What is a CT Scan or CAT Scan?

A CT scan uses a technique that combines X-rays to create a cross-sectional view of your body. You may hear a CT Scan called a CAT Scan.

What Does CT Stand For?

CT ScanCT stands for “computed tomography.” Tomography comes from the Greek word tomos meaning “slice.” Tomography refers to any form of imaging displaying a cross-section through the body or object using either X-ray or other technologies. Computed tomography is combining the X-ray features with computer technology in order to create highly detailed images or slices that physicians use to diagnose and treat patients.

How Do CT Scans Work?

CT scans are extremely beneficial because they allow medical professionals to see into the interior of the body without making incisions. This technology was not available 40 years ago which led to a lot of invasive, exploratory procedures that may or may not have yielded conclusive results.

CT scans use the power of X-rays and computer software in order to create medical images. The equipment looks like a large circular chamber with a bed inside. You’ll lie down and are then slowly moved inside the circular chamber or “gantry.” The that you are lying on will move you in and out of the gantry. The interior of the chamber is equipped with video and microphone so CT technicians and doctors can still hear and see you.

CT scans do not take too much time, at most 30-45 minutes. It is very important for patients to remain as still as possible in order to produce the clearest images. Inside the CT’s opening, on one side there is an X-ray tube that emits X-rays and on the other side of the circle is a large detector. As the machine makes an entire rotation,  X-rays move through the body and are caught by the detector. The detector captures the X-rays as one “slice” or angle and transfers them to computer software that translates the image.

What are CT scans used for?

What a CT scan searching for in the body is dependent on what the patient needs. Doctors use CTs for a number of reasons: broken bones, cardiovascular problems, blood clots, bleeding, cancer detection and much more. At Doctors Imaging in Metairie, our CT machine ensures a thorough examination for patients and accurate diagnosis for doctors.

If you have more questions about what a CT scan is, what to do to prepare for your CT or what to expect, you can visit our CT Services Page. If you would like to schedule a CT appointment you can do so through our Request an Appointment page or you can call our offices at 504-883-8111 Monday through Friday 8:00am until 5:00pm.

Learn More About CT Scans and CAT Scans

What Happens During a Chest CT Scan?

From RadiologyInfo.org

What is the difference between a CT and a PET-CT scan?


CT and PET-CT scans are very common procedures that doctors administer every day to help localize their examination and to provide the most thorough diagnosis. Both procedures contain varying, minimal risks but can provide huge benefits for patients that need a more in-depth examination and specialized treatment.

What is a CT scan?

A CT scan or a Computed Tomography scan is a medical procedure that uses x-ray radiation and fascinating computer technology to create cross-sectional images of the body’s organs and tissues. CT scans can also be called CAT or Computed Axial Tomography. CT scans take helical images of the examined part of the body which produces better 3-dimensional imaging. The better the image, the better the diagnosis your doctor can make. CT scans are particularly useful in the examination of tissues, cancer staging, and determining vascular disease.

What is a PET-CT scan?

A PET-CT scan or Positron Emission Tomography is a medical procedure similar to a CT scan but PET-CT scans are commonly used in determining the difference between healthy and diseased tissue. Using nuclear medicine these exams allow particular focus on oncological symptoms in the brain and heart as well as any vascular or tissue abnormalities.

What are the procedures like?

The biggest difference between a CT and a PET-CT scan is the machinations of the procedure. There are varying states of discomfort between both procedures, but both are relatively painless and easy to complete for any patient.

A CT machine looks like a large tire with the patient placed inside the “hole.” The patient is placed on the examination table and will be administered contrast material through the mouth or intravenously. The feet will be the first to enter into the machine and the body will be slowly moved into the chamber. The procedure lasts approximately 10-30 minutes. Patients typically report that they hear a slight whirring sound which is the machine rotating around them gathering imaging. The doctor will able to speak to you and you will be able to respond.

A PET-CT scan is similar to a CT scan in some ways but the biggest difference between the two is the instructions prior to the exam. Most doctors and facilities will request that a patient not eat at least 4 hours prior to the scan and to drink lots of water. The exam also lasts slightly longer at about 30-45 minutes. Contrast material is commonly used as well and will either be  administered through an IV or by inhalation. If the PET-CT scan is being administered because of possible heart disease, the patient will often be asked to perform a stress test. The body will be examined at rest and during exercise in efforts to determine any cardiovascular problems. You may also hear a buzzing or clicking sound during this procedure.

Which procedure is more painful?

Both procedures have a minimal amount of pain and discomfort. The most common complaint is concerning the IV injection site or a claustrophobic feeling. But the contrast material is necessary for properly determining the condition of tissues and veins as well as highlighting possible cancerous cells. Furthermore, the body moves through the machine. It only covers the area that will be examined — it does not encapsulate the entire body.

Are there any risks?

Doctors and imaging facilities have been able to minimize the risks surrounding these procedures to practically nothing. Both a CT and PET-CT scan use small amounts of radiation to image the examined area. If you are pregnant or could possibly be pregnant, you should let your doctor know. There is no medical evidence that the amount of radiation is dangerous for an unborn child. But if there is another safer method to examine, your doctor can help you understand your options. Also if you have any implanted devices, artificial body parts or features such as hearing aids or dentures, talk to your doctor about what needs to removed for the procedure.

Ready to make your appointment? You can use our request an appointment form online or just call us at 504-883-8111.

The History of Medical Imaging

The first X-RayMedical imaging is a form of technology that has revolutionized the medical field in the past century.  With these new innovations, doctors were able to elevate the standard of practice and the experience of the patient. Now, areas of pain or trouble can be non-invasively examined and treatment can begin without the patient even needing to go under. But when did the innovation of medical imaging begin?

Read below to take a trip down memory lane and find out how the medical field and the technology industry have been working together to build a better, healthier world.

Röntgen performs X-Ray in 1895

Professor Wilhelm Röntgen accidentally discovers the ability to look through the skin and see the bones of the body while performing experiments on another project. While working with a cathode ray generator, he noticed an image that was left when the cathode rays came into contact with the vacuum tube. He performed the first X-ray on his wife’s hand and even gave the technology the name we use today, calling this discovery “X” rays because they were unsure what exactly they were. This invention was eventually standardized by William Coolidge and his X-ray known as the “Coolidge tube” is what all modern X-ray machines are based from.  The first X-rays required at least 11 minutes of exposure to produce a quality image. Now X-rays take only a few seconds and they use about 2% of the radiation amount seen in the early 20th century machines.

Scientists Use Ultrasounds in the 1960s

The basics of sonar had been discovered and utilized during World War II as a form of maritime warfare. In the early 1960s, scientists discovered that sending sound waves into the body would bounce off the internal structures and then returned to the ultrasound machine to be reformatted into images for doctors to see. This allowed doctors to non-invasively search for tumors and other growths.

Damadian Discovers MRI in 1970

Dr. Raymond Damadian discovers that different animal tissues emit different signals, as well as that cancerous tissues, take much longer to return the signal sent through them. This is the basis for magnetic resonance imaging. In 1977, Dr. Damadian created the first full-body MRI machine which he named the “Indomitable.”

Hounsfield Invents CT Scans in 1972

The 1970s showed the first instance of computer technology mixing into the medical field with Sir Godfrey Hounsfield’s invention of the CT machine. He theorizes that you could see into an object if you took X-rays from different angles of the object through a machine that would appear as “slices” which could then be put together to form an image. With his idea, he formed the first “axial tomography” machine which we now know as the CT machine. In 1979, he received the Nobel Prize in Medicine and was later knighted by the British Royal Family.

Since then, all of these machines have entered into the digital age and are now updated with the latest technology available. This means that there is less potential risk for patients as well as a greater ability to diagnose and treat.

Looking for medical imaging in Louisiana? At Doctors Imaging, we’re Radiologists concerned with patient care. Meet our Radiologists or request your next medical impaging appointment online.