Microscopy and Culture

Microscopy and Culture

What is magnetic resonance imaging (MRI)?

Magnetic resonance imaging (MRI) is a relatively recent technology introduced since the early 1980s.

MRI employs magnetic and radio waves, eliminating the need for exposure to X-rays or other harmful radiation.

How does an MRI scanner operate?

The patient is positioned within a large, cylindrical magnet.

Radio waves, much stronger than the Earth's magnetic field, are transmitted through the body, altering the positioning of the body's atoms, particularly the hydrogen nuclei.

As these nuclei return to their original state, they emit radio waves of their own.

The scanner detects these signals, converting them into detailed images with the assistance of a computer. These images are generated based on the location and intensity of the received signals.

Since the human body is primarily composed of water, which contains hydrogen atoms, the hydrogen nucleus is often utilized to produce an MRI image through the described process.

What can an MRI scan reveal?

MRI scanning can produce images of nearly all tissues within the body.

Tissues with fewer hydrogen atoms, like bones, appear dark, while those with abundant hydrogen atoms, such as fatty tissue, appear brighter.

By adjusting the timing of radio wave pulses, valuable information about various tissue types can be obtained.

MRI scans are particularly useful for examining parts of the body surrounded by bone tissue, such as the brain and spinal cord.

The detailed images provided by MRI scans make them highly effective in detecting brain tumors (both benign and malignant), assessing their spread into nearby tissues, and identifying other brain abnormalities like those associated with multiple sclerosis or stroke.

MRI scans also allow visualization of the heart, major blood vessels, joints, spine, and certain soft tissues like the liver, kidneys, and spleen.

How does an MRI scan differ from a CT scan?

Unlike CT scans, which typically provide horizontal images, MRI scans offer images from various angles.

Moreover, MRI scans do not involve ionizing radiation (X-rays) and generally produce more detailed images, facilitating clearer differentiation between normal and abnormal tissues.

How is an MRI scan conducted?

MRI scans are typically outpatient procedures, allowing patients to return home afterward. Patients must remain completely still during the scan, which may necessitate anesthesia for children.

Due to the powerful magnetic field involved, patients must remove all jewelry and metallic objects. While orthopedic metal implants usually pose no issues, certain electronic devices or metal implants like pacemakers are contraindicated.

Is an MRI scan risky?

MRI scans are considered safe, with no known dangers or side effects. The procedure is painless and repeatable, as it does not involve radiation.

However, there's a theoretical risk to the fetus during the first trimester of pregnancy, so MRI scans are avoided during this period.

Some individuals may experience claustrophobia or discomfort due to the enclosed space of the MRI machine and the loud banging noises it produces during operation. In such cases, patients can discuss potential solutions, including medication for relaxation, with their doctor beforehand.