Transcript Radiography Of The GU System

Chapter 18
The Urinary System
9/9/10 Classroom ed.
Urinary System
• Often called the excretory system
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Two kidneys
Two ureters
One urinary bladder
One urethra
2 bean shaped bodies situated
behind peritoneum
Asymmetrical - left is slightly
longer and narrower than right
How come Rt kidney slightly
lower than Lt kidney?
Liver
Lie in an oblique plane (opposite
si jt direction)
Normally extend from T-12 to L3
Kidneys
Kidney Function
• Remove waste
products from blood
• Maintain fluid and
electrolyte balance
• Secrete substances
that affect blood
pressure
• How much urine
excreted per day?
1 - 2 liters
Kidneys (cont’d)
• Minor calyces unite to form
major calyces
• Major calyces unite to form
renal pelvis
• Renal pelvis then drains into
ureters
• Hilum - longitudinal slit in
medial border for transmission
of blood vessels, nerves,
lymphatic vessels, and ureter
Kidneys (cont’d)
• Essential microscopic
components of kidney
called nephrons
• How many nephrons
per kidney? about 1
million
Neprons
Collecting ducts
drain into minor
calyx
Adrenal Glands
Cannot be seen on plain
radiographs
Not part of urinary system
Chiefly responsible for
regulating stress
response through
adrenaline etc
Ureters
• Two tubes 10 - 12 “
long
• Retroperitoneal
• Extend from renal
pelvis
• Enter bladder at ureteral
orifice
• How is urine moved
through ureters?
– peristalsis
Urinary Bladder
• Musculomembranous
sac situated
immediately posterior
and superior to
symphysis pubis of
pelvis
• Serves as Urine
reservoir
Urinary Bladder
• How much fluid can
bladder hold?
– up to 500 mL
• Urethral orifice
located in bladder
neck
• Area between ureteral
openings and urethral
orifices is trigone
Urethra
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Carries urine from bladder to?
exterior of body
How long is it in females?
About 1.5
In males?
About 7 to 8
Sphincter at neck of bladder
controls flow
• Male urethra contains following
parts:
– Prostate
– Membranous area
– Spongy area
Prostate
• Gland surrounding
proximal part of male
urethra
• Considered part of male
reproductive system, but
due to location, often
described with urinary
system
• Prostate secretes fluid
that mixes with seminal
fluid to create ejaculate
Radiography of Urinary System aka
Urography
Radiographic investigation of renal drainage or
collecting system
IVU- Intravenous Urogram !
Formerly erroneously known as IVPIntravenous pyelogram!
– pyelo refers to renal pelvis and calyces only
– study also shows ureters, bladder, and
sometimes urethra
Indications For Urography
• Demonstrate physiologic function and structure
of urinary system
• Evaluate abd. Masses, renal cysts and tumors
• Urolithiasis (stones)
• Pyelonephritis (Inflammation of kidney)
• Hydronephrosis (distension of renal pelvis and calyces with urine)
• Effects of trauma
• Pre-op evaluation
• Renal hypertension
Contraindications
• Inability to filter contrast medium from
blood
• Allergy to contrast
• Abnormal BUN and Creatinine levels
Preparation Of Pt
• Pt should follow low residue diet for 1-2 days
prior to exam
• laxative taken day before
• NPO after midnight
• Pts with multiple myeloma, high uric acid levels,
or diabetes should be well hydrated before IVP
exam
– Dehydration leads to increased risk of renal
failure
Contrast Media
• Must be used to visualize
urinary tract
• Iodinated, water-soluble
contrast administered
intravenously to examine
system
• Antegrade filling
Contrast Media
• Excretory urography (IVU) generally uses a 50 to
70% iodine solution
• Lower concentrations for bladder studies due to
large amount required to fill bladder (30%)
• Non-ionic contrast is generally used
– More expensive, but– Patients less likely to have reactions with nonionic
Contrast Media and Adverse Reactions
• Crucial not to leave pt alone for first 5 minutes after
injection!
• Mild reactions
– warmth
– flushing
– hives, Nausea/Vomiting, respiratory edema
(accumulation of fluid in lungs)
• Severe reactions
– Anaphylactic shock
(sudden allergic response associated with a
sudden drop in blood pressure and difficulty breathing). Can lead to death in a
matter of minutes)
Injection Procedure
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Obtain allergy history
Explain exam to pt
Prepare contrast and supplies (sterile tech.)
Assist radiologist as necessary
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• Perform injection if IVcertified
Injection Supplies (cont.d)
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Tourniquet
IV arm board
Towels
Emergency kit
Emesis basin
Alcohol wipes, hibiclens, or povidone iodine wipes or swabs
Contrast
19-22 G needle, butterfly or angiocath for infusion
Extension tubing
Tape or clear-type dressing
IVU Procedure
• Scout – KUB
• Contrast is injected
• Timed sequence of films obtained until bladder
begins to fill– Immediate image of kidneys
– 5 minute image of abd. or kidneys
– Compression applied
Ureteral Compression
• Applied over distal ends
of ureters
• Inhibits flow of urine into
bladder
• Distends renal pelvis and
calyces
• Compression device
should be centered at
ASIS
Ureteral Compression
• As much compression as
pt can tolerate!
• Should not be applied
when:
– stones, abd. mass or
aneurysm, colostomy,
suprapubic catheter, recent
abd. surgery or trauma
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(Because of improvement of contrast
agents, compression no longer
generally used)
(cont’d)
IVU Procedure cont’d
• Tomograms are obtained
once bladder is filled
– Pt is measured, divide number
by 3, cuts begin there
• Pt. measures 30cm,
beginning cuts at 10cm
• Release compression slowly
• Have pt void, and obtain
post-void film
Radiation Protection
• Radiographer is responsible!
• Gonadal shield - if it does not interfere with
examination objective
• Close collimation
• Avoid repeat exposures
• Shield males for all urinary studies, except
when urethra is of primary interest
Radiation Protection
• Shield females when IR centered over
kidneys
• Rule out chance of pregnancy before
examination
(Emergency cases may not allow time)
Radiographic Positions IVU
AP Projection-IVU
• KUB
• (All exposures at end
of expiration for any
urinary system study)
AP Projection- IVU (cont’d)
Must include entire
KUB region
Should include
prostatic region on
older males
Time Delay - IVU
3 minute
6 minutes
Time delay- IVU
9 minutes
With compression
AP Projection Variations
• Trendelenberg
– Lower head 15 - 20 degrees
– Helps demonstrate lower ureters
• Upright
– Center lower - organs change position
• Prone
– Demonstrates ureteropelvic region
– Fills obstructed ureter in cases of hydronephrosis
(distension of renal pelvis and calyces with urine)
AP Oblique Projections - RPO/LPO
• Patient is supine
• Patient rotated to
30 degrees
• CR to iliac crest, 2
in. lateral to
midline
– Center to side up
AP Oblique Projections - RPO/LPO
• Elevated
kidney will be
parallel to
cassette
• Kidney
closest to
cassette will
be
perpendicular
• Entire KUB
region must
be included
Nephrotomography
• Best method for
visualizing renal
parenchyma (neprons and
collecting tubules)
• Ability to visualize
kidneys free of
intestinal content
superimposition
Retrograde Urography
What does
retrograde
mean?
Opposite normal flow
Retrograde Urography
• Considered an
operative procedure
• Pt may be under
general anesthesia
• Sterile technique is
used
• Nurse responsible for
set-up of exam and
pt. care
Retrograde Urography
• Requires
catheterization of
ureters
• Contrast injected
directly into
pelvicaliceal system
via cathethers
• Provides improved
opacification of renal
collecting system
Retrograde Urography
• Contrast does not enter
blood stream
• Used for patients with
renal insufficiency or
contrast sensitivity
• Ureters, and collecting
systems can be
selectively imaged and
sampled
• Little physiologic
information provided
(cont’d)
Cystography
Cystography
• Radiologic exam of
urinary bladder
• Contrast
administration usually
performed
retrograde (against
normal flow of urine)
Excretory Cystogram
Retrograde Cystogram
Cystography
Indicated for:
Vesicoureteral reflux (backward flow of urine into ureters)
Recurrent lower urinary tract infection
Neurogenic bladder: (dysfunction due to
disease of central nervous system or peripheral nerves)
Cystography indications cont’d
– Bladder trauma
– Prostate enlargement
– Lower urinary tract fistulae
– Urethral stricture
– Posterior urethral valves (obstructive congenital defect
of the male urethra)
Cystography
• Contraindications – anything
related to catheterization of
urethra!
“Retrograde”
Cystography
• Contrast will be dripinfused via a catheter
• Bladder will be filled to
capacity
• Fluoro-spot and overhead
films will be obtained
Cystography Routine Series
Scout
filled AP
both obliques
lateral
voiding
post-void
AP Axial Bladder
• CR( similar to coccyx projection)
– Angled 10 to 15
degrees caudad to
center of IR
– Enters 2 above
upper border of
pubic symphysis
AP Axial Bladder (excretory method)
PA Axial Bladder
(prone)
CR
– Angled 10 to 15 degrees cephalad
– Enters about 1”distal to coccyx
– Exits just above superior border of pubic
symphysisPatient prone
– Arms out of anatomy of interest
– IR centered to CR
AP Oblique Bladder
• Pt position
– 40- to 60-degree
– RPO or LPO
depending on
physician
preference
AP Oblique Bladder
CR
– Perpendicular to center of
IR
– CR 2 above upper border
of pubic symphysis and 2
medial to upper ASIS
– If bladder neck and
proximal urethra is of
interest, 10-degree caudal
angle of CR will project
pubic bones below them
Lateral Bladder
• Patient position
– Lateral recumbent,
right or left side
• Part position
– Knees flexed
– MCP aligned to
midline
• CR to midcoronal
plane at 2 in. above
symphysis pubis
Lateral Bladder
– Demonstrates
anterior/posterior
bladder walls
– Base of bladder
– Any vesicovaginal
or vesicorectal
fistulae
Cystourethrography
Cystourethrography
• Retrograde study to
visualize bladder and
urethra
• Contrast does not
enter blood stream
• Sterile technique
must be used
• Nurse will generally
perform
catheterization
Male Cystourethrography
• AP Oblique Projection - RPO/LPO
• Patient is supine, rotated 35 - 40 degrees
• Urethral syringe (or Brodney clamp?) is used to
introduce contrast
Cunningham Penile Clamp:
device used to help control
male urinary incontinence.
Male Cystourethrography
• Images are obtained as
contrast is injected
• Entire urethra must be
visualized
• Bladder can be filled to
obtain antegrade voiding
study
• Why is this antegrade if
its injected into urethra?
Female Cystourethrography
• Retrograde
• AP Projection (maybe obliques)
• Bladder can be filled and patient void for
antegrade studies
• Cassette should be centered as for
cystography
• Abduct thighs to prevent superimposition
of bone or soft tissue
Incontinence Studies
• Positioning is same as retrograde
cystography
• On lateral films, pt. asked to strain to
demonstrate any prolapse or incontinence
Metallic Bead Chain Cystourethrography
• To evaluate stress
incontinence in females only
• Beaded chain inserted in
Urethra
• Shows anatomic changes in
shape and position of
anatomic floor
• Valsalva tech. applied for
comparison
Voiding Cystourethrogram
X-ray images of bladder
and urethra during urination
Follows cystogram - urinary
catheter removed
Pt. urinates into special
radiolucent urinal as
images taken
Voiding Cystourethrogram
cont’d
• Shows size and shape of bladder under stress
caused by urination
• Demonstrates urethra functioning
• Most commonly used for young girls with history
of recurrent bladder infections
The End