Ross R T, Morrow I M
Can J Neurol Sci. 1984 May;11(2):262-8. doi: 10.1017/s0317167100045510.
Stenosis of the internal carotid artery reduces the flow velocity in the ophthalmic artery. Lowered velocity permits increased red cell aggregation and decreased red cell deformability which increases viscosity. Contrary to the theory of remotely originating emboli, this is an alternate hypothesis regarding transient attacks of ocular and cerebral ischemia. The ophthalmic artery circulation time was measured in two groups of patients. The circulation time was defined as the interval between the appearance of contrast media in the siphon of the internal carotid artery and in the ocular choroid. The measurement was made on 151 angiograms of 108 subjects. These vessels were normal. An additional 76 patients had 108 angiograms which showed various amounts of internal carotid artery stenosis. These 76 patients had transient ischemic attacks; retinal, cerebral, or both. There is a significant difference in the ophthalmic artery circulation time in the two groups. The slowing in the ophthalmic artery is related to the degree of internal carotid artery narrowing. The circulation time in a cerebral branch of the internal carotid was not measured. It is presumed that stenosis of the internal carotid artery would have the same effect on a cerebral artery as on the ophthalmic artery.
颈内动脉狭窄会降低眼动脉的血流速度。血流速度降低会使红细胞聚集增加，红细胞变形性降低，从而增加血液黏稠度。与远端栓子起源的理论相反，这是关于眼部和脑部缺血性短暂发作的另一种假说。对两组患者测量了眼动脉循环时间。循环时间定义为造影剂出现在颈内动脉虹吸部和眼脉络膜之间的间隔时间。对108名受试者的151张血管造影片进行了测量。这些血管正常。另外76名患者有108张血管造影片，显示出不同程度的颈内动脉狭窄。这76名患者有短暂性脑缺血发作；累及视网膜、脑部或两者。两组患者的眼动脉循环时间存在显著差异。眼动脉血流减慢与颈内动脉狭窄程度有关。未测量颈内动脉脑部分支的循环时间。据推测，颈内动脉狭窄对脑动脉的影响与对眼动脉的影响相同。
