in both the coronary and peripheral vascular system.

CTA is commonly used to:

• Detect signs of heart disease and atherosclerosis
• Examine pulmonary arteries to diagnose or rule out a pulmonary embolism
• Assess blood flow in the renal arteries
• Diagnose aneurysms
• Look for warning signs of a heart attack or stroke
• Assess heart health and blood flow after cardiovascular surgery

CTAs only take a few seconds. Most of the time you spend at the office will be spent setting things up. After changing into a gown and having an IV set up, you will answer questions about things that might complicate the exam (such as allergies) and then will lie down on a narrow table. A sample of contrast dye will be injected to see how quickly it can reach the designated area. The IV is then hooked up to an automatic injector, contrast material is injected, and the scan begins.

A CTA typically lasts between 10 to 25 minutes. Overall, you can expect to be in or near the examining room for 20 to 30 minutes. The test should not be painful. Once the needed images have been recorded, you will be free to leave. You can eat immediately after and it is recommended you drink plenty of water to flush the contrast dye out of your system.

CT Scan Chest

CT scanning of the chest uses special equipment to obtain multiple cross-sectional images of the organs and tissues of the chest. CT produces images that are far more detailed than a conventional chest x-ray and is especially useful because it can simultaneously show many different types of tissue including the lungs, heart, bones, soft tissues, muscle, and blood vessels.

Chest CT also can be used to diagnose various lung disorders such as:

• Old or new pneumonia
• Lung cancer
• Tumors
• Tuberculosis
• Emphysema
• Bronchiectasis
• Diffuse interstitial lung disease

Additionally, accident victims and other people with chest injury often have a CT exam to assess damage to organs, bones (including the spinal column), and to large blood vessels.

When the clinical findings and regular chest x-ray are inconclusive, CT may clarify the situation. Inflammation or other diseases of the pleura, the membrane covering the lungs, can be seen in CT images.

CT scanning is a pain-free procedure. If contrast material is injected, you may feel a flush of heat or a metallic taste in your mouth, usually lasting no more than a minute or two. You also may notice mild itching. If this persists or hives develop, effective medication is available. Very rarely a patient becomes short of breath or has swelling in the throat or another part of the body, indicating a more serious reaction to contrast material that must be promptly treated. If you experience any of these symptoms, inform the technologist immediately.

You will be alone during the scan, but the technologist can see and hear you and can speak to you at any time from the adjacent control room. The examination usually takes 15 to 30 minutes, including preparation time. The actual scan time is less than 30 seconds.

CT Scan Head (CT Scan Brain)

CT scanning of the head is an examination that provides detailed information on head injuries, brain tumors, and other brain diseases. It also can show bone, soft tissues, and blood vessels in the same images.

CT of the head can assist in:

• Locating skull fractures and brain damage in patients with head injuries
• Detecting a blood clot or bleeding within the brain shortly after a patient exhibits symptoms of a stroke
• Determining the extent of bone and soft tissue damage in patients with facial trauma, and planning surgical reconstruction
• Detecting and localizing bleeding in a patient with sudden severe headache who may have a ruptured or leaking aneurysm
• Detecting some brain tumors
• Diagnosing diseases of the temporal bone on the side of the skull, which may cause hearing problems
• Illuminating enlarged brain cavities (ventricles) in patients with hydrocephalus
• Determining whether inflammation or other changes are present in the paranasal sinuses
• Planning radiation therapy for cancer of the brain or other tissues
• Guiding the passage of a needle used to obtain a tissue sample (biopsy) from the brain
• Non-invasively assessing for aneurysms or arteriovenous malformations through a technique called CT angiography
• Detecting diseases or malformations of the skull
• Three-dimensional imaging of the skull and brain structures

CT scanning of the head may be performed in the hospital or at an outpatient radiology center, but in either case your doctor must give you a written referral with the reason why the study should be performed. You will lie on a table that is guided into the center of the scanner, and you will be asked to lie very still.

As stated earlier, some patients will require an injection of a contrast material to enhance the visibility of certain tissues or blood vessels. A small needle connected to an intravenous line is placed in an arm or hand vein. The contrast material will be injected through this line. The CT scan itself should cause no pain.

Depending on the number of images needed, a CT exam of the head and brain can take between two and 45 minutes. When it is completed you will be asked to wait until the technologist examines the images to determine if more are needed.

CT Scan Spine

CT scanning of the spine is a type of x-ray examination that uses a scanner to obtain multiple images of the spinal column, as well as three-dimensional images if needed. CT images are far more detailed than those obtained by a conventional x-ray unit. In addition, CT is a very useful diagnostic method because it can display and distinguish many different types of tissue in the same region, including bone, muscle, soft tissue and blood vessels. The bony structure of the spinal vertebrae is clearly and accurately shown by CT scanning, as are the intervertebral disks and, to some degree, the spinal cord.

Some of the common uses of the procedure include:

• To detect or rule out spinal damage in patients who have been injured.
• The spine before and after surgery.
• To detect various types of tumors in the vertebral column, including those that have spread there from another area of the body. Some tumors that arise elsewhere are first identified by finding deposits of malignant cells (metastases) in the vertebrae; prostate cancer is an example.
• To detect narrowing of the spinal canal, vertebral fracture, infection, or degenerative disease such as arthritis, CT of the spine may provide important information when carried out by itself or in addition to magnetic resonance imaging (MRI). One of the most common causes of spinal pain that may be diagnosed by CT is a herniated intervertebral disk.

Spinal CT scanning is carried out with the patient lying on his or her back. The technologist will make sure that you are properly positioned, and may use pillows to help you maintain a correct posture during the study. If indicated, a contrast material will be injected into an arm vein during the procedure so as to sharpen the images of various tissues. A scan of the lower spine may also be done after injecting contrast material into the spinal canal surrounding the spinal cord during a lumbar puncture. This will help to detect tumors or locate areas of inflammation or nerve compression.

The actual imaging takes only a very short time and a complete exam, including set-up time, takes from five to 30 minutes. When the exam is completed, you may have to wait a short time while the radiologist checks the images to be sure that they are of high enough quality to be correctly interpreted. If necessary, a few additional scans will be obtained. Less patient movement during the procedure produces clearer CT images.

Spinal CT scanning is a painless procedure, apart from a needle stick if an intravenous injection is needed. Discomfort comes mainly from having to lie still on the table for some time. Injection of contrast material may cause a slight burning feeling in the arm, a metallic taste, and warm flushing of the entire body. These all are normal reactions and usually end within a few seconds.

Risks

• CT does involve exposure to radiation in the form of x-ray, but the benefit of an accurate diagnosis far outweighs the risk.
• Special care is taken during x-ray examinations to ensure maximum safety for the patient by shielding the abdomen and pelvis with a lead apron, with the exception of those examinations in which the abdomen and pelvis are being imaged. Women should always inform their doctor or x-ray technologist if there is any possibility that they are pregnant.
• Nursing mothers should wait for 24 hours after contrast material injection before resuming breast feeding.
• There is a risk of an allergic reaction which may be serious whenever contrast material containing iodine is injected. If you have a history of allergy to x-ray dye, your radiologist may advise that you take special medication for 24 hours before the exam to lessen the risk of allergic reaction. Another option is to undergo a different exam that does not call for contrast injection.
• Contrast injection should be avoided in patients with kidney disease or severe diabetes because x-ray contrast material can further harm kidney function.
• If a large amount of x-ray contrast leaks out under the skin where the IV is placed, skin damage can result. If you feel any pain in this area during contrast injection, you should immediately inform the technologist.