MANAGEMENT OF URETHRAL
STENOSIS
The subject of urethral stenosis
disease has undergone considerable change in regard
to etiology and therapy durir last 50 years. This page
has some approaches to the problem of stenotic posterior
urethra. These urethral stenosis almost totally result
from trauma, either secondary to an external force with
shearing of the urethra.Those involving the membranous
urethra only can be secondary to transurethral resection.
Urethral stenosis: The etiology
It is important to understand the etiology
of urethral stenosis, since post-infectious stenosis
generally is far more extensive than appears to be urethrographically
or cystoscopically. Trauma results in a more limited
set of circumstances and, there the outcome of repair
of post-traumatic strictures is (or should be) better
than the therapy of post-infectious stenosis.Both factors
may have a role in the causation of anterior urethral
stenosis secondary to transurethral resection and/or
indvwelling urethral catheters. Fortunately, the use
of silicone catheters and antibiotics has kept strictures
at a minimum following, much of the major cardiac, oncological
and reconstructive surgical procedures with necessary
urinary output monitoring. It goes without saying that
the analogue of the male posterior urethra in the female
subject is rarely the site of urethral stenosis.
Another factor is selecting treatment
for urethral stenosis is whether the stenosis
can be traversed by a filiform or a sound. If passable,
one should elect visual internal urethrotomy as initial
treatrnent. The procedure should be terminated if one
is unable to follow a catheter as a guide through the
urethral stenosis . Thus, tortuous stenosis or those
with false passages may not meet the criteria for visual
incision, although they may be of a reasonably large
caliber. A possible exception is the short prostatomembranous
stenosis.
Once inside the urethra, a deep incision can be made
at tl 12 o'clock position into a normal urethral wall
or periurethral tissue. Excessive depth or length of
cut into corporeal tissu usually with a high head of
irrigant pressure, can result i priapisrn, The erection
generally is brief, perhaps 2 hours in duration, but
it rnay persist for several hours. Rarely, priaprism
has been reported as a cause of impotence following
visua urethrotomy. Cessation of the procedure generally
is the bes policy if priapism develops early in the
dissection of a Ioni stricture.
Urethral stenosis: Mantainance of
an open urethra postoperatively
Equally important to adequate incision (28F in adults)
is the maintenance of an open urethra postoperatively.
We have found that self-catheterization daily with a
24F rubber catheter is the best way to ensure that the
urethral stenosis will not recur. Compliance has been
good and 4 to 6 weeks of catheterization postoperatively
generally is long enough. Panurethral stenosis, well
suited to visual urethrotomy, require more diligent
and longer followup. A second internal urethrotomy for
mild recurrent strictures is better than an open procedure
that requires several days of hospitalization and regional
or general anesthesia. Visual urethrotomy can be done
with the patient under local anesthesia on an outpatient
basis unless disease is extensive.
Urethral stenosis: Selection of the proper open procedure
Selection of the proper open procedure
for impassable stenosis repair is equally important.
In general, a single stage repair is adequate and preferable.
Direct anastornosis is the procedure of choice for post-traumatic
urethral stenosis less than 2.5 cm. Transpubic and perineal
approaches have their advocates. The results should
be equally good either way.
The major point of contention seems to be which open
procedure yields the best results in longer or post-infectious
urethral stenosis.
Although 2-stage repairs occasionally may be necessary
(severe infection, fistulas, multiple failures) a single
stage repair should yield quite satisfactory results
in the surgery for urethral stenosis. Either a free
or pedicìe full thickness skin graft will resolve
most remaining problems. Care should be taken to avoid
hair-bearing skin. The best results are obtained if
preputial or penile shaft skin is used. At all costs,
avoid infection, get a snug fit of well vascularized
periurethral structures to oppose the free graft and
leave a stent for 12 to 14 days.
Lastly, a pretty appearance postoperatively rnay be
more difficult to achieve than a satisfactory functional
result. Persistence of sterile urine and a good stream
postoperatively are the goals of treatment. Urinary
flow rates may be used for documentation if desired.
Calibration at annual intervals in asymptomatic patients
should be urged. The presence of residual urine postoperatively
usually indicates bladder outlet obstruction rather
than recurrent or persistent urethral stenosis disease.
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