Study Of The Development Of Human Cerebral Artery Relative To Aneurysm

Department of Neurosurgery,Zhujiang Hospital, The First Military Medical University,Guangzhou ABSTRACT Objective The cause of intracranial saccular aneurysms has been disputed for a long time,but it is unknow today.One of the focuses has been debated is concered with the wall's change at the bifurcation of cerebral arteries.The present investigation was carried out to study whether medial defect exist and the structural characteristic and histogenesis of elastic fibers and medial smooth muscle cells(SMCs) at the bifurcations in human intracranial arteries.we aslo want to do some help to comprehend and assess the hypothesis for the occurrenc of saccular aneurysms,at the same time. Method We collect the foetuses which haven't appearance malformation of different gestational age.lt will- be fixed by 10% formaldehyde in 1.5h after induced labor and be filled by 10% gelatin and a small quantity of prepared Chinese ink after fixed. Segments of the arteries from the circle of Willis of the foetuses,including bifurcations.are sectioned in 1 of 3 orthogonal planes and been stained by hematoxylin and eosin (HE) for SMCs or aldehyde-fuchsin for elastic fibers.The thickness of slices are 6.0 V- m.We observe the 3-dimensional structure with light microscope.ResuIt The number of the layers of elastic fibers and medial SMCs of the intracranial arteries from the circle of Willis are 1.5-12.6 and 1.1-9.0 respectively.And 70.6% of the foetuses and 30.3% of the specimen are disclosed the local defects of the medial SMCs at the bifurcations of the developing arteries. We find the structure of elastic fibers disorganized in 4 segments and the number of the layers of elastic fibers decreasing in 3 segments.Conclusion The lawof the human cerebral arteries angiogenesis has been found.And the number of the layers of elastic fibers and medial SMCs develop with the foetuses.The congenital anomaly of the elastic fibers and SMCs are proved by this experimentjSupporting a possible pathogenesis for intracranial saccular aneurysms.