PERINEAL LITHOLAPAXY. 237 



INDICATIONS. 



Various authorities recommend perineal litholapaxy under some or 

 all of the following conditions: 



(1) A large or very hard stone necessitating tlie use of a lithotrite wliich 

 will not pass easily by the natural route. 



(2) Stricture, in conjunction with a large or hard stone, or perhaps with any 

 stone. 



(3) A diflicult or narrow urethra. 



(4) Imperfect equipment — the absence of the smaller sizes of lithotrite. 



(.5) Cases in which litholapaxy has been commenced in the ordinary way, but 

 can not be completed satisfactorily owing to swelling of the urethra and deposit 

 of debris. 



THE OPERATION. 



Perineal litholapaxy may thus be performed : The patient is placed in the 

 lithotomy i^osition, and the thighs held so that the parts are as symmetrical as 

 possible. A curved staff with a median groove is introduced into the bladder 

 and held as in lithotomy, but neither drawn up beneath the pubes nor depressed. 

 The scrotum is allowed to hang down in the natural position, and neither the 

 operator nor the assistant steadies the skin. 



A very small incision, or stab, is now made with the point of a tenotomy 

 knife or double-edge scalpel, in children abovit one inch, in adults one and a half 

 inches in front of the anus, through the median raphe in the direction of the 

 staff; the groove is entered and the urethra incised for one-eighth inch or more 

 and the knife withdrawn, slightly enlarging the superficial part of the incision 

 as it emerges. The point of an ordinary director, which should not be too blunt, 

 is inserted through the wound into the groove of the staff, and passed into the 

 bladder ; the staff is withdrawn, and graduated female soiuids or Hegar's dilators 

 introduced up to the i-equired size. Some operators do not pass the dilators 

 so far as the bladder, but there is at all events no harm in doing so. 



Dilation is proceeded with slowly, and each instrument is left in position some 

 little time; when the required aperture has been attained the director is with- 

 drawn, leaving a circular, gaping orifice into the urethra. The appropriate size 

 of evacuating catheter is now passed, and the bladder injected, and the lithotrite 

 should follow without difficulty. 



If preferred, the director can be guided into the groove of the staff along the 

 knife, before the latter is withdrawn. Both cannula and lithotrite are entered 

 point downwards, and carried into the bladder by the usual rotatoiy movement. 

 The operation is completed in the same way as an ordinary litholapaxy, and as 

 a rule there is no difficulty in retaining fluid in the bladder; if leakage should 

 occur at the margins of the wound it is easy to conrpress them against the 

 instrument. 



In order to avoid a valvular aperture (which renders the introduction of 

 instruments difficult) it is most important that the skin should not be displaced 

 when making the incision. Also, it is better to enter the knife too far fonvard 

 than too near the anus; in the latter case the instruments enter the urethra at 

 an acute angle instead of vertically, and are much more likelj' to slip past the 

 opening, and there is the added difficulty of working in a deeper wound. Tlie 

 chief danger of the operation lies in the lithotrite or cannula missing the urethral 



