Page 9 - Urological Health

The cause of this post-void dribbling is not perfectly clear, but is likely due to one of a couple of
reasons. The first might be that the sluggish urinary flow that many men experience (see the Lower
Urinary Tract Symptoms chapter for details) can result in a small pool of urine that becomes trapped
in the urinary passage (the urethra) at the end of the stream, without the force to be expelled into the
toilet. The urethra is shaped in such a way that there can be some retention of urine below the muscle
that closes the bladder’s outflow (see the Anatomy chapter). As you leave the bathroom, this small
pool of urine is shaken and dribbles out. If a man consciously stops his urinary stream before being
completely empty, a small amount of urine will leave the bladder but be stopped by this muscle
contraction a few centimeters downstream.When this muscle relaxes somewhat in the next couple of
minutes, this urine will slip out and leak, causing the sensation of a small squirt of urine in the
underpants.
If the urine flow simply peters out very slowly, but not after leaving the toilet, the same slow stream
that is common in men may be the cause. The limited flow through the urethra creates a dribbling
stream that can seem to take ages to stop. This is called terminal dribbling.
In women, the urethra is short and straight, and so cannot contain any urine after voiding. If you
dribble after voiding, it may be due to some weakness of the muscles of the pelvis that happens
commonly to women (please see the Urinary Incontinence chapter for details) and allows some urine
to leak. More rarely, there can be a small cavity that pouches out from the urethra, called a urethral
diverticulum,whichcan hold and occasionallyleak urine. This phenomenon is often associated with
UNDER REVIEW
urinary infections and discomfort during urination or sexual activity.

5. My doctor says I need urodynamic studies.

What are these and why do I need them?

Sometimes your urination problems cannot be pinpointed to one specific cause or diagnosis. In these
cases, special tests called urodynamic studies can be used to get more information. The most
common are the uroflow, multichannel urodynamics and videourodynamics.
You may need urodynamic testing:

• To assess the causes of urinary leakage (whether the bladder itself or the supporting
tissues around the bladder are the cause);

• To determine whether there may be a neurological problem contributing to your bladder
issues; or

• To determine whether sluggish urination is due to a weakened bladder or an obstructed
bladder outlet (difficult in passing urine from the bladder to the urethra).

1. Uroflow and post-void residual studies (measuring the volume of urine left in
your bladder after voiding completely) involve voiding into a special toilet to
measure the rate and volume of your urine flow. These can tell whether the flow
is truly weakened, or whether it shows evidence of straining to void or start-and-
stop voiding. After this, a bladder scan can be used to estimate whether the
bladder has truly emptied.

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