Ii6 



URETHROTOMY. LITHOTOMY. 



drawn easily and without much resistance through the neck 

 of the bladder. 



If the stone is so large that it cannot pass the neck of the 

 bladder lithotripsy may be performed. This operation re- 

 quires time and patience, since as a rule it is not possible to 

 encompass the entire calculus with the forceps. That is, 

 the narrowness of the neck of the bladder prevents the 

 sufficiently wide opening of the forceps. The stone con- 



Fig. 11. 



Urethrotomy (life size), /r, skin; a, retractor penis muscle; 

 /), bulbo- cavernous muscle ; r, spongy urethra ; //, urethra ; 

 k, catheter. 



sequently must be gradually broken off at its periphery and 

 the individual pieces of calculus removed. The character 

 of the surface of the stone has an evident bearing upon the 

 practicability of lithotripsy. 



The surgical dilation of the pelvic urethra with the 

 lithotome is usually far more practical than the crushing of 

 the stone. Introduce the instrument and divide the urethra 

 upward on the median line as the instrument is withdrawn. 



