CT Scan

CT Scan

What is a CT scanner?

A CT (computerized tomography) scanner is a specialized type of X-ray machine. Unlike conventional X-rays that emit a single beam through your body, multiple beams are simultaneously directed from different angles during a CT scan.

How does a CT scanner function?

After passing through the body, the X-rays from these beams are detected and their intensity is measured. Beams that traverse less dense tissues like the lungs appear stronger, while those traversing denser tissues like bone appear weaker. Utilizing this data, a computer determines the relative density of examined tissues.

Each scan essentially produces a cross-sectional view of the body. The computer processes these results, presenting them as two-dimensional images on a monitor. Sir Godfrey Hounsfield, a British inventor, pioneered the CT scanning technique and was awarded the Nobel Prize for his contributions.

What are CT scans utilized for?

CT scans offer significantly more detailed images than conventional X-rays. Modern CT scanners can reconstruct two-dimensional computer images into three-dimensional renderings, providing virtual views akin to what a surgeon might observe during an operation. These scans have revolutionized medical diagnostics, enabling non-invasive exploration of internal structures. They are invaluable for identifying tumors and planning radiotherapy treatment.

How is a CT scan conducted?

Originally designed for brain imaging, CT scanners have evolved to encompass virtually any body part. They excel in detecting brain bleeding, aneurysms, tumors, and injuries throughout the body. Additionally, they aid in diagnosing lung diseases and internal injuries like kidney or liver tears, as well as guiding biopsies and pain-relieving procedures.

How is a CT scan prepared for?

Before an abdominal scan, patients typically fast for six hours and drink a gastrografin solution—an aniseed-flavored X-ray dye—to enhance bowel visibility. Sometimes, a liquid X-ray dye is injected into veins during the test to improve organ visualization. While slightly uncomfortable, this injection may cause warmth in the arm.

How is a CT scan performed?

The scanner resembles a large doughnut. During the scan, the patient lies on a bed with the examined body part positioned within the scanner's circular opening. The bed moves slowly to facilitate imaging, but does not touch the patient. The duration of the test varies based on the number and angles of images taken.

Does a CT scan cause discomfort?

The procedure itself is painless, but some individuals find it uncomfortable lying in the scanner's tunnel. Severe claustrophobia may pose challenges for some patients during CT scans. Informing doctors and radiographers beforehand can help address such concerns.

Is a CT scan risky?

Due to the increased X-ray exposure compared to conventional X-rays, CT scans are only recommended when medically necessary. Allergic reactions to the injected dye may occur in some patients, with rare instances of kidney damage in those with pre-existing kidney conditions.

How is a CT scan interpreted?

CT scans provide doctors with detailed internal views of the body, showcasing various tissues like bone, muscle, and fatty tissue. For abdominal scans, organs such as the pancreas, spleen, and liver are clearly delineated. Brain scans reveal detailed structures like the ventricles.

Additionally, CT scans can detect minute lung abnormalities, with ongoing research exploring their potential in lung cancer screening.