Cystography

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Unit 7
Cystography & Retrograde Urography
RDSC 233
Bontrager pp. 563-574
Radiographic anatomy
Film Critique
Positioning of:
Exposure Factors
AP cone down bladder
Oblique cone down bladder
Lateral cone down bladder
Voiding cystourethrogram (VCUG)
female
male
Injection urethrogram
Retrograde pyelogram
Radiographic
Pathology
What in the World?
Miscellaneous, but significant,
odds and ends
Routine IVU Positioning
Preparation
1. Evaluate the order
2. Greet the patient
3. Take History
What is pertinent Hx?
Bladder diverticula, rupture, CA,
incontinence, bladder infections,
outlet obstructions, vesicoureteral
reflux, postoperative anastomoses.
4. Remove jewelry, check attire, snaps, pins, NG tubes, etc.
5. Explain the exam in layman’s terms
6. Questions?
7. Set technique before positioning
Cystography
Cystograms are obtained in two basic ways.
1. As part of an excretory IVU. The three “cone down” views
may be incorporated in an IVU routine, or may be done on
request.
* When a patient having an IVU has a foley catheter in place,
drain the bladder before the injection, then clamp it.
* When working with a catheterized patient, do not raise the
bag above the level of the bladder.
2. As a retrograde cystogram. Contrast is instilled via a urinary
catheter. Unless there is reflux into the ureters, no other
urinary structures are seen.
Retrograde cystography
* Patients arrive with a urinary (urethral) catheter in place, or it is
inserted in radiography room, under aseptic conditions.
* The bladder is drained of urine and contrast is dipped under gravity,
never injected, or the bladder could be ruptured.
* The contrast is an iodine preparation of approximately 18-30%.
Common brands include: Cystografin, Cysto-Conray,
Hypaque-Cysto.
* Filling may be monitored under fluoroscopy, or films may be taken
at intervals during filling, such as 100, 200, 250, 300cc, etc.
The amount of filling is determined by patient comfort.
Routine AP bladder positioning
Setup for all cystograms
40” SID, 12:1 or 16:1 grid,
70-75 kVp for iodine, expose on
expiration.
Film size: 11”x14” lengthwise
for distal ureters (reflux on a
cystogram).
It is not unusual for 10”x12” or
8”x10s” to be used crosswise
instead, especially in
consideration of the centering.
AP position
1. Supine
2. 100-150 caudad angle
3. CR 2” superior to pubic
symphysis, midline
Critique criteria for AP bladder
The purpose of the caudad
angle is to project the pubic
bones beneath the floor of
the bladder.
All of the bladder is included.
If using an 11” x 14”, about
half of the ureters will visualize
should there be reflux.
Routine oblique bladder positioning
Oblique positions
1. RPO & LPO: 450-600
2. CR perpendicular
3. CR 2” superior to pubic
symphysis, and 2” medial
to the ASIS of the side up
Routine oblique bladder positioning
Phleboliths – Stones in veins.
Common in large division of
the iliacs around the pelvic floor.
Characteristics of the oblique
pelvis (1-3).
Suprapubic
catheter –
Used when
a urethral
catheter
cannot be
inserted.
2. In this RPO position the rami on the
right are superimposed, while the
obturator on the left is seen in profile.
1. AP – Obturator foramen are
symmetrical, symphysis pubis
is midline.
3. Also an RPO:
the left SI joint is
demonstrated, and
the left ala is
foreshortened
Critique criteria for oblique of bladder
The most shallow angled cystogram is
taken with a 14”x17” oblique of the
kidneys (IVU). The film shown here is
a 300 RPO, as evidenced by the
excellent demonstration of the left SI
joint
ASIS
Distance to bladder
is much greater than
2” in a shallow oblique
When the bladder is filmed alone,
45 to 600 is used. Notice the position
of the ASIS relative to the obliquity.
No specific structures are
demonstrated on the 450
oblique. All of the bladder
is included.
Critique criteria for oblique of bladder
The 600 oblique is
designed to demonstrate
the ureterovesicle (UV)
junction of the side up.
All of the bladder is
included, and the thigh of
the independent leg is not
superimposed on the
bladder
The above obliques
show diverticula at the
UV junctions. The AP
film is seen on the left
In a steep oblique position the ASIS
is close to the center of the bladder
Lateral bladder positioning (not routine)
Lateral position
1. True lateral position
2. CR perpendicular
3. CR 2” superior and 2”
posterior to pubic
symphysis.
Critique criteria for lateral bladder
The lateral demonstrates the anterior
and posterior walls of the bladder, and
parts of the superior and inferior aspects
not as well seen on the frontal views.
All of the bladder is included.
kVp will be above the optimal range,
and may need to be 90 or more in larger
patients. Quality will be compromised.
Increased scatter also lessens the value
of this view, and the gonadal dose is
higher.
For these reasons the lateral is
most often done on special request.
Voiding Cystourethrograms (VCUG)
female & male
In addition to being a cystogram, the VCUG s is a functional study to
examine the urethra for strictures, obstructions, diverticula, and reflux into
the ureters.
The patient may be recumbent or upright.
Filming may be done using a spot film camera, or overhead tube.
The bladder is filled retrograde via a urinary catheter (Foley). After filling
the bladder the retention balloon is deflated, and the catheter is removed.
The patient is instructed to begin urination into a radiolucent receptacle or
absorbent padding (chux) while filming.
Deflation
port
Foley urinary catheter. Retention balloon
is inflated with sterile water or NS.
Female Voiding Cystourethrogram (VCUG)
AP position
All of the bladder is included.
The entire urethra is seen
during micturition (micturate)
1. Supine
2. CR perpendicular
3. CR to pubic symphysis
Male Voiding Cystourethrogram (VCUG)
RPO
All of the bladder is included.
The entire urethra is seen
during micturition (micturate)
1. 300 RPO
2. CR perpendicular
3. CR to pubic symphysis
4. Superimpose urethra on
thigh to act as filter
Injection (retrograde) Urethrogram
male only
Injection urethrography is done when an obstruction hinders the
insertion of a catheter, or trauma prevents urination.
Brodney
Clamp,
(or catheter)
Extravasation of
contrast from
ruptured bladder.
Extravasate = escape out of, vs.
Infiltrate = passing, or forced into.
Retrograde Pyelography: female & male
Retrograde pyelograms are minor surgical procedures that are performed
is a “cysto room” that is often in the surgical suite.
Patients are sedated, or given general anesthesia.
A cystoscope is inserted by the urologist, and the visible interior of the
bladder is visually examined.
Ureteral catheters are advanced through the cystoscope, and the ureteral
orifice is catheterized unilaterally, or bilaterally, as indicated.
The lithotomy position
Used for urological procedures.
In the stirrups
Retrograde Pyelography: the filming sequence
ureteral
catheter
Scout
0900
cystoscope
#1
0907
3 to 5 cc of contrast is
injected by the urologist.
A scout film is taken to
A film demonstrating the
check the technique,
position, and placement renal pelvis and calyces
of the ureteral catheters. is taken
#2
0912
The urologist withdraws
the catheters and film
of the contrast filled
ureters it taken.
These three films are a typical routine, though more may be taken at the urologist’s
discretion. All films must be marked by the technologist: order and time.
Exposure Factors
75 kVp for optimal visualization of iodine contrast
All other technique computations are the same as
for the abdomen
1. 40-60% increase for oblique positions
2. 2x kVp (15% rule) and 2x mAs for lateral.
3. 25% increase of mAs when using 10”x12” for cone down views
Significant Pathologies
of the kidneys and bladder
and their
Radiographic Appearances
Calcified prostate
Renal calculi
Bladder stones
Cystocele
Hydronephrosis
Calcified Prostrate Gland
With age the prostrate gland
atrophies (atrophy), and sometimes
calcifies.
Both conditions lead to a narrowing
of the prostatic urethra and the
inability to completely empty
the bladder.
The surgical remedy is a transurethral
resection of the prostate (TURP)
Seen on these films is a severely
calcified prostate. Though rare,
bladder stones may look similar
on a plane film. On a cystogram
the calcifications are
seen to be in the prostate.
Bladder Stones
Once prevalent, stones in the
bladder are rarely seen today,
unless they pass from the
kidneys.
Stones that form in the bladder
are typically large and numerous.
Prior to the 20th century, bladder stones were a common malady that
were so painful, due to obstructions, people subjected themselves to
a procedure called “cutting for stones,” that was performed without
anesthesia, antibiotics, or aseptic techniques.
Cystocele
A hernia of the bladder, into
the vagina, caused by a
weakening of the vesicovaginal
fascia during delivery.
Causes urinary frequency,
urgency, and dysuria.
The cystocele on this upright
postvoid is completely below the
superior rim of the pelvic bones,
and would have been missed
with routine centering.
Renal calculi
Kidney stones are formed in the parenchyma, calyces, pelvis of the
kidneys. They may remain in place and be asymptomatic, or they come
loose and travel down the ureter.
Though often small, renal calculi
are sharp and jagged. They cut
the inside of the ureters which
are rich in sensory nerves,
causing intense pain. Hematuria
may be a sign of passing stones.
Lithotripsy is an alternative to
surgery that pulverizes stones
by using shock waves.
An obstructed ureter caused by a kidney
stone shows dilation of the ureter above
the obstruction, tapering to the lodged
calculus.
Renal calculi
Calculi in
parenchyma
A thin stream of contrast is
slipping by, seen to the UV junction. If the
pressure were not relieved the ureter would
continue to dilate.
Caculi filling large
parts of the calyces
are called staghorn
calculi
A similar example is seen on this postvoid
upright of the bladder. This delayed film
shows that excretion of contrast is
complete on the left, but a column of
contrast remains in the right ureter.
Hydronephrosis
When a ureter is obstucted from
calculi or other causes, urine (or
contrast) causes the renal pelvis
and calyces to dilate as long as the
kidney is functioning.
A build up of fluid in the collecting
system is hydronephrosis.
What in the World?
Miscellaneous, but significant, odds and ends
What in the World?
Review
What was this?
And these?
What in the World?
Guess what this is
What in the World?
A stent is a device that holds
tissue in place, or holds open
a hollow organ or vessels.
These ureteral stents create an open channel from the renal pelvis to
the bladder, to bypass and obstruction.
What in the World?
A percutaneous renal
puncture is performed
under fluoroscopy. A
needle is inserted into
a calyx, or the renal
pelvis.
A catheter is inserted
into the collecting system
for access to the kidney.
This procedure is
called a nephrostomy.
What in the World?
An ectopic kidney is one that is
in an abnormal position.
In this case it is a transplanted kidney.
Transplants are turned backwards,
and placed in the pelvic cavity. The
renal artery and vein are sutured to
the iliac vessels.
Adding a kidney, rather than replacing
one, often results in a damaged
kidney regenerating its function.
What in the World?
A pelvic mass, seen
by displacement of the
bladder.
38. Excretory urograms are antegrade studies of the kidneys, ureters,
and bladder. Cystograms (not IV injection) are
studies
of the bladder.
39. When urine (or contrast) from the bladder, flows back into the
ureters, this condition is called
.
40. What is the angle and direction of the CR for an AP cone down
view of the bladder?
41. What is the range of obliquity for the RPO and LPO of the bladder?
42. What specific anatomy will a steeper oblique demonstrate?
38. Excretory urograms are antegrade studies of the kidneys, ureters,
and bladder. Cystograms (not IV injection) are retrograde studies
of the bladder.
39. When urine (or contrast) from the bladder, flows back into the
ureters, this condition is called reflux.
40. What is the angle and direction of the CR for an AP cone down
view of the bladder? 10-150 caudad
41. What is the range of obliquity for the RPO and LPO of the bladder?
45-600
42. What specific anatomy will a steeper oblique demonstrate?
The ureterovesicle, or, ureterocystic junction.
43. What is the name, and acronym, for a functional study of the
bladder and urethra?
44. What is the term that describes contrast media that has
escaped from (out of) the bladder, due to a leakage or rupture?
45. What physician (
Oblique position
degree of obliquity
RAO stomach
40 asthenic -70 hyper
what is demonstrated
profile view “GI”
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