Brain CT scan: What you need to know

The article was professionally consulted by Specialist Doctor I Vo Cong Hien - Radiologist - Radiology Department - Vinmec Nha Trang International General Hospital.

Brain tomography, also known as CT scan of the brain, is an imaging test performed when examining and treating diseases in the head and face. So does a CT scan of the brain have any effect?

A brain scan, also known as a CT scan of the brain, is a method of using X-rays to take pictures of the head and face, the results of which will provide information about the eyes, facial bones, and air-filled spaces in the bones near the nose (sinus) ), inner ear. CT scan of the brain is a method used to evaluate diseases with common symptoms such as headaches.
During the scan, the patient will lie on an x-ray table attached to a CT scan machine. The patient is asked to place the head in the scanner and X-rays are beamed through the head. With a CT scanner, each angle produces a small slice of the head and face. To capture multiple angles, each part of the camera is tilted in different directions.
In some cases, the patient is prescribed contrast injection into the veins of the arm or spine. Contrast makes it easier to make CT scans of the structures and organs that need to be captured on images. In addition, contrast dye is also used to check the circulation of blood and tumors, nerve areas are infected or damaged or not.

CT scan of the brain is indicated to help doctors diagnose or monitor the following conditions:
Birth defects in the head or brain; Have a brain infection, meningitis, encephalitis, brain abscess, tuberculous brain or tuberculous meningitis;

Have a brain tumor; have hydrocephalus (a buildup of fluid in the brain); Early fusion of skull joints; Injury to the head or face: Traumatic brain injury and multiple trauma; CT scan of the brain in cases of stroke or bleeding in the brain; Cerebrovascular accident: It can be a transient cerebrovascular accident or a cerebrovascular accident with focal neurological signs such as facial paralysis, hemiplegia, aphasia...; When there are neurological signs such as: Convulsions, seizures, migraine, dizziness; Suffering from increased intracranial pressure syndrome with symptoms such as nausea, headache, blurred vision. A CT scan of the brain is done to determine the cause of the following symptoms:
Headache, fainting, especially when certain signs and symptoms are present; Vision problems, hearing loss, decreased muscle tone, numbness and tingling, communication difficulties, problems swallowing food; Change in thinking and behavior.

3.1 Advantages of brain tomography The image is clear; The soft tissue image resolution is much higher than that of radiography; Fast imaging time, especially when it is necessary to survey and evaluate emergency patients; High spatial resolution; Is the optimal method for diseases with contraindications to magnetic resonance imaging. 3.2 Disadvantages of brain tomography Due to the limitation of strong penetrating power of X-rays, CT scan is more difficult to detect soft tissue lesions than MRI; Lesions of the same intensity are difficult to detect and distinguish; The image resolution of CT is lower than that of MRI, especially for soft tissue structures, so CT scans are difficult to detect small lesions.

CT scan is a technique that uses X-rays, so it can cause radiation, however, with the level of radiation exposure per scan is minimal and within the allowable limits.
For pediatric patients, the CT scan should be carefully guided before performing. If the child is too young or scared, the doctor may give the child a sedative to help him relax. In addition, the child's family and relatives can also discuss with the doctor about the requirements of a CT scan and the risk of radiation affecting the child.

5.1. Before the CT scan of the brain, the patient removes all metal objects on the body so as not to interfere with the scan (hairpins, metal-rimmed bras, jewelry, glasses, watches, etc.) , hearing aids, dentures); Patients need to notify medical staff if they have one of the following diseases: asthma, venous disease, diabetes, kidney disease, drug allergy; Patients need to inform medical staff if they are pregnant or suspect that they are pregnant; Patients or family members sign a commitment if they need to inject contrast when taking CT scan; Patients need to fast before contrast injection for 4-6 hours if needed and can still drink water (with a moderate amount) 2 hours before the scan; If the person is an infant or toddler, the doctor may recommend sedation to keep the child calm and still at the scan site. 5.2. During a CT scan of the brain The patient lies on his back on the examination table in the examination room, the patient may be asked to lie in some special positions to serve the diagnosis;

The average scan time is from 3 to 5 minutes, in some cases it takes longer (15, 30 or 45 minutes), the medical staff will explain more while taking the picture; The patient needs to lie still during the CT scan; If the patient has contrast injection, there will often be a burning sensation along the arm, or heat in the face when the contrast is injected, so the patient is advised to try to stay still for the best image. 5.3. After the CT scan of the brain If the patient does not inject contrast, he or she can function normally after the scan, can eat and drink if no other tests are done (depending on the type of test); If the patient is injected with contrast, it is necessary to drink a lot of water to increase the excretion of contrast from the body; If after the CT scan, the patient finds any abnormalities such as: dizziness, nausea, vomiting, itching, redness of the skin, fatigue, fever, difficulty breathing, etc., it is necessary to immediately notify the medical staff or go to the hospital. nearest medical facility for examination.

After the scan, the results will be returned within 30 - 60 minutes. Some cases will take longer to return results if consultation is required; Normal CT scan results of the brain are: The size, shape and position of the brain, blood vessels, brain bones and face are normal; no peripheral objects or metastatic growth were present; no brain bleeding or fluid accumulation in the brain; Abnormal CT scan results are: There are metastatic growths of tumors, bleeding in or around the brain; foreign body in the brain; broken, deformed, abnormal brain or facial bones; the nerves leading to or from the brain are damaged; fluid buildup in the brain, bleeding in or around the brain; cerebral aneurysm; swelling, edema, or changes that lead to stroke occur in the area around the brain; The sinus wall is thick, the sinuses are filled with fluid. Brain tomography is a technique widely applied in clinical practice to detect diseases with tumors, cerebral hematomas, cerebral bleeding, cerebral ischemia, cerebral edema,... in neurology. skull.
Vinmec International General Hospital is proud to be one of the hospital systems in the country that has invested in modern CT scanners with a team of doctors who are leading experts who can conduct imaging and diagnosis. , detect cranial pathologies for high diagnostic and treatment efficiency.
BSCK I Vo Cong Hien has many years of experience in the field of imaging, especially in diagnostic ultrasound for general abdominal diseases, advanced cardiac - vascular, obstetrics and gynecology. Doctor Vo Cong Hien used to work at the Imaging Department of the University of Medicine and Pharmacy Hospital - Hoang Anh Gia Lai before working at the Imaging Department of Vinmec Nha Trang International General Hospital.