THE MALE EXTERNAL GENITALS. 



The urethra contains small mucous glands opening on its surface glands of 

 Littre and small pockets or recesses, called the lacuna of Morgagni, into which 

 the glands of Littr6 sometimes empty. The lacunae are mostly in three rows on the 

 roof of the penile portion and open forward toward the meatus. A large one 

 lacuna magna opens in the posterior portion of the roof of the fossa navicularis, a 

 couple of centimetres behind the meatus. The glands of Cowper open into the bul- 

 bous urethra just in front of the triangular ligament. The racemose glands of the 

 prostate open into the sides of the floor of the prostatic urethra, and the ejaculatory 

 ducts open near the middle line just in front of the urethral crest (verumontanum), 

 with the utricle (prostatic sinus) between. 



The mucous walls of the urethra are normally in contact, making a vertical slit 

 at the external meatus, a transverse one in the penile portion, horseshoe shape in the 

 prostate, and again transverse just before the bladder is reached. 



Urethral Muscles. There are two sets of muscles in connection with 

 the urethra; one set might be said to aid in expelling the urine and the other 

 in retaining it. The expulsors are the longitudinal and circular fibres surrounding 

 the urethra just outside the mucous membrane and the accelerator urina or 

 bulbocavernosus muscle. The sphincters are the compressor urethra or external 

 sphincter muscle, and the internal sphincter at the neck of the bladder, composed 

 of fibres continued from the bladder and prostate. The portion of these fibres 

 surrounding the internal meatus just beneath the mucous membrane is called the 

 annulus urethralis. 



It has been supposed that if the bladder becomes distended the internal 

 sphincter involuntarily relaxes and allows the urine to enter the prostatic urethra, 

 and it is then stopped by the voluntary contraction of the external sphincter, which is 

 the true sphincter. Leedham Green {Brit. Med. Jour., August, 1906) claims that 

 the internal sphincter holds tight in the living subject even when the bladder is over- 

 distended. Sections made of formalin-hardened bodies seem to support this view. 



Practical Applications. A knowledge of both the length and calibre of the 

 urethra is essential in the use of both catheters and bougies or sounds. If urine 

 begins to flow when a catheter is introduced 20 cm. we know the urethra is of normal 

 length. Urine may flow when the bladder is distended as soon as the catheter passes 

 the membranous portion, about 17 cm. (6^ in.) from the meatus. In hypertrophy 

 of the prostate the prostatic urethra is much increased in length and it may be impossi- 

 ble to reach the bladder by an ordinary catheter. It may require one 25 or 30 cm. 

 (10 to 12 in.) long. The position of a 

 stricture is located by its distance from the 

 meatus. If a sound is stopped by a stricture 

 inside of 15 cm. (6 in.) from the meatus we 

 know it is anterior to the triangular liga- 

 ment. Strictures are most frequent where 

 the subpubic curve is lowest, viz., at the 

 bulbomembranous region. They are then 

 called deep strictures. They are next most 

 frequent toward the anterior portion, while 

 strictures of the prostatic portion are almost 

 unknown. 



Passage of Sounds and Catheters. 

 In passing a catheter or sound its beak 

 should be kept applied to the roof of the 

 urethra, otherwise its point will catch in 

 the dilated bulbous portion and strike on 

 the triangular ligament below the opening 

 for the urethra. To aid the beak to follow 

 the subpubic curve the handle is depressed. 

 In difficult cases the index finger of the opposite hand is introduced in the rectum 

 and the beak is felt at the membranous portion a short distance in front of the apex 

 of the prostate and guided upward into the bladder (Fig. 474). If the penis is 

 grasped near the glans and drawn up the instrument, the urethra may so stretch 



FIG. 474. Method of passing the sound. The in- 

 dex finger in the rectum is guiding the sound through 

 the membranous urethra. 



