radionuclide cerebrovascular imaging

Radionuclide cerebral angiography "shot" intravenous injection does not pass the blood-brain barrier imaging agent after rapid dynamic imaging, the imaging process of the imaging process in the cerebral vascular filling, perfusion and clearance can be observed, and The imaging of the internal carotid artery, the anterior, middle and posterior cerebral arteries and the morphological structure can be seen. "Pellet" intravenous injection of 99TcmO4- or 99Tcm-DTPA55 ~ 925MBq (15 ~ 25mCi), dynamic acquisition of 30 ~ 60s in the anterior position at 1 ~ 2s / frame; using computer ROI technology, can get carotid artery and brain time Activity curve, and calculate semi-quantitative indicators such as bleeding perfusion and clearance rate. Basic Information Specialist Category: Cardiovascular Examination Category: CT Applicable gender: whether men and women apply fasting: not fasting Tips: Inappropriate people: Those with a history of severe allergies may consider switching to other methods. For patients suspected of severe pulmonary vascular bed damage and severe pulmonary hypertension, other methods should be considered for examination. Those with severely impaired kidney function and severe edema. Normal value Normally seen: (1) Cerebrovascular dynamic images: 1. The bilateral internal carotid artery, anterior cerebral artery and middle artery of the arterial phase, and the Willis ring of the skull base are successively imaged, showing a bilaterally symmetrical five-fork image, which lasts about 4 s. 2. The brain parenchymal phase Imagingagent enters the microvessels, and the radioactivity is diffusely distributed in the brain parenchyma, which lasts about 2 s. 3. Venous sinus and other sinus sinus development, brain parenchyma radioactivity gradually reduced, lasting about 7s. (2) The cerebral hemispheres on both sides of the brain static image showed a radioactive blank area, and the outer circumference of the skull, the skull base and each sinus showed obvious radioactive concentration areas. Clinical significance Abnormal results: 1. Diagnosis of brain death: Radionuclide cerebral angiography shows delayed development of common carotid artery. Some imaging agents are distributed to the cranial ridge through the branch of the external carotid artery, which has a small amount of radioactive distribution around the brain, but the internal carotid artery and anterior cerebral artery And the middle artery is never developed. 2. Diagnosis of arteriovenous malformation: Radionuclide cerebral vascular imaging showed obvious abnormal radioactive concentration in the deformed part of the arterial phase, and the concentration of the condensate was quickly resolved, and the sinus was developed early. 3. Diagnosis of carotid stenosis and obstruction: The image shows that the carotid artery image is thinned or even interrupted, and the brain parenchyma of the corresponding blood supply area is delayed and the image is lightened. After the arterial phase of the moyamoya disease is normalized in the bilateral internal carotid arteries, the radioactivity is retained in the base of the brain and gradually spreads. The anterior and middle cerebral arteries are obviously delayed in development, and the cerebral blood flow perfusion in the affected area is reduced. 4. Diagnosis of ischemic cerebrovascular disease: vascular perfusion is reduced or deficient in dynamic imaging, and there is obvious abnormal radioactive concentration in the infarct area 2 to 4 weeks after cerebral infarction, the range is consistent with the supply range of the affected blood vessels. After 8 weeks, it turned negative. 5. Diagnosis of brain occupying lesions: cerebral aneurysms and meningioma showed limited concentration in the dynamic image, and did not disappear for a long time. The latter showed a significant abnormal radioactive concentration. The static image of brain abscess showed a "circle"-like radioactive concentration, and the subdural hematoma showed a sharp-shaped crescent-like radioactive thickening on the outer edge of the affected side. Patients in need of examination for brain death, arteriovenous malformation, carotid stenosis and obstruction, ischemic cerebrovascular disease, and brain occupying lesions. Precautions Taboo before inspection: 1. For radionuclide cerebrovascular imaging examination, radionuclide-labeled drugs must be injected. Before the patient is examined, the first-time physician should be consulted in detail and signed to confirm the radionuclide cerebrovascular imaging examination. 2. Remove metal objects from the body before imaging to prevent artifacts. 3, the recent use of tincture, patients must discharge the tincture and then make an appointment to check. Requirements for inspection: 1. Let the body relax and lie flat during the development process, and do not move the body. 2. Lumbar puncture and cerebellar medullary puncture should be performed by a neurologist. Inspection process "Pellet" intravenous injection of 99TcmO4- or 99Tcm-DTPA55 ~ 925MBq (15 ~ 25mCi), dynamic acquisition of 30 ~ 60s in the anterior position at 1 ~ 2s / frame; using computer ROI technology, can get carotid artery and brain time Activity curve, and calculate semi-quantitative indicators such as bleeding perfusion and clearance rate. At 30 minutes after injection, static imaging of the anterior, left, right, and posterior brains was performed. Not suitable for the crowd Inappropriate crowd: 1, those with a history of severe allergies, may consider switching to other methods of inspection. 2. For patients suspected of severe pulmonary vascular bed damage and severe pulmonary hypertension, other methods should be considered for examination. 3, severely impaired kidney function, severe edema.