INJURIES OF THE URETHRA. 
377 
is healed. The greatest care is necessary during the first few days ; 
after granulations have formed, infiltration of urine is less likely to 
occur. Injuries produced by the catheter must also receive close 
attention. If during the first twenty-four hours great swelling and 
retention of urine result, urethrotomy or puncture of the bladder may 
become necessary to prevent rupture. Foreign bodies should be removed 
as soon as possible from the urethra, and the injury they may have caused 
treated according to existing circumstances. 
When urine has infiltrated the tissues, careful provision must he 
made for its exit, either by inserting setons, or, better still, drainage-tubes. 
Scarification may be of assistance. 
Though strictures of the urethra may be dilated by passing the catheter 
or a bougie, and urination thus assisted, the effect is seldom permanent, 
and the method not of practical value. Nor is urethrotomy much more 
reliable. In large animals it may temporarily relieve the difficulty, but 
new strictures soon form. Strictures near the free end of the urethra 
may sometimes be cured by freely laying them open. 
Urethral fistula is caused by an injury healing incompletely, and 
leaving a little opening in the wall of the urethra, through which urine 
is from time to time discharged. It may sometimes be closed by 
applying irritants or the actual cautery; but often it gives much trouble 
to the practitioner, and ends by producing stricture of the urethra. 
Moussu saw such cases in dogs after injuries to the urethra. Frohner 
improved the appearance of a horse suffering from urethral fistula by 
performing urethrotomy at a point above the fistula where there had 
been a dilatation of the canal. Urine was afterwards discharged by the 
artificial opening. 
» 
Y.—PARALYSIS OF THE URINARY BLADDER (CYSTO- 
PLEGIA). CATHETERISM. 
Long-continued retention of urine, due sometimes to urethral calculus, 
causes over-distension of the bladder, paralysis of the detrusor urinae, 
and inability to eject the urine. 
Paralysis of the sphincter vesicae produces involuntary discharge of 
urine (enuresis, incontinentia urinae). Not infrequently retention and 
involuntary discharge exist together, e.g., in severe internal diseases, 
puerperal apoplexy, brain diseases, haemoglobinuria, &c. In severe 
internal complaints, like post-partum paralysis, brain disease, haemoglobin¬ 
uria, and in diseases of the spinal cord and fractures of the dorsal and 
sacral vertebrae, paralysis of the bladder may occur, and is sometimes 
associated with paralysis of the tail and paraplegia. Calculi and gravel 
may also produce paralysis of the urinary bladder. 
