The operation is facilitated by casting the animal and withdrawing the penis from the sheath, but as there is considerable danger of rupturing the bladder when casting an animal with marked distension of that organ, the more serious operation should be preceded by puncturing the urethra with a fleam at the ischial arch.
By repeated moderate traction on the extremity of the glans, the S-shaped curve can be obliterated and the anterior portion of the penis withdrawn beyond the sheath.
One of two conditions may exist.
First case. Where the calculus is in the anterior, extra-prepubic portion, it is removed through an incision made directly over it. After extraction and disinfection, one or two sutures are inserted.
Second case. Should the calculus be situated in that portion of the penis which remains within the sheath after the fullest withdrawal of the organ, it is necessary to proceed as follows:—
(1.) The skin covering the sheath, the subcutaneous tissue, and the mucous membrane are first incised for a length of from 1¼ to 1¾ inches.
(2.) The penis is drawn through this opening; an incision is made directly over the calculus, dividing the fibrous layer, erectile tissue and mucous membrane of the urethra; the parts are disinfected and the wounds closed with sutures.
With ordinary antiseptic precautions little danger is to be feared.
Even should infiltration of urine occur, the operator need not be unduly anxious, for, provided the parts are punctured or scarified early, recovery usually follows.