VAEICOCELE. 283 



sectional area of the veins. Moreover, the veins are tortuous, 

 and have many inter-communications, and there is possibly some 

 pressure exercised upon them by the action of the muscular 

 fibres forming the roof of the inguinal canal. 



The greater liability of the veins of the left side to be affected 

 is often attributed to the following anatomical reasons. The 

 entrance of the left spermatic vein into the left renal vein at a 

 right angle, and the rush of blood from the kidney across the 

 mouth of the spermatic vein are supposed to produce an 

 obstruction to the upflow of the spermatic blood. This is dis- 

 tinctly questionable, for this cross current may act in the opposite 

 way, namely, to create a species of suction. The left testis 

 usually hangs lower than the right, and the left spermatic vein 

 terminates higher than its fellow, but the difference in length 

 between two venous channels is not sufficiently great to make 

 it a marked predisposing cause of left varicosity. The left vein 

 has the last portion of the sigmoid flexure in front of it, and in 

 cases of severe constipation it may be that pressure is brought to 

 bear on the vein by hard scybalous masses. 



The true reasons probably for the frequency of varicocele on 

 the left side are that the veins in the left cord are usually larger 

 than those in the right, and there appears to be a persistence of 

 numerous foetal veins on the left, veins which disappear early in 

 life on the right side. 



In exposing the spermatic veins for their ligature, for the 

 relief of varicocele, the vas closely accompanied by its artery and 

 veins will be readily demonstrated lying deep to the spermatic 

 vessels in the posterior part of the cord. The spermatic artery 

 cannot as a rule be distinguished, and is probably usually ligated 

 with the veins. 



After ligature of the spermatic veins the blood from the testicle 

 is chiefly returned through the deferential veins, passing eventually 

 into one of the vesical plexuses. 



