Any vein in the body may become varicose, but the condition is rare
except in the veins of the lower extremity, in the veins of the
spermatic cord (varicocele), and in the veins of the anal canal
(haemorrhoids).
We are here concerned with varix as it occurs in the veins of the lower
extremity.
_Etiology._--Considerable difference of opinion exists as to the
essential cause of varix. The weight of evidence is in favour of the
view that, when dilatation is the predominant element, it results from a
congenital deficiency in the number, size, and strength of the valves of
the affected veins, and in an inherent weakness in the vessel walls.
The _angioma racemosum venosum_ is probably also due to a congenital
alteration in the structure of the vessels, and is allied to tumours of
blood vessels. The view that varix is congenital in origin, as was first
suggested by Virchow, is supported by the fact that in a large
proportion of cases the condition is hereditary; not only may several
members of the same family in succeeding generations suffer from varix,
but it is often found that the same vein, or segment of a vein, is
involved in all of them. The frequent occurrence of varix in youth is
also an indication of its congenital origin.
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