402 SURGICAL APPLIED ANATOMY. [Chap. xvm. 



entirely block the orifice of the urethra. If the 

 affection be general, the prostatic urethra is lengthened, 

 and if one lateral lobe be more enlarged than the 

 other, the canal deviates to one side. When the 

 enlargement particularly affects the middle lobe, the 

 prostatic urethra, which is normally almost straight, 

 becomes considerably curved, the curve being some- 

 times very abrupt. 



It is important to note that enlargement of the 

 middle lobe alone can hardly be made out by rectal 

 examination. 



The severity of the symptoms in a case of 

 hypertrophy of the prostate bears little or no relation 

 to the the apparent size of the gland as felt per 

 rectum. A portion of the enlarged body may pro- 

 ject into the bladder. This usually takes the form 

 of a projecting middle lobe which, when viewed from 

 the interior of the bladder, may appear as a distinct 

 well-rounded pedunculated or sessile growth. 



In the operation of prostatectomy this projecting 

 and most troublesome mass is removed through a 

 suprapubic incision. Between the prostate and its 

 capsule is an extensive plexus of veins, the prostatic 

 plexus, into which enters the dorsal vein of the penis. 

 Phleboliths are said to be more frequently met with 

 in these veins than in any other in the body. This 

 plexus is cut in lateral lithotomy, and it is through 

 its vessels that septic matter is probably absorbed in 

 cases of pyaemia following that operation. 



The male urethra is about eight and a half 

 inches in length (21 cm.), an inch and a quarter being 

 devoted to the prostatic urethra, three-quarters of an 

 inch to the membranous, and six and a half inches 

 to the penile or spongy portion. Between the ages of 

 four and six years its length is 8 to 9 cm., and between 

 ten and thirteen years 10 to 11 cm. The canal may 

 be divided into a fixed and movable part. The fixed 



