Diseases and aceidents.—Dilated urethra is not uncommon as the consequence of stric ture. When the bladder is unable to get rid of its contents, the inordinate efforts to overcome the resistance occasion sometimes a gradual dilatation of the urethra behind the seat of stricture. This condition is at tended with excessive irritation along the whole course of the canal, and the prostate gland becomes hypertrophied in consequence. Sir Benjamin Brodie mentions a remarkable case of this description. In this case the urethra, behind the obstruction, was so di lated, that, whenever the patient attempted to pass his urine, a fluctuating tumour, as large as a small orange, was felt in the perinmum. It was punctured, and immediately the urine gushed out in a full stream.
The escape of .calculi from the bladder often occasions dilatation of the urethra into pouches ; and such dilatations occur inde pendent of ulceration.
On dissection of these pouches, the mucous membrane is usually found injected and thickened, presenting fungous vegetations, and occasionally coated with lymph.
The urethra deviates frequently from its normal direction : thus, in large scrotal hernim, and hydroceles of large size, it takes a ser pentine course: so also, when tumours press on the canal, its course is altered. The same happens in enlargement of the prostate gland, and from the projection of its middle lobe, the urethra divides itself into two streams. Abscesses also distort the canal from its na tural direction. Tumours in the pelvis, as a collection of hydatids between the bladder and rectum, in consequence of the influence they exert on the bladder, frequently distort the urethra from its normal direction. This dis tortion occurs more especially to the pelvic part of the canal. Under these circumstances the urethra is generally lengthened to a greater or less extent.
Solutions of continuity result either from mechanical injury, or from disease. The urethra may be wholly or in part divided. Most commonly, if the division be incomplete, a small fistulous opening remains for a short time, which subsequently, if let alone, com pletely closes. Incisions through the mem branous part of the urethra, as in the opera tion of lithotomy, speedily cicatrise.
The most serious injuries to the urethra are those resulting from blows or falls on the perinmum, especially when they are accom panied by fracture of the ossa pubis. In these cases there is either partial or complete solu tion of continuity. The membranous part of the urethra, from its position beneath the pubic arch, most frequently suffers. The na
ture of the injury may be generally recognised by the escape of blood with the urine, or by complete retention of urine. An elastic ca theter, carefully introduced, will in the former case generally rate against the torn part In complete division of the urethra, if the patient survive the injury, the torn ends are, in the progress of the cicatrisation and con traction, brought into apposition, and the con tinuity of the tube is restored : stricture is the almost necessary consequence. lf, how ever, the cure is not accomplished, urinary fistula is the unfortunate result. When the complete division of the urethra is accom panied with fracture of the pubis, the two ends of the canal are frequently so completely separated, that extensive extravasation of urine ensues, and the case is generally fatal.
Severe contusion of the urethra, inde pendent of rupture, sometimes leads to ul ceration or sloughing, and occasionally gives rise to stricture by inducing chronic inflam mation of the injured part.
Laceration of the urethra occasionally hap pens from the introduction of foreign bodies, or from the escape of fragments of calculi, especially after the operation of lithotrity. The torn part generally heals under simple treatment, or the urine is infiltrated into the spongy body, and abscess is the consequence. Laceration often attends violent efforts to force a stricture with the sound or catheter : these injuries usually happen at the under part of the canal, and frequently heal if all violence be desisted from. In a case of la cerated urethra brought into the London Hospital, a large pouch as big as a small orange was formed in the scrotum, into which, when the man attempted to micturate, the urine was forced ; he then squeezed it through the natural passage. By degrees this pouch gradually contracted, and no vestige of it remained.
inflammation of the urethra, whether com mon or specific, is usually of the catarrhal form : common inflammation is comparatively rare ; but it may be excited by chemical and mechanical stimuli, or it may depend entirely on constitutional indisposition : thus strong injections have been known to induce every symptom of severe urethritis simulating an attack of gonorrhoea; but the disease is speedily arrested by ordinary antiphlogistic treatment. Under the head of mechanical causes may be enumerated the introduction of the catheter or boogie, and other foreign bodies, and the passage of calculi entire or in fragments, and blows on the perinmum.