Yes, I'm sure the EC-IC and the STA-MCA is the same thing. Through much technical research on moyamoya, we are not talking about different arteries here, just different
branches of the common carotid artery (internal/external). It's why the re-routing of blood around the blockage works!
Here's a quote from the Penn State Neurosurgery site:
"During microsurgical
EC-IC bypass, dissecting the
superficial temporal artery (STA) from the scalp, and ‘plugging it in’ to a brain vessel, usually a branch of the
middle cerebral artery (MCA) thus increasing the blood supply to the brain."
Here's a picture from Loyola University in Chicago that may help show what the arteries look like:
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As for the carbon dioxide reactivity test, it sounds pretty much like the SPECT scan which shows blood flow (oxygen content) to the brain, kinda like this:
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Love, DJ