Rare in animals. Angioma Varix. Superficial. Deep. Causes, obstructed
circulation, compression, congestion. Symptoms, enlargement,
elongation, tortuosity of veins, stiffness, lameness, complications.
Treatment, 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 involves 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.
_Causes._ 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 tissue), 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 forgotten. Varix of the saphena is usually an attendant or sequel of
tibio-tarsal synovitis, and is the result of combined pressure and
congestion. Mammary varices are manifestly connected with the congestion
and exudations which affect the udder and environment at the time of
parturition, or with a casual mammitis.
The _symptoms_ in superficial vessels are visible enlargement, and often
elongation and tortuous direction of the vein or veins, with or without
tenderness. Deep-seated varicosities may be attended by stiffness of the
part and a halting in progression with or without pain on pressure.
These cases may recover spontaneously as the result of adhesive
phlebitis, or they may develop phlebolites, suppuration, inflammation,
ulceration and hæmorrhage.
_Treatment._ Superficial varices have been treated by compression,
cauterization, coagulating injections, and ligature. It is not often
that interference is demanded but in such cases, pressure with elastic
bandage having failed, ligature with antiseptic precautions is
indicated.