Varix is a condition of vein which occurs in every possible variety of degree, and in va rious localities, and is generally developed by the superaddition of some mechanical exciting cause upon a constitutional predisposition, by the operation of some local physical in fluence upon veins, which, in common with the other veins of the body, already possessed an abnormal laxity or softness of texture that favours their dilatation.
The structure of veins, already described, pre-eminently favours their dilatation :a structure consisting almost solely of longitu dinal fibres, with comparatively few in a cir cular direction to brace up its calibre, pre sents little to restrain its dilatation beyond the lateral adhesion of the contiguous fibrous rods and their matting together by a certain amount of lateral branching. The coats of veins moreover are very thin, and the amount of distending force applied to them often very considerable.
The anatomical relations of certain veins give them, when in a state of varix, consider. able peculiarities, and various distinctive ap pellations have been conferred upon such local affections, varicacele, hcemorrhoids, &c.: their pathological identity is, however, indisputable.
Though varicosity of the veins is, for the most part, confined, in one individual, princi pally to one locality, it nevertheless appears to depend upon a vice pervading the entire venous system, the effects of which are more particularly called out in one locality by the existence of some mechanical excitant there present. I cannot at all agree with Hasse and Landouzy, " that the full development of this disposition in one locality prevents its out break in another." This doctrine has, how ever, been supported by a show of argument. Thus it may be truly said that hxmorrhoids, varicocele, and varicose subcutaneous veins very seldom exist together in the same indivi dual : the concurrence of either two of them is unusual, and much less frequent than their solitary development ; and moreover the dif ferent forms are met with, as a rule, in different classes of society : thus hmmorrhoids are most frequent in the affluent, varicocele in the sensual, and varix of the lower extremities in the labouring classes. Again, the different
forms appear at different periods of life, varicocele about orsoon after puberty; hmmor rhoids and other varix usually about man hood. But all these arguments fail, when it is recollected that in each of these suggested instances there is some special circumstance, which, acting as an excitant, superadded to a previous constitutional disposition, might ac count for the particular locality in which the disease makes its appearance, and the parti cular time at which it occurs. If in all these instances obstruction to the circulation cannot be made out, there is some cause of greater vascular activity, which is also seen to be efficient in the production of phlebectesis. Haemorrhoids are most frequent in the af fluent, because their mode of life leads to greater vascular activity in the alimentary canal, and to frequent portal obstruction : varicocele in the sensual, from the greater stress of blood upon the spermatic veins ; at puberty also, from the same cause : the la bouring classes likewise are afflicted with saphenous varix on grounds similarly expli cable. It is because there is particular em phasis laid on one particular organ in each of these eases that the specific form of phlebec tesis is assumed in the separate examples. And where such influences have been compound, other effects have followed, combining more or fewer forms of varix. It cannot therefore be said that one form of phlebectesis prevents another, or even diminishes the chance of its formation ; the truth is, that the same indivi dual is not liable to he exposed to the exciting cause of more than one form, that the pre disposing condition of the veins may be uni versal, but in one set alone is the morbid change called forth.* Phlebectesis may conveniently be divided into several forms. Andral has made the fol lowing division : " First species. Simple dilatation, unat tended by any other alteration, either affect ing the whole length of the vein, or existing only at intervals.
" Second species. Dilatation of the veins, either uniform or at intervals, with thinning of the parietes at the dilated points.