Quantitative Analysis Of Capillaries In Optic Nerve Head Of Primary Open-angle Glaucoma

Purpose: Primary open-angle glaucoma (POAG) is a common ophthalmopathy leading to blindness. The present study is to observe the structure and quantity of capillaries in ONH of POAG.Methods: The vasculature of ONH in clinicopathological slides (1um) from 3 cases of POAG, 2 cases of normal human eyes had been examined. The structural character in each region of ONH could be assessed under light microscopy. The width-to-length ratio,volume density (Vv),quantity density (NA) and relative area ratio (Ss) of capillaries in ONH had been measured by computer image analysis and stereological methods. It could be quantitatively compared in number,density,caliber and volume of capillaries between control and POAG group.Results:1,In control group, the optic nerve fiber bundles exhibited radiative structure which center was located the central retinal artery (CRA) in lamina cribrosa. The partition of laminar beams was clear. The structure of lamina cribrosa in POAG group was derangement, and was very hard to distingush the difference in prelaminar region,lamina cribrosa region and postlaminar region.2,In control group, the distribution of capillaries of laminar beams in ONH was normal. There was no significantly different of width-to-length ratio of capillaries between control and POAG group.(P>0.05).3,Compared the POAG group with control one, the Vv and Ss ofcapillaries in ONH were significantly reduced (P<0.05), The morphometer NA in POAG group was no different with control (P>0.05).Conlusion: The vascular volume of ONH was decreased in POAG. It maybe caused by vasoconstriction rather than the reduction of capillary numbers...