Healing of Wounds in Veins. — The condi tion of the wound and its mode of healing de pend upon the character and direction of the wound. If the wound be linear, and made in the axis of the vessel or somewhat ob. liquely, and there be not, much bleeding, its lips will come together, adhere, and rapidly form a linear cicatrix. If, however, it be transverse, or if much bleeding occur from it, a coagulum will form in and over the aperture. "An oval naked coagulum forms the plug of the orifice, and a flattened co vered clot, which is an extravasation into the cellular sheath, extends to some distance around it."* In twenty-four hours the lips of the wound are found separated, the edges are everted and adhere to the clot. At the expiration of three days the internal margin of the wound is elevated and rounded, and a thin, narrow, membranous expansion, parti ally extending over the inner surface of the clot, is seen to be continuous with the everted edge of the internal tunic. The clot is more compact and lamellated. At the fifth day the membranous appearance extends over the whole inner surface of the clot. Subsequently the clot becomes more and more absorbed, and the new membrane, extending from the lips of the wound, becomes more organ ised. Vasa vasorum can be seen on it by means of a lens from the twelfth to the six teenth day. " On the twentieth day it is only possible to distinguish the recent from former wounds, by the tenuity, smoothness, and transparency of the new membrane compared with the old, which is dense, tough, and wrinkled." These dates, &c. refer to the wounds made in ordinary bleeding operations; in larger wounds the process is proportion.. ately longer. The wound is ever after indi cated by the peculiar thin, transparent, exten sile membrane with which it was repaired. If a vein, having one of these cicatrices in it, be injected with water, the new membrane bulges out, on account of its elasticity, into a pouch or bag.t Mr. Travers is quite con vinced that this new membrane is continuous with the internal membrane of the vein.
Ejects of Ligatures on Veins. — The effects of ligatures on veins are different from those on arteries. The coats of the vein are, by the ligature, thrown into longitudinal folds, which are indicated when the vessel is slit up, and its interior examined. The effect on the ele mentary coats of the veins is different from that produced by ligature on the arteries : instead of the deep cut through the inner and middle coat, which occurs in the latter, there is hut a slight indentation, correspond ing to the ligature on the vein. This is produced by the lesion of the thin internal tunic, and that alone. As regards the rest of the thickness of the vein's walls, it ap pears that the outer or cellular tunic is di vided, leaving the middle condensed portion of the venous wall uninjured. Upon a close examination, however, it is found that one element --namely, the yellow elastic tissue is divided throughout the entire thick ness of the outer and middle coats, leaving the continuity of tube to be maintained by the white fibrous element, which does not stiffer division ; and therefore that part of the wall where the white fibrous clement is most condensed and abundant is that where least impression is made by the ligature. A thin,
tightly tied, string produces the deepest im pression.
According to Mr Travers, when a ligature has been applied for a period of from twenty-four hours to five days, it has produced the follow. ing changes :— " The vein above and below is thrown into longitudinal folds on either side of the ligature. The portion next the heart is perfectly empty and collapsed ; that next the extremity is filled to distension by a long, and, generally, firm, coagulum of blood, which is a mould pf the vessel, and bears the impression of its semilunar valves. The coagulum tends for several inches; it is not always com pact and lamellated, and adhering to the in ternal tunic, being sometimes less consistent and broken ; but it always fills the calibre of the vein. There is no blush upon the in ternal tunic, much less any sign of adhesive inflammation, or thickening of the proper coats of the vein, or agglutination of its contiguous folds ; these folds being effaced on the re moval of the ligature ; but the cellular sheath is thickened by a deposit of lymph in the vi cinity of the ligature." * If two ligatures be applied, and the vessel divided between them, the ends retract about an inch. At the se venth day the interstitial deposit of lymph among the areolar tissue around the vein is very dense, and forms a hard fibrinous mass, through which the ligature runs in a sort of canal. According to Mr. Travers, ulceration commences on the ninth day, and lasts from fifteen to twenty-five days. " The ulcerated ends of the vein formed a crescentic sweep, and were separated to the extent of an inch, and fastened by adhesion to the cellular sheath, which was much extended and thickened by a subjacent deposition of lymph, so as to form a smooth solid bed between the divided ends of the vein. The internal membrane of the superior portion of the vein had a thin ragged edge, where it had been severed by ulceration. The lower edge was smooth and blended in with the bed of the wound. The extremities had undergone no contraction but that produced by the adhesion of the severed extremity to the sheath. The portion of the vein next the heart was empty. The upped was filled by a dark lamellated coagulum of blood, adhering very strictly to the internal tunic, which was discoloured by it. On care fully separating the outer lamella; which coated the interior of the vein, I could not discover any thickening of the proper coats of the vein, nor any appearance of inflammatory action within its canal, nor was any such ap pearance indicated in the lower portion of the vein4 Phlebectesis — Varix. — Dilatation of veins is not only the commonest morbid change in veins, but is the most frequent single patho logical condition that occurs in the human body.