CT & MRI SCANS
How does a computed tomography scan work?
Computed Tomography (CT), also known as a CT scan, is a diagnostic imaging technique
that uses X-rays to obtain detailed images of the inside of the body. Unlike a conventional
X-ray, which provides a flat image, a CT scan captures multiple images from different angles
around the patient. These images are processed by a computer to create cross-sectional
views (like slices) of the body, allowing for a more precise visualization of internal structures.
During the procedure, the patient lies on a table that slowly moves through a large
ring-shaped machine called a gantry. Inside this ring, an X-ray tube rotates around the body
while special detectors collect the radiation that passes through the tissues. Using advanced
computer algorithms, these signals are transformed into detailed images of organs, bones,
blood vessels, and other structures.
CT scans are especially useful for diagnosing fractures, tumors, infections, internal bleeding,
and evaluating brain or lung injuries. Although it is a fast and accurate technique, it involves
exposure to ionizing radiation, so it is used cautiously, particularly in children and pregnant
women.
How does a magnetic resonance imaging scan work?
Magnetic Resonance Imaging (MRI) is a medical imaging technique that uses strong
magnetic fields and radio waves to create detailed images of the inside of the body. Unlike
CT scans or X-rays, MRI does not use ionizing radiation, making it a safer option for
repeated imaging or for use in vulnerable populations like children and pregnant women.
During an MRI scan, the patient lies on a table that slides into a large cylindrical machine.
Inside the scanner, a powerful magnet aligns the hydrogen atoms in the body's water and fat
molecules. When short bursts of radio waves are sent through the body, these aligned atoms
are temporarily disturbed. As the atoms return to their original positions, they emit signals
that are detected by the machine and processed by a computer to generate high-resolution
images of tissues and organs.
MRI is especially valuable for imaging soft tissues such as the brain, spinal cord, muscles,
ligaments, and internal organs. It can detect abnormalities like tumors, inflammation, nerve
damage, or joint injuries with exceptional clarity. However, MRI scans take longer than CT
scans, and the patient must remain very still throughout the procedure to avoid blurring.
