Surgery; its theory and practice . of the muscles fromthe deep into the superficial veins. Some authors consider thislast the chief, if not the only cause of varicose veins of the lowerextremities. They maintain that the pressure of the blood firstproduces a dilatation of the superficial veins where the intermus-cular veins empty into them ; that this dilatation being frequentlyrepeated becomes permanent; that the valves in consequence areunable to close and i)rotect the veins, and being thrown out ofuse gradually undergo atrophy, whilst the weight of the columnof blood, from the inefficiency
Surgery; its theory and practice . of the muscles fromthe deep into the superficial veins. Some authors consider thislast the chief, if not the only cause of varicose veins of the lowerextremities. They maintain that the pressure of the blood firstproduces a dilatation of the superficial veins where the intermus-cular veins empty into them ; that this dilatation being frequentlyrepeated becomes permanent; that the valves in consequence areunable to close and i)rotect the veins, and being thrown out ofuse gradually undergo atrophy, whilst the weight of the columnof blood, from the inefficiency of the valves, becomes further in-creased, and the veins still further dilated. B. Chan^^es in thevein-walls.—These consist principally in an hereditary weakness,want of muscular tone, and inflammatory softening of the veins are more common in men than in women, owing totheir more frecjuent exposure to the exciting causes. Women,however, are peculiarly liable to them during pregnancy. VARICOSE VEINS. 307 Fig. Varicose ? veins. (FromBryants Surgery.) Pathology.—^A varicose vein is lengthened, dilated, and fre-quently tortuous (Fig. 106), the dilatation being especially markedwhere the intermuscular veins open into thesuperficial, and at the situation of the middle, and to a less extent the outercoat, are often greatly thickened by the forma-tion of fibrous tissue, but the inner coat showslittle change. In the dilated portions im-mediately above the valves the coats, on theother hand, may be found greatly thinned, sothat the vein maygive way at these valves themselves, from the dilatation ofthe veins, cease to be of service, and becomeatrophied and frequently reduced to mereridges or fibrous cords. Thus the intravenouspressure in the segment below is increased asthe column of blood in the upper part of thevein is no longer supported by the deep veins are generally involved in thevaricose condition, and the smaller radi
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Keywords: ., bookcentury1800, bookdecade1890, booksubjectsurgery, bookyear1896
