brain metabolic imaging

Brain metabolic imaging can accurately understand the neuronal activity and metabolic changes under normal conditions and disease states, as well as the metabolism of cerebral cortex under different physiological conditions and mental activity. Through PET, we can intuitively understand the metabolic activity of human brain and various physiological or pathological metabolic changes, and reflect them in an image. Keep your position still, it is best to lift your hands during the whole body examination, check about 15~20min; do not need to lift your hands for brain examination, check about 5~10min. Basic Information Specialist Category: Inspection Category: CT Applicable gender: whether men and women apply fasting: fasting Tips: Check the fasting, ban on alcohol, banned drinking sugary drinks, and ban intravenous drip of glucose at 9:00 on the night before the check. Drink a small amount of water. Remove the metal ornaments (such as belts, keys, jewelry, coins, etc.) worn on the body before imaging; drain the urine before the imaging (be careful not to stain the clothes or skin with urine to avoid misdiagnosis). Normal value 1. The brain metabolic images of normal people are similar to those of cerebral blood perfusion images. The cerebral cortex, basal ganglia, thalamus, and cerebellum are highly radioactive, and the sides are basically symmetrical. 2. The reference value of CMRGlu is 20 (51 (mol/(100 g.min). The LCMRglu in each brain region has corresponding reference values. The average LCMRglu of the left and right cerebral hemispheres is 37.67 (8.67 (mol/(100 g. Min) and 37.11 (8.72 (mol/(100 g.min). As the age increases, the LCMRglu value decreases. 3. The reference value of gray matter CMRO2 is 259 (mol/(100 g.min), and the white matter is 80 (mol/(100 g.min); the OEF reference values ​​of gray matter and white matter are 0.49 and 0.48, respectively. Clinical significance Abnormal results can be diagnosed and studied according to the results of image acquisition and data processing. 1. Location diagnosis of epileptic foci; 2. Early diagnosis and differential diagnosis of dementia; 3. Diagnosis and classification of benign and malignant brain tumors, evaluation of curative effect, recurrence or detection of residual tumors; 4. Early diagnosis of Parkinson's disease; 5. Research on brain physiology and cognitive function; 6. Research on mental disorders. People with neuropsychiatric diseases such as schizophrenia, depression, dementia, epilepsy, and Parkinson's disease who need to be examined. Precautions Taboo before inspection: 1. Drinking water: 30 minutes after the injection of 18F-FDG, drinking 3-4 cups, about every 10 minutes; 2. Remove the metal ornaments (such as belts, keys, necklaces, jewelry, coins, etc.) worn by the body before imaging; 3, before the imaging is exhausted in the urine (be careful not to contaminate the clothes or skin, so as not to misdiagnose); 4. The examinee started fasting, banned alcohol, banned drinking sugary drinks, banned intravenous drip of glucose, and banned from vigorous or prolonged exercise at 9:00 pm on the day before the examination. Drink a small amount of water; 5, check the day to avoid talking with people, do not chew gum, etc.; avoid stressful position; 6. When you come to the PET/CT center, please bring along the relevant information (medical records, treatment records, pathological results, imaging examination data such as CT, X-ray, MRI, DSA, B-ultrasound, bone imaging, etc.). Requirements for inspection: 1. Keep quiet before and after injection of imaging drugs, and rest in a lying position or a semi-recumbent position, try to avoid walking; 2, need to calmly breathe during the examination, it is not appropriate to take a deep breath; some subjects need to hold their breath for a few seconds (according to the doctor's advice); 3, keep the position does not move, the best hands to lift the whole body examination, check about 15 ~ 20min; brain examination does not require hands to lift, check about 5 ~ 10min. Inspection process 1. Brain glucose metabolism imaging: Glucose is almost the only energy substance in brain tissue. 18F-FDG is a glucose analog with the same cellular transport and glycosylation phosphorylation process as glucose, but it is no longer involved in the further metabolism of glucose and is retained in brain cells after conversion to 18F-FDG-6-P. The subjects were fasted for more than 4 hours, and PET or SPECT/PET brain glucose metabolism imaging was performed 45-60 min after intravenous injection of 18F-FDG 185-370 MBq. The regional brain glucose metabolic rate (LCMRglu) and whole brain glucose metabolic rate (CMRglu) were calculated in various parts of the brain. 2. Brain oxygen metabolism imaging: The weight of normal human brain only accounts for 2% of the body weight, but its oxygen consumption accounts for 20% of the whole body. Therefore, brain oxygen consumption is an important reference index reflecting the functional metabolism of human brain. The patient's dynamic imaging of PET immediately after inhalation of 15O2 can obtain the cerebral oxygen metabolism rate (CMRO2), and the oxygen uptake score (OEF) can be calculated in combination with the CBF measurement. 3. Brain protein metabolism imaging: using 11C-MET (11C-methyl-L-methionine), 11C-TYR (11C-tyrosine), 18F-FET (18F-fluoroethyl tyrosine) and 123I -IMT (123I-iodomethyltyrosine) or the like as an imaging agent can obtain an image reflecting the function of amino acid uptake and protein synthesis in the brain. Not suitable for the crowd Inappropriate people: pregnant women, emotional instability or persistent sputum are banned.