Through an incision in the vas deferens just above the testicle (vasotomy), a solution of collargol or other metallic compound can be injected into vas and vesicle, and skiagrams made of these. Such pictures amplify our limited knowledge of the physiology and pathology of the vas deferens and seminal vesicle, and of the genital functions of the male.
The strength of the collargol should not exceed from 10 to 15 per cent.; the quantity injected at one sitting should in general be limited to 4 or 5 c.c.; injection should immediately cease if pain in groin or rectum occurs, since such pain shows irritation of vas or vesicle, sometimes requiring mitigation by morphin. If the vas be occluded by stricture, severe pain may be caused by the injection of even 1 or 2 c.c. Regurgitation of collargol into the connective tissue around the opening in the vas follows overdistention, and