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Difficult Renal Stones
Bladder
Calculi
A bladder
stone, also referred to as vesical calculus, is predominantly a
disease of men. In the United States, bladder stones occur usually
in men over the age of 50 and are usually associated with bladder
outlet obstruction. The diagnosis of a bladder stone should result
in a complete urologic evaluation for factors that result in retention
of urine, including stricture of the urethra, benign prostatic hyperplasia,
diverticulum of the bladder, and neurogenic bladder.
In
contrast to renal stones, bladder stones are usually composed of
uric acid stones (see Figure a) in noninfected urine or struvite
stones (See Figure b) in infected urine.
Symptoms
In
patients with prostatic enlargement and residual urine, the complaints
may be those of prostatic obstruction, with the calculus being found
incidentally. Typical symptoms of bladder stone are intermittent,
painful voiding with terminal hematuria (blood at the end of the
urinary stream). Discomfort may be dull, aching, or sharp suprapubic
pain, which is aggravated by exercise and sudden movement. Severe
pain usually occurs near the end of micturition, as the stone impacts
at the bladder neck. Relief may be afforded by assuming a recumbent
position. The pain may be referred to the tip of the penis, scrotum,
or the perineum and on occasion to the back, the hip or even the
heel or sole of the foot. Besides pain, there may be an interruption
of the urinary stream from impaction of the stone at the bladder
neck or urethra. Priapism and nocturnal enuresis may occur in children.
Diagnosis
Bladder stones are not often seen on plain films because of the
presence of uric acid in many of the calculi and because of overlying
prostatic tissue. However, struvite stones, which are radiopaque,
may be seen on plain film (See Figure c). Ultrasonography is useful
for detecting radiolucent calculi. Cystoscopic examination is the
best method for detecting bladder stones.
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| Bladder
calculus. Plain abdominal film demonstrates densely opaque,
calculus in the pelvis (yellow arrows). Cystoscopy confirmed
the presence of a bladder stone. |
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