What Is a Brain MRI Without Contrast?

Craniocerebral MRI is an MRI examination of the brain to observe whether there are lesions in the brain. It can be clear whether the patient is caused by changes in the brain structure. Intracranial tumors often cause epilepsy. The diagnosis of cell tumors, ganglia, gliomas, arteriovenous malformations, and hematomas is extremely high.

Craniocerebral MRI is an MRI examination of the brain to observe whether there are lesions in the brain. It can determine whether the patient is caused by changes in the brain structure. Intracranial tumors often cause epilepsy. MRI has low astrocytes in the brain. The diagnosis of cell tumors, ganglia, gliomas, arteriovenous malformations, and hematomas is extremely high.

Name: Cranial MRI

category: Magnetic resonance imaging

Normal MRI of the brain

Normal brain tissue has clear boundaries of gray matter and white matter on MRI images. The white matter signal is higher than gray matter on T1WI, and the gray matter signal is higher than white matter on T2WI. The lobes, sulci, cerebral fissures, cerebral cistern and ventricle have natural morphology without deformation And increase or decrease, the centerline structure is centered.

Clinical significance of craniocerebral MRI

Abnormal results: MRI plain scan of ischemic cerebral infarction manifested as sheet-like or fan-shaped T1. On the left frontal parietal white matter area, a large T1 long T2 finger edema was seen, which was partially invaded to the contralateral side through the corpus callosum. On T2WI, the edge of the round lesion in the edema showed a low signal, and the small wall nodule was seen, T1WI After enhancement, the lesion wall showed a "garland-like" obvious enhancement, and no obvious enhancement was seen in the center. Considering the patient's age, the possibility of advanced glioma was considered to be the greatest. Fluid-containing cysts showed changes in long T1 and long T2 signals, while mucoprotein nuclear lipid cysts showed changes in short T1 and long T2 signals. When brain tissue edema occurs, T1 and T2 are prolonged, showing a low signal, and T2WI is a high signal. Acute hematoma, T1WI and T2WI showed equal or slightly lower signals; subacute semester, T1WI and T2WI hematomas increased around the signal and progressed to the center; chronic hematomas, T1WI and T2WI showed high signals, and iron-containing hemosiderin formation may occur around During the cystic phase, T1WI showed a low signal, T2WI showed a high signal, and the surrounding low signal loop was more obvious.

Various diseases need to be diagnosed in conjunction with specific conditions. People to be checked: elderly people, people with frequent brain pain.

Brain MRI examination precautions

Unsuitable people: (1) Those who have artificial pacemakers and nerve stimulators are not allowed to be examined. (2) Persons with silver clips in the skull and metal foreign bodies in the eyeballs are not allowed to be examined. (3) The ECG monitor cannot enter the MRI examination room. Examination of arterial disease, heart surgery, and artificial heart valves is prohibited. (4) Various critically ill patients: such as coma after trauma or accident, irritability, arrhythmia, respiratory insufficiency, continuous blood loss, and incontinence. (5) Metal objects (such as internally fixed steel pins, etc.) at the inspection site cannot be inspected. (6) Pregnant women should be examined carefully. If you are pregnant, please inform the examining doctor. Contraindications before examination: No special contraindications. Requirement during the examination: Examine and relax, and follow the doctor's instructions to carry out the examination. Please bring the medical records, X-ray films, CT films, previous MRI films and other information with the MRI room for reference.

Brain MRI examination process

Magnetic resonance imaging (MRI) is a new inspection technique based on the principle that magnetic nuclei can generate transitions between energy levels under the action of a magnetic field. MRI is helpful to check the energy state and cerebral blood flow of patients with epilepsy, and it is of great value in the diagnosis of degenerative diseases. MRI is achieved by the external high-frequency magnetic field, which generates signals from auxiliary energy in the body to the surrounding environment. The imaging process is similar to image reconstruction and CT, but MRI does not rely on external auxiliary radiation, absorption and reflection, and does not rely on radioactivity. -assisted emission of matter in the body, but the use of external magnetic fields and objects to image, high-energy magnetic field is not harmful to the human body. So MRI is safe. The patient enters the examination room and explains the scan before the MRI instrument.

Brain MRI examination related diseases

Dementia, watershed cerebral infarction, lacunar cerebral infarction, progressive supranuclear palsy, aponectomy cerebellar atrophy, multiple system atrophy, vascular Parkinson's syndrome, Machado-Joseph disease, pneumococcal meningitis, pediatric primary Brainstem injury