Blockages to the proximal ( A1 ) segment of the vessel produce only minor deficits due to the collateral blood flow from the opposite hemisphere via the anterior communicating artery.
12.
The thalamus derives its blood supply from a number of arteries : the polar artery ( posterior communicating artery ), paramedian thalamic-subthalamic arteries, inferolateral ( thalamogeniculate ) arteries, and posterior ( medial and lateral ) choroidal arteries.
13.
The anterior optic nerve is supplied by the short posterior ciliary artery and choroidal circulation, while the retrobulbar optic nerve is supplied intraorbitally by a pial plexus, which arises from the ophthalmic artery, internal carotid artery, anterior cerebral artery, and anterior communicating arteries.
14.
Luria's other books written or co-authored during the 1960s included : " Higher Brain and Mental Processes " ( 1963 ), " The Neuropsychological Analysis of Problem Solving " ( 1966, with L . S . Tzvetkova; English translation in 1990 ), " Psychophysiology of the Frontal Lobes " ( first published in 1973 ), and " Memory Disorders in Patients with Aneurysms of the Anterior Communicating Artery " ( co-authored with A . N . Konovalov and A . N . Podgoynaya ).
15.
These approaches are based on general experience, and the only randomized controlled trial directly comparing the different modalities was performed in relatively well patients with small ( less than 10 mm ) aneurysms of the anterior cerebral artery and anterior communicating artery ( together the " anterior circulation " ), who constitute about 20 percent of all patients with aneurysmal SAH . This trial, the " International Subarachnoid Aneurysm Trial " ( ISAT ), showed that in this group the likelihood of death or being dependent on others for activities of daily living was reduced ( 7.4 percent absolute risk reduction, 23.5 percent relative risk reduction ) if endovascular coiling was used as opposed to surgery.
