1402 



VEIN. 



cancerous uterus, from an ulcerated leg, &c. 

 Examples of all these are on record. 



What, then, determines their development ? 

 This question it is not easy to answer ; all we 

 can say is, that those circumstances which fa- 

 cilitate mechanically the coagulation of the 

 blood, favour their production; and it is not 

 improbable also that a vitiated state of blood 

 may predispose to and favour their develop- 

 ment : it is certainly probable that the pre- 

 disposing causes, whatever they are, may 

 be started into activity and be made efficient 

 for the production of these bodies, by some 

 temporary local disturbance of the circulation, 

 or by some slight subinflammatory condition, 

 which varicose veins readily take on, and 

 which, were it not for the existence of pre- 

 disposing circumstances, would soon be re- 

 solved. 



Calcareous Degeneration of Veins. The 

 transformation of the walls of veins into 

 earthy tubes, or calcareous deposition among 

 their tissues, is infinitely less common than in 

 arteries. It still however does occur, and 

 apparently in the same manner, by the same 

 progressive changes, and from the existence of 

 the same constitutional tendency, only in cir- 

 cumstances of greater intensity. 



Occasionally patches of atheromatous de- 

 posit consisting, as in arteries, of choles- 

 terine, oil, and phosphate of lime, are seen 

 on the inner surface of veins, though they are 

 always much smaller, and less general than 

 those which are found in the arteries of the 

 same individual. They present a white opaque 

 appearance, and produce a slight elevation of 

 the surface where they are situate. This de- 

 posit becomes converted by degrees into bony 

 matter, as in arteries ; but instances where 

 this has existed to any considerable extent, 

 are very rare. 



There are, however, some few on record. 

 Bailie has described ossification of the inferior 

 cava. Morgagni refers to a case observed by 

 Bonazolius and Stancarius, in which the cava 

 and emulgents were much dilated, and con- 

 verted partly into cartilage and partly into 

 bone. Beclard mentions an instance where 

 the femoral vein was calcined, and it was 

 ])ing in contact with a still more ossified fe- 

 moral artery. Horn noticed ossification of the 

 femoral and uterine veins. Mr. Hodgson re- 

 lates an instance of ossification of the saphena, 

 in which one calcareous patch measured an 

 inch in length ; and Phcebus states that he 

 saw in an anatomical museum an ossified sa- 

 phenous vein taken from a patient fifty-six 

 years of age, who died of cancer of the 

 stomach. By the calcareous deposit the vein 

 was rendered thick and inflexible ; but at the 

 points corresponding with the joints of the leg 

 the vein could be bent. The deposition was 

 between the coats of the vein, and was less 

 regular than that which is found in the coats 

 of arteries. The lining membrane was thick, 

 opaque, and nowhere broken. Microscopi- 

 cally, the deposit presented irregular projec- 

 tions and excavations. Fnrst and Bonctus 

 have found the coronnry veins of the heart 



converted into bone. Otto enumerates in- 

 stances of this change as also having occurred 

 in the splenic, portal, brachial, femoral, and 

 coronary veins. 



A concretion of phosphate of lime, the size 

 of a nut, was found by Andral in the parietes 

 of the external saphena. This might have 

 been an attached phleholite. 



Fatty Tumours. Fatty tumours are occa- 

 sionally developed in the walls of veins around 

 the areolar tissue. Andral mentions one, 

 " I once saw a case of this description, in 

 which a tumour, presenting all the anatomical 

 characters of adipose tissue, was developed 

 between the coats of the vena portss, near its 

 entrance into the liver. This tumour, which 

 was about the size of a walnut, projected into 

 the interior of the vein, and almost entirely 

 obliterated its cavity.* 



Entozoa in Veins. There is upon record 

 a unique example of acephalocysts being deve- 

 loped in the pulmonary veins of the human 

 subject, in which pouches were formed for their 

 reception. The observation was made by 

 Andral. I quote his description in extcnso 

 from the " Clinique Medicale." 



" Several of these (acephalocysts) were 

 lodged in pouches with a smooth surface, 

 which at first seemed to be so many cysts. 

 Others of them empty, and rolled several 

 times on themselves, were contained in nar- 

 row canals, the elongated form of which they 

 assumed. The inner surface of these canals 

 was smooth, like that of the great pouches ; 

 they ramified like vessels. We soon ascer- 

 tained that at each pouch a vessel terminated 

 of small calibre, which, to form it, underwent 

 greater or less dilatation. We then dissected 

 the pulmonary veins, at their entrance into 

 the heart, and we traced them into the lungs: 

 when we had come to the'r almost capillary 

 divisions, we began to perceive several of them 

 present a considerable number of enlargements, 

 which were filled with hydatids. After being 

 thus dilated, the vein resumed its original ca- 

 libre ; then, a little further on, it was again 

 dilated. The largest of the pouches might have 

 contained a large nut, and the smallest would 

 admit a pea. They existed equally in both 

 lungs. The hydatids, which they contained, 

 had all the characters of acephalocysts ; se- 

 veral presented small points of a dull white 

 colour in their substance ; others presented 

 on their inner surface a great number of 

 miliary granulations. Most of them were 

 biirst."f 



Another entozoon, the Distoma hepaticum, 

 has been found in the (hepatic) veins. Several 

 examples have been recorded, but have again 

 been questioned. The matter has, however, 

 now been set at rest. In 1830, M. Duval, at 

 Kennes, demonstrated to an anatomical class 

 several of these parasites in the hepatic veins 

 of a man. They were floating about in the 

 fluid blood. The vessels themselves were free 

 from any lesion. J 



* Andral. foe. cit. 



f Andral, Clinique Me'dieale, p. 555. 



j Duval, Gazette Medicale a Paris, 1842. 



