What is CT Scan (Computed Tomography): Meaning, Working & Procedure

A CT (computerised tomography) scan is a modern version of a CAT (computerised axial tomography) scan. It advances conventional x-ray procedures to understand one's internal issues better. Thus, healthcare professionals suggest a CT scan to evaluate a patient's internal conditions.

This article highlights what a CT scan is, how it works, and the medical procedure professionals follow. So, read on to learn more!

Computed Tomography scan is a computerised x-ray scanning of a body from different angles. It allows a doctor to see through the blood vessels, bones and soft tissues with cross-sectional images or ‘slices’. So, it provides a more detailed view of the insides than conventional x-rays.

As a result, a CT scan can pinpoint abnormalities like injuries, tumours, blood clots or any unnatural presence in the body. Thus, physicians prescribe scanning to visualise different regions of the body, such as:

• Heart
• Head
• Shoulders
• Chest, etc.

Though x-rays and ultrasounds give adequate information, Computed Tomography is essential for more detailed insight.

During a CT scan, ionising radiation rotates around the body through the gantry. The gantry is the circular part of a CT scanner that plays a crucial role in producing and detecting rays. Each time the radiation moves throughout the body, it captures an abundance of images or slices. They can be displayed partially or "stacked", depending on the requirements.

These Tomography images are often stacked with each other to create a three-dimensional (3D) view of the internal structure of an individual. Physicians detect abnormalities by studying these 3D images of organs, tissues, skeletons and other parts.

The following are the different uses of CT scans:

• Locating tumours, pulmonary embolisms (blood clots), infections, injuries or excess fluid.
• Identifying heart diseases, cancer, emphysema or pneumonia, and liver diseases.
• Detecting bone fractures, tumours, eroded joints, muscle or other bone disorders.
• Assessing for procedures like biopsies, surgeries, and radiation therapy.
• Monitoring treatment programmes related to chemotherapy or radiation.
• Detecting internal bleeding, haemorrhage, and other health conditions.

In case you want to run a CT scan for any of the above issues, a radiology expert will execute the scanning and make the report. So later, after thoroughly assessing the tomography report, doctors can decide on further treatment.

A CT scan takes only a little time. Moreover, professionals may carry it with or without contrast depending on the health condition. Contrast is a dye containing barium or iodine to enhance the contrast level and resolution of the slices or images.

The preparation one needs to go through before scanning is as follows:

• The clinician will provide contrast orally or through injection to prepare for the test.
• A patient should not eat solid foods for 4 hours before scanning.
• Patients need to remove any metallic object or medical devices from the body, like jewellery, watches, hearing aids etc.

The entire process could take 20 minutes to 1 hour. Also, it is crucial to stay still to avoid blurry test reports. Moreover, further treatment or tests will be required if the doctor notices any unnatural characteristics.

Although the radiation is mild for most people, some can experience few side effects of a CT scan. For example, getting allergic symptoms like rashes or itchiness from the contrast. In addition, some may feel catastrophic in a few cases. Hence, communication with the physician is advisable about pre-existing medication. So, convey if you have iodine or seafood allergies before the test.

Additionally, let the doctor know if you take any medication for kidney or diabetes. The doctor may suggest refraining from the medication before or after the process.

CT scan is a process of diagnosing critical problems like cancer, blood clots, haemorrhage and more. So, if the process takes place on time, it can save lives. Yet, ionising radiation can impact living tissues. However, this risk of a CT scan is minor compared to the existing life-threatening condition.

Other risks of CT scan you must watch out for include:

• Risk of cancer from frequent scans
• Harmful effect on unborn babies
  

Frequent or multiple CT scans can expose individuals to a lot of risks from radiation. Therefore, patients or parents can ask for other alternatives to prevent further damage. The cases where you can ask for alternatives include:

• Children are more at risk of developing cancer from radiation than adults. Therefore, parents should consult the radiologist or physician beforehand for children-friendly manual radiation adjustment. In contrast, parents can also ask for a diagnosis process without ionising radiation, such as magnetic resonance imaging (MRI).
• A CT scan exerts potential risks on unborn babies. So, if the mother needs tomography images of the abdomen or pelvis, the doctor prescribes tests like ultrasound.

After the scan, the patient can return to everyday life. However, the patient may need to stay longer if contrast is used. Moreover, physicians may instruct to wait at the clinic to check for any allergic reaction to the contrast.

From the above information, we can extract that a CT scan is crucial in diagnosing an underlying disease or injury. However, in real-case scenarios, people can get anxious while having unidentified critical issues. Thus, one must make sure to read about what is a CT scan or how it occurs before the procedure.