VARICOSE VEINS. DILATED VEINS WITH 

 ALTERED WALLS. 



Rare in animals. Angioma Varix. Superficial. Deep. Causes, ob- 

 structed circulation, compression, congestion. Symptoms, enlargement, 

 elongation, tortuosity of veins, stiffness, lameness, complications. Treat- 

 ment, compression, coagulants, cauterization, ligature. 



Varix is not so common in the lower animals as in man, and is 

 generally observed in the superficial veins, so that it comes under 

 the domain of surgery. In the form of angioma, which affects 

 the veins, there is extensive dilatation and elongation, but it in- 

 volves a large group of connecting and anastomosing veins, 

 whereas varix usually affects but one or a few connecting vessels. 

 In the horse the most common seat of varix is in the saphena 

 vein, as it passes obliquely over the inner side of the hock. Less 

 frequently it appears on the flank or other superficial part. In 

 cattle the mammary veins are the most frequent seat. Varices, 

 however, occur also in deep-seated veins and in connection with 

 normal venous plexuses, as in the buccal, palatal, and peneal. 

 Anatomically they may be simple fusiform dilatations, as in the 

 saphena ; dilated, elongated and tortuous, branching trunks, as 

 in the mammary veins ; or dilated veins with thickened walls and 

 pouch like dilatations. 



Caiises. There is usually some obstruction to the circulation 

 through the affected vessel, it may be by pressure by a tumor, or 

 a constrained position, obliteration by a phlebitis and thrombus, 

 extension of inflammation from adjacent organs, increased blood 

 pressure by gravitation, or from diseased heart or lungs. 

 Whether from the extension of contiguous inflammation, from 

 external pressure, or from blood tension, the morbid process has 

 much in common ; the circulation and nutrition in the vascular 

 walls are interfered with, degenerations set in (softening, fatty, 

 connective ti.ssue), which predispose to dilatation under the blood 

 pressure. The pouch-like dilatations of the jugular consequent 

 on bleeding, are essentially traumatic. The impaired innervation 

 which lessens the resistance of the vascular walls is not to be for- 

 gotten. Varix of the saphena is usually an attendant or sequel 



363 



