The imaging technique called provides information about what part of the brain does blood go by injecting a radioactive dye

There are two tests that are used for this. The less invasive test would be CT Scan with contrast. The minimum invasive approach isca test called Cerebral angiography where an iodine contast is injected intravenously and an imaging catheter is inserted through the groin all the way up to the brain to see how blood is circulating

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