Cerebral blood flow imaging

Cerebral blood flow imaging includes cerebral blood perfusion tomography, 133Xe cerebral blood flow measurement, and imaging and stress test cerebral perfusion imaging. This test is used for the diagnosis of cerebral ischemia, cerebral infarction, diagnosis and differential diagnosis of Alzheimer's disease, and localization diagnosis of epileptogenic focus. Stop taking sedatives, stimulants, and other drugs that act on the nervous system 24 hours before the test to avoid illusions during the test and affect the judgment of the test results. Basic Information Specialist Category: Inspection Category: CT Applicable gender: whether men and women apply fasting: not fasting Tips: Stop taking sedatives, stimulants and other drugs that act on the nervous system 24 hours before the test to avoid the formation of illusions during the examination and affect the judgment of the test results. Normal value The cerebral cortex, basal ganglia, thalamus and cerebellum on both sides of the normal image have high radioactivity, clear images, uniform radioactivity distribution, and basically symmetric distribution. Images of the three transverse planes of the transverse, coronal, and sagittal planes showed no lesions. Clinical significance Abnormal results: 1, cerebrovascular disease: 1 Infarction area of ​​cerebral infarction is radioactive defect or reduced, and can display images of neurological dysfunction in the brain, such as cross cerebellar insufficiency; 2 radioactive reduction of ischemic site in transient ischemic attack; 3 cerebral hemorrhage: radioactive reduction or defect in the local hematoma. 2. Epilepsy has increased radioactivity during the attack period, while radioactivity is reduced during the intermittent period, so epilepsy lesions can be located. 3, dementia identification: Alzheimer's disease showed bilateral apical and temporal lobe-based cerebral cortex symmetry is significantly reduced, and does not involve the basal ganglia and cerebellum. The people who need to be examined have cerebral ischemic diseases, cerebral infarction, Alzheimer's disease, and epilepsy. Precautions Pre-examination contraindications: Stop taking sedatives, stimulants and other drugs that act on the nervous system 24 hours before the test to avoid the formation of illusions during the examination and affect the judgment of the test results. Oral potassium chlorate 400mg was taken 30 minutes before the examination to close the choroid plexus; 10 minutes before the injection of the imaging agent, black eye mask and earplugs should be worn until 10 minutes after injection to remove, and the eyes were closed and quietly rested before imaging. Requirements for inspection: The examination must be carried out within 3 hours after the meal. If you cannot eat before the examination, you should follow the doctor's instructions, orally take 50 grams of powdered sugar or 40 ml of 50% glucose intravenously to prevent hypoglycemia. The result of the inspection. The head cannot be moved during the inspection to ensure the authenticity of the image. Inspection process 1, cerebral blood flow perfusion imaging. Before the cerebral blood perfusion imaging, the patient took oral potassium perchlorate 400mg to block the uptake of pertechnetate (99mTcO4) by the choroid plexus. After 30 minutes, the cerebral blood flow perfusion imaging agent 99m锝 double was injected through the elbow vein. Cysteine ​​ethyl ester (99mTc-ECD) 740925mBq. The collection was started 30 minutes after the injection. The patient lies on the fault bed and brakes his head. Acquisition matrix 128×128, magnification 1.0, step acquisition, 1 frame per rotation, 6 frames, a total of 60 frames, 2530s per frame. The original data was processed by a computer workstation (X-Pert) and the reconstruction was performed with Henning filtering with an attenuation correction factor of 0.11. Cross-sectional, coronal, and sagittal tomographic images parallel to the line connecting the external and external ear holes were obtained. 2. Acetazolamide load test. After 48 hours of brain SPECT examination, 2 g of acetazolamide (produced by Jiangsu Chennai Pharmaceutical Co., Ltd.) was taken orally, and SPECT examination was performed 2 hours later. The other steps are the same as above. 3, 133Xe cerebral blood flow measurement and imaging. The subject was placed on his back, and the head was placed in a helmet of a multi-probe detecting device, and a 133Xe 133Xe-O2 mixed gas of 185 MBe/L was inhaled for 1 min, followed by inhalation of air for 15 min. The multi-probe system was started to record for 10~15min, and the rCBF and the gray matter flow distribution map of the corresponding parts of each probe were obtained by computer processing. If tomographic imaging must be completed in a short time using a high-speed rotation and high-sensitivity SPECT system. 4. SPECT image analysis. Qualitative analysis was performed by two doctors using visual methods, and abnormalities in the radioactivity that were visible to the naked eye on two or more mutually perpendicular levels were considered lesions. The X-Pert workstation computer-specific software was used for quantitative analysis. The cerebellar regional cerebral blood flow (rCBF) was 100%, and the rCBF and right/left (R/L) ratios of each brain region were calculated. Not suitable for the crowd Inappropriate population: Patients who are allergic to potassium perchlorate and imaging agents.