What adds contrast
Contrast enhancement helps to distinguish a tumor from an inflammatory infiltrate, see necrosis inside the formation, assess the condition of regional lymph nodes and determine whether the process is growing into the vessels. This is the standard for oncological searches in the head and neck area and in preparation for surgery, when the surgeon needs to accurately understand the boundaries of the intervention.
What is MRI and how does it differ from CT
Magnetic resonance imaging uses a strong magnetic field and radiofrequency pulses to create images—without X-rays. The method is especially informative for soft tissues: the brain and spinal cord, ligaments, cartilage, muscles, and pelvic organs.
CT scans show better bones, light and acute hemorrhages and are completed in seconds. MRI wins where detailing soft tissues is important: disc herniation, brain tumor, meniscus tear, pituitary gland pathology.
When contrast is needed
A gadolinium-based contrast agent is administered intravenously and accumulates in areas with increased blood flow. This allows you to distinguish a tumor from edema, see the boundaries of the formation, assess the activity of inflammation and detect small metastases.
Not everyone is prescribed contrast: for most studies of the spine, joints and brain without suspicion of a tumor, it is not required. Before administration, it is important to know the creatinine level in case of kidney disease.
Contraindications
- pacemaker and other active implants
- ferromagnetic clips on brain vessels
- metal foreign bodies in the orbit
- first trimester of pregnancy - according to strict indications
- severe claustrophobia - requires preparation or sedation
How the research works
The main condition for a high-quality photograph is stillness. Any movement blurs the image, and the series has to be repeated. The patient holds a button to communicate with the operator, and through the microphone you can talk to the doctor at any time.