cerebral artery inner diameter middle cerebral artery inner diameter 2012-10-03T05:48:00Z JSmith MCA inner diameter The length of a line which crosses a transverse view of a middle cerebral artery, passing through its center and ending on either side at the inner surface of the blood vessel wall. The middle cerebral arteries are the largest of the cerebral arteries and supply blood to the lateral cerebral cortex, anterior temporal lobes and insular cortices of the brain. middle cerebral artery lumen diameter