February 4, 2023
February 4, 2023

An introduction to Computerized tomography (CT)

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An introduction to Computerized tomography (CT)

Based on an interview with Dr. Charles Fiske, On-Site Radiologist and Medical Director, NorCal Imaging Walnut Creek

Computerized tomography (CT) is a common imaging technique that many patients will experience at some point.

How CTs work

CTs use X-rays to create cross-sectional images of the body with a scanner that runs the circumference of the body. These 2-D images are then stacked together to generate a 3-D image of the body from multiple angles.

Uses of CTs

CTs can be used to image any part of the body. Generally, they are used for any structure in the body and for imaging the bowel and lung – areas where motion is problematic for MRI. CTs are usually less prone to artifact, which may obscure or simulate pathology.

Prepping for CTs

There is generally no prep needed for a CT exam.

Radiation considerations for CTs

Radiation exposure can lead to radiation-induced neoplasms, which are a possible risk with CT scans. Physicians are constantly learning more about this risk. Radiation exposure can be more of a concern if a patient has two CT scans a year. In some cases, that is well within the standard of care for certain malignancies; for example, with soft tissue tumors such as sarcoma-type cancers where the patient is monitored over time with frequent repeated imaging. The benefits of the information should outweigh the risks associated with radiation.

Use of contrast

Most CTs can be done without the use of contrast; however, there are some cases where contrast (because it reflects blood flow and vascularity) may be needed. If a contrast dye is needed, an iodine-based agent is used.

Contrast is usually considered safe, has no immediate side effects in all but a few cases, and does not have long-term effects of significant consequence. A very small number of patients are allergic to iodine contrast, but such individuals represent a very small proportion of the patient population.

How medical providers decide what to order

Medical providers can order CTs based on a combination of their knowledge and experience, clinical guidelines and standard operating protocols, and informed clinical decision making with the patient.

Receiving and interpreting results

Imaging results are interpreted by a radiologist, and the report goes back to the ordering physician. Imaging reports tend to be full of medical jargon which may be difficult for patients to understand. However, this is changing with patient demand as patients increasingly want to understand their results themselves.

Today, there is an increasing shift toward creating reports that are simple for the patient to read and understand for themselves. The traditional pathway of interpreting the result by the radiologist and sending it to the referring doctor then having the doctor send it to the patient is changing in many ways.

This is where patient-oriented solutions like Ezra come in. Ezra’s focus on having the patient be a participant in their healthcare by understanding how the imaging fits into the big picture empowers patients to participate in their own care.

“It is increasingly clear that patients are willing to pay out of pocket to get an Ezra Scan with extra interpretation, detailed data, and longitudinal tracking of their health metrics. This shift benefits everyone. The better educated patients are about the disease processes they have and the information that imaging provides, the better-equipped they are to understand the disease processes and to be active participants in their well-being and care,” says Dr. Fiske.