What is a CT Scan?

Radiological examinations, which are used in the diagnosis of many diseases, are conducted by a radiologist, also known as a radiology specialist. CT (Computerized Tomography) is one of the most frequently used imaging techniques in the field of radiology. To understand what tomography means, we should first look at its definition. The word "tomography" is derived from the Greek word Tomos, meaning slice or section, and Graphein, meaning to write or record.

When your doctor orders a CT scan, the radiologist or radiology technician will take the tomography of the body part that needs to be examined. The radiologist will then prepare a detailed report based on the film and send it to the referring doctor. CT is a diagnostic tool that scans the relevant body area or areas in detail using X-ray rays to create a layered image. During the scan, it captures images of bones, soft tissues, organs, and vessels from different angles, allowing the creation of cross-sectional images.

Unlike X-rays, CT scans provide much more detailed, 3D images, which help doctors understand how to proceed with treatment and interventions. The radiology specialist moves the X-ray beams around the patient, who is lying still on a table, and combines the resulting images to produce a detailed cross-sectional view. The CT scan machine is a ring-shaped device with a hollow center, in which the patient lies on a table that moves into the machine. CT is often used for emergency diagnosis due to its rapid imaging capabilities.

How is a CT Scan performed?

When a CT scan is requested, the patient is directed to the area of the radiology department where the CT scanner is located. The patient should refrain from eating for about 6 hours and drinking water for at least 4 hours before the scan. In a changing room, the patient removes clothing or accessories in the area to be examined and wears a hospital gown. All metal objects, such as rings, glasses, dentures, and hairpins, must be removed. After the necessary instructions, the patient lies on the CT scanner's table. Depending on the area to be scanned, the patient may need to lie on their back or stomach.

The machine’s model can determine whether the table or the device moves. In most cases, the table is fixed, and the machine moves around the patient, but some models may involve movement of the table instead. The radiologist provides prior instructions about the procedure. Pillows and straps are used to help the patient stay comfortable and ensure the images are accurately captured. The patient remains alone in the room, but the radiologist can see, hear, and communicate with the patient during the process. It is crucial that the patient remains still during the scan to avoid image distortion. In some cases, the patient may be asked to hold their breath.

During the scan, the X-ray tube rotates around the patient, capturing several images, which are then combined by a computer to create a 3D image. The duration of the CT scan varies depending on the area being scanned but typically takes a few minutes to half an hour. After the scan, the patient can return to their daily activities without restrictions. In some cases, contrast-enhanced CT scans are performed.

What is Contrast-Enhanced CT?

A contrast-enhanced CT scan is used to obtain clearer and more detailed images. A contrast material, which is typically iodine or barium-based, is injected or taken orally to help enhance the clarity of the images. The patient's allergic history is checked before the contrast agent is administered. The contrast agent helps to make the image clearer, highlighting blockages or leaks in the body. While the experience of the procedure is the same as a regular CT scan, patients may feel a metallic taste in their mouth or warmth due to the contrast material. After the procedure, the patient is monitored by the radiologist for any reactions. In rare cases, patients may experience allergic reactions such as rash, itching, nausea, or redness.

Why is a CT Scan performed?

CT scans are diagnostic and imaging tools, not treatments. A doctor may recommend a CT scan to aid in diagnosis after listening to the patient's medical history and performing a physical exam. CT scans are used to evaluate potential injuries or trauma, such as brain damage or internal bleeding, and are commonly used for:

• Imaging internal organs in cases of injury or risk of internal bleeding
• Detecting bone fractures or tumors
• Imaging the sinuses around the nose (paranasal sinuses)
• Diagnosing suspected diseases in organs like the heart, brain, lungs, and liver
• Identifying the exact location of blood clots or tumors
• Measuring bone density
• Detecting bone pathologies and imaging the skeletal system
• Determining the stage of cancer and monitoring treatment effectiveness
• Detecting metastasis
• Visualizing the effectiveness of other treatments

Unlike MRI (Magnetic Resonance Imaging), CT scans are preferred because they provide 3D cross-sectional images. Brain and lung CT scans are some of the most commonly used medical imaging techniques.

How is a Brain CT Scan performed?

Brain CT scans are used to diagnose tumors, head injuries, strokes, brain hemorrhages, and other brain-related conditions. CT scans of the brain can be performed with or without contrast. If contrast is used, it is injected intravenously, providing more detailed images for better analysis. During the procedure, the patient may be asked to hold their breath at certain intervals.

What are the Advantages of CT Scanning?

The advantages of CT scanning include:

• Obtaining detailed, cross-sectional images
• Fast imaging process
• Quick differentiation between healthy and damaged tissues
• Enabling accurate treatment planning by preventing unnecessary interventions
• 3D imaging of vessels, tissues, bones, and organs
• Assisting doctors in confirming diagnoses and determining treatment plans

Don't neglect regular checkups for a healthy life.