Why is tractography needed?
The method shows the course of the nerve tracts and their relationship with the pathological focus. This is critically important when planning a neurosurgical operation: the surgeon sees in advance where the motor and speech pathways are, and chooses an approach that minimally affects them. Tractography is also used to assess the consequences of traumatic brain injury and demyelinating diseases.
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.