The voiding cystourethrogram is an x-ray exam used to evaluate the lower urinary tract. It involves inserting a catheter into the bladder and filling it with contrast dye before taking x-rays during urination. It can detect conditions like vesicoureteral reflux, bladder abnormalities, and issues with the bladder outlet. The document provides detailed information on how the exam is performed, what is evaluated, common findings, and examples of various normal and abnormal results.
2. The voiding cystourethrogram is
a dynamic test used to
demonstrates the lower urinary
tract and helps to detect the
existence of any vesico-ureteral
reflux, bladder pathology and
congenital or acquired anomalies
of bladder outflow tract. It is
performed by passing a catheter
through the urethra into the
bladder, filling the bladder with
contrast material and then taking
radiographs while the patient
voids.
3. Indications:
Children:
Urinary tract infection– Usually done after some weeks of acute
stage or may be done under antibiotic converge. MCU is indicated
after the 1st occurrence of UTI in boys or girls.
voiding difficulties :
dysuria ,
thin stream dribbling,
frequency, urgency ,
vesico ureteric reflux,
trauma.
Baseline study prior to lower UT surgery.
Adults:
Trauma to urethra, urethral stricture, urethral diverticula ,UTI,
Reflux nephropathy prior to renal transplant of one/both kidneys.
4. Contrast Media:
Urograffin 60% used which is diluted with normal saline in 1:3.
The estimated volume of contrast medium to be given
during the examination is determined mainly by the age of
the child except for children less than one year of age in
whom it is determined by weight.
Less than one year,
Weight (kg) × 7 = capacity (ml)
Less than two years,
(2 × age in years + 2) × 30 = capacity (ml)
More than two years,
(Age in years/2 + 6) × 30 = capacity (ml)
5. Filming:
Once the contrast is instilled, fluoroscopic
screening is performed to see vesicoureteraic
reflux or other abnormalities. Patient is turned
oblique to ensure minimal reflux is not over
looked. If reflux appears , oblique films are
taken. If the bladder appears normal, one film
is taken in frontal projection at the end of
filling. At the end of voiding a frontal film is
taken of entire abdomen including kidney to
prevent overlooking the vesicoureteric reflux
which is seen only on termination of voiding
and may reach upper collecting system.
6. Adult Male:
The voiding study can be modified by
getting the patient to void against resistance
by using a penile clamp or compression of
distilled part of penis, which enhances
visualization of urethra by the artificial
distension.
.
This is known as choke cystourethrography
7. Complications:
UTI,
Adverse reactions may result from absorption of
contrast medium by bladder mucosa.
Catheter trauma causing dysuria, frequency
hematuria and urinary retention
perforation by the catheter or from over distention
Catheterization of vagina or ectopic ureteral orifice
Radiation effect: MCU is a diagnostic procedure that
inevitably exposes gonads to some radiation. It
should be kept to a minimum. Careful attention to
ensure very short screening periods. Tightly
collimated X-ray beam.
8. Several films are taken
when performing a
VCUG. The first
image is a KUB called
the scout film. On this
film one can evaluate
the spine and pelvis
(injury or congenital
anomaly such as spina
bifida) and the soft
tissues (calcifications,
foreign bodies, etc.).
9. Several seconds after the contrast material begins to flow,
the minimally filled bladder is imaged in the
anteroposterior projection. A ureterocele or bladder tumor
that is well seen during early filling may become obscured
as more contrast material enters the bladder.
On complete filling ,the bladder should appear smooth
and regular and there should be no filling defects. The
edges of the bladder image should be smooth.
10. Images captured during voiding will
demonstrate the urethra (strictures or
obstruction) and the bladder, and they will
document the presence or absence of
vesicoureteral reflux Unless there is a voiding
film, one cannot determine whether the patient
has reflux because reflux may only occur with
the pressure generated by voiding.
11. This film shows a
normal male
urethra; there is no
obstruction. The
variation seen in
the diameter of the
urethra is normal.
Indentation at the urethral
sphincter (normal)
12. • The post-void image may
demonstrate reflux
(contrast seen in the
ureter or kidney) or
extravasation of urine
from the bladder or
urethra (such as from a
traumatic rupture).
• No reflux and no residual
bladder urine is seen in
this normal post-void
film.. Normal post-void film
13.
14. A ureterocele is a congenital
abnormality found in the urinary
bladder. In this condition the
distal ureter balloons at its
opening into the bladder,
forming a sac-like pouch.
Prenatal diagnosis:
Hydroureteronephrosis
A cystic structure in the bladder
Oligohydramnios
18. Anterior urethral
stricture.
Oblique voiding
cystourethrogram of
the posterior urethra
poorly depicts a
stricture, which is
seen near the edge
of the image .
19. Posterior urethral valves.
Oblique voiding
cystourethrogram shows a
filling defect in the urethra with
a marked change in urethral
caliber at the level of the
defect, a finding that indicates
obstruction. The secondary
changes crucial to the
diagnosis—trabeculated
bladder, abnormally prominent
bladder neck, and dilated and
elongated posterior urethra—
are clearly depicted .
22. Urachal remnant, posterior
urethral valves, and reflux.
Oblique VCUG demonstrates
a large urachal remnant
extending from the superior
aspect of the small-capacity
bladder. Reflux, which is
reported in about one-third of
children with posterior urethral
valves, is also present .
Although the valve is clearly
seen (arrow), the secondary
changes are not well
developed due to aberrant
micturition into the urachal
remnant and ureter.
23.
24. On an anteroposterior
voiding
cystourethrogram, the
diverticulum is not
visualized.
Oblique voiding
cystourethrogram
demonstrates a
posterolateral bladder
diverticulum.
25. Pseudoureterocele.
Anteroposterior voiding
cystourethrogram shows a
collection of air on the left
side producing a filling
defect (arrowheads). The
air was introduced into the
bladder via a catheter. Air
can also simulate tumor or
blood clots.