1044 SURGICAL ANATOMY OF THE PERINEUM. 



of urine, which, after the operation, continues for a time to trickle from 

 the bladder. But the prostate and the neck of the bladder, on the con- 

 trary, are to be incised only for a small extent. The reasons for this rule 

 may be stated as follows. By accumulated experience in operations on the 

 living body, it has been found that the structures now under consideration, 

 when slightly cut into, admit of dilatation, so as to allow the passage of a 

 stone of considerable size, and that no unfavourable consequence follows 

 from the dilatation. Moreover, when these parts are freely divided (cut 

 through), the results of lithotomy are less favourable than in the oppo- 

 site circumstances. The less favourable results adverted to appear to be 

 due to the greater tendency to infiltration of urine in the subserous 

 tissue of the pelvis ; and the occurrence of this calamity probably depends 

 on the fact that, when the prostate has been fully cut through, the 

 bladder is at the same time divided beyond the base of the gland, and 

 the urine then is liable to escape behind the pelvic fascia (which it will 

 be remembered is connected with both those organs at their place of 

 junction) ; whereas, if the base of the gland should be left entire, the 

 bladder beyond it is likewise uninjured, and the urine passes forwards 

 through the external wound. 



The steps of the operation by which the foregoing general rules are sought 

 to be carried out are the following. The grooved staff having been passed 

 into the bladder (and this instrument ought to be of as large size as the 

 urethra will admit), and the body or the patient, as the case may be, having 

 been placed in the usual position by which position the perinseurn ia 

 brought fully bafore the operator with the skin stretched out the first 

 incision is begun about two inches before the anus, a little to the left of the 

 raphe of the skin, and from this point it is carried obliquely backwards in a 

 line about midway between the tuber ischii and the anus, extending a little 

 way behind the level of the latter. During the incision, the knife is held 

 with its point to the surface, and it is made to pass through some of the 

 subcutaneous fatty layer as well as the skin. Now, the edge of the knife 

 is applied to the bottom of the wound already formed, in order to extend 

 it somewhat more deeply ; and the forefinger of the left hand is passed firmly 

 along for the purpose of separating the parts still farther, and pressing the rec- 

 tum inwards and backwards out of the way. Next, with the same finger passed 

 deeply into the wound from its middle and directed upwards, the position 

 of the staff is ascertained, and the structures still covering that instrument 

 are divided with slight touches of the knife, the finger pressing the while 

 against the point at which the rectum is presumed to be. When the knife 

 has been inserted into the groove of the staff (and it reaches that instrument 

 in the membranous part of the urethra) it is pushed onwards through the 

 prostatic portion of the canal with the edge turned to the side of the 

 prostate, outwards, or, better, outwards with an inclination backwards. 

 The knife being now withdrawn, the forefinger of the left hand is 

 passed along the staff into the bladder. With the finger the parts are 

 dilated, and with it, after the staff has been withdrawn, the position of 

 the .stone is determined and the forceps is guided into the bladder. 



In case the calculus is known to be of more than a moderate size, and the 

 knife used is narrow, the opening through the side of the prostate may be 

 enlarged as the knife is withdrawn, or the same end may be attained by 

 increasing the angle which that instrument, while it is being passed onwards, 

 makes with the outer part of the staff. And if the stone should be of large 

 size, it will be best to notch likewise the opposite side of the prostate before 



