Computed Tomography

Computed tomography is a radiological imaging technique that uses X-rays to produce cross-sectional images (slices) of internal organs and tissues. It is one of the leading imaging techniques in modern medicine, offering high diagnostic accuracy and excellent detail.

Unlike standard radiography, which produces a flat, two-dimensional image, CT prevents the overlap of anatomical structures. The computer processes many images taken from different angles and reconstructs them into detailed cross-sections. This process allows precise evaluation of the anatomy in the region of interest.

Principle and Technique

During the scan, the patient lies on a table that slowly moves through the ring-shaped part of the machine, called the gantry. Inside the gantry, an X-ray tube and a system of detectors rotate around the patient. The tube emits a narrow, fan-shaped X-ray beam, while detectors on the opposite side record the transmitted X-rays as they pass through the body.

The collected data are processed by a powerful computer, which reconstructs a three-dimensional model of the examined area using advanced mathematical algorithms (Radon transform). To enhance visualization of blood vessels and soft tissues, the scan may be performed with intravenous injection of an iodine-based contrast agent.

Clinical Significance

CT has a very wide range of applications in medicine because it is fast and highly detailed.

• Traumatology. The “gold standard” for diagnosing head injuries, spinal trauma, and internal organ damage.
• Oncology. CT is used to detect tumors, determine their stage (staging), and monitor treatment effectiveness.
• Vascular medicine. CT angiography provides detailed visualization of blood vessels and helps identify aneurysms, thrombosis, or atherosclerotic plaques.
• Neurology. CT is essential for diagnosing strokes, especially hemorrhagic ones, which are immediately visible on CT.

The main limitation of CT is the ionizing radiation dose received by the patient, so the scan is performed only when clinically indicated.