Decline in use of IVU
Development of newer imaging modalities –USG, CT Scan, MRI
Adverse effects of contrast media
Cost
Indications
In Adults
Investigation of persistent or frank hematuria
Renal /ureteric calculi (prior to endourological procedure)
Complex urinary tract infection (including Renal TB)
Ureteric fistulas and strictures
Suspected transitional cell carcinoma
In Children
Evaluation of VATER anomalies
Malformation of genitalia –Hypospadiasis
Enuresis
Constant or intermittent dampness in girls to rule out ectopically
inserted ureter.
Contraindications
Absolute
Past history of severe adverse reaction to contrast media
High osmolarcontrast media(HOCM)-20% risk
Low osmolarcontastmedia(LOCM)-5% risk
Proven hypersensitivity to iodine
a serum creatinine level above 200 micromol/l would indicate a patient
who is unlikely to excrete contrast satisfactorily
should be cautious in diabetics and in patients with severe disturbance of
kidney function
Classification of iodinated contrast media
Water-soluble
High osmolality contrast media(HOCM)
-Diatrizoatesodium/meglumine(Gastrografin, Cystografin)
-Iothalamatesodium/meglumine(Conray, Cysto-Conray)
Low osmolality contrast media(LOCM)
-Iopamidol(Isovue)
-Iohexol(Omnipaque)
-Iopromide(Ultravist)
Iso-osmolalcontrast media (IOCM)
-Iodixanol(Visipaque)
Water-insoluble
Ethiodizedpoppyseedoil(lipidol)-embolotherapy/sclerotherapyand HSG
Patient Preparation
Bowel preparation
abdomen should ideally be free of radio-opaque fecal matter and gas
no food for 4-6 hour prior to examination
laxatives at bed time for 2 days prior to procedure
is now generally regarded as unhelpful and is unpleasant to the patient
Fluid deprivation?
Traditionally, practiced prior to IVU in order to improve opacification of
collecting system
Associated with increased risk of nephrotoxicity more in DM, Multiple
Myeloma, Hyperuricemia, Sickle Cell Disease and pre-existing renal disease
Modern non-ionic contrast agents do not provoke an osmotic diuresis,
degree of opacification is unlikely to be significantly altered by dehydration
Fluid restriction should be avoided and if there is a risk that the patient is
dehydrated before the IVU, this should be corrected first
Radiation protection
If whole of renal tract is to be visualized no gonad shielding possible for
the females
testis can be protected by placing a lead sheet over upper thighs
below lower edge of pubic symphysis
When bladder and lower ureters are not included, female can also be
given gonad protection
Technique
Informed consent
Median ante-cubitalvein
-contrast injection site
-cannulatedwitha 18-20 G needle and kept during entire procedure
IV cannula in place
-provides ER treatment if required
-for further injection of contrast if opacificationis inadequate
Most adverse reactions likely to occur within few minutes after injection
Emergency drugs (eg. Adrenaline,Hydrocortisone,Atropine), Oxygen and
Resuscitation equipment should be available in the procedure room
Classic series of films
Preliminary post void full length film -control film
Immediate film-Nephrogram
5-min film
15-min compression film
15-min release film
Post-micturition film
Stereotypical appearances of normal IVU
Takes 12-20 seconds for contrast to reach renal arteries following iv injection
At this stage, its concentration is maximum in the vascular compartment
This falls rapidly as contrast medium begins to escape into extracellular
compartment and undergoes rapid glomerular filtration and enters the renal
tubules
In first minute of IVU, healthy kidneys (assuming a normal cardiovascular system)
show diffuse enhancement-Nephrogram
During this phase renal size and outline are seen
In roughly first half minute -contrast in the vascular compartment dominates and cortex
is more enhanced than the medulla
This differentiation is sometimes visible in immediate film of IVU series (but regularly
visible on CT performed at this stage)
In second half minute -contrast in the tubules increases and enhancement of kidneys is
more diffuse
At 1 minute: Contrast begins to appear in calyces
After 1 minute:Contrast in the normal calyces begins to drain immediately into the pelvis and
ureters –Pyelogram
On release of compression, there is transient increase in flow down the ureters and release film
offers the best chance of demonstrating the ureters
Normal ureters exhibit peristalsis and on a single film it is uncommon to demonstrate entire
length of both (or even either ) ureters
Preliminary/Control film
Plain film to demonstrate the urinary tract prior to administration of
contrast medium
kVp= 70-80 (low kVp), mAs= 60-70
Supine full length AP view of the abdomen in inspiration
Centering: the vertical central ray is directed to the center of the
cassette
Pelvis should be adjusted so that the anterior superior iliac spines
are equidistant from table top
Lower border of cassette is at level of symphysis pubis
Need of preliminary/control film
To check exposure factors, centering
State of bowel preparation
Obvious pre-existing pathology-urinary tract calculi/calcification
Immediate film/ Nephrogram
AP film of renal areas
exposed 10-14 seconds after
contrast injection (arm to kidney
time)
Renal parenchyma opacified by
contrast medium in the renal tubules
Aim is to see Renal outlines
Measurement of Kidney
Normal size: 9-13cm cephalocaudally,
left is 0.5-1.5 cm larger than right
Normal kidney size should not be more
than 3 times the sum of the height of L1
vertebra and height of L1-L2
intervertebral disc
Significant Discrepancies in size
Right kidney : more than1.5cmlarger than left kidney
Left kidney :more than2cmlarger than right kidney
Measurement of Parenchymal thickness
Averagethickness3-3.5cminpolarregionand2-2.5cmininterpolar
region
Decreaseinparenchymalthicknessseeninpostinflammatoryorstone
relatedscarring
Increaseinparenchymalthicknessisseeninrenalmass
5-min film
AP of Renal areas
Filmtodetermineifexcretionissymmetrical
andforassessingifneed
tomodifytechniquelikeafurtherinjection
ofcontrastmediumifpooropacification
To see Pelvicalycealsystem
Compression technique
Compression band applied around the patient’s abdomen and
balloon positioned midway between the anterior superior iliac
spine -precisely over the ureters as they cross pelvic brim
Compression inhibits ureteric drainage and promotes distension of
pelvicalycealsystem, optimizing their visualization
Before compression
After compression
Contraindications of compression
When 5-min film shows already distended calyces
Recent abdominal surgery
Abdominal Aortic Aneurysms
Acute painful abdomen/ Renal colic
Large abdominal mass
Urinary tract trauma
Presence of Urinary diversion
Presence of Renal transplant
15-min compression film
AP view of renal areas
Adequate distension of pelvicalyceal
system with opaque urine
Compression removed when satisfactory
demonstration of pelvicalyceal system
has been achieved
15-min Release film
Supine AP film
To show whole urinary tract
Post-micturition film
Based on clinical findings and radiological findings on
earlier films, either a full length abdominal film or a
coned view of the bladder with tube angled 15
degree caudad and centered 5cm above the pubic
symphysis
To assess bladder emptying
To demonstrate return of dilated upper tracts with relief of bladder
pressure
Aid diagnosis of VUJ calculi
Diagnosis of bladder tumors
Demonstrate urethral diverticulum
Non-routine projections
Postero-anterior (prone)abdomen
To promote emptying of contrast from the pelvicalycealsystem into
the ureter
Right or left posterior oblique
To show the relationship of the opacities to the kidneys, ureters,
and bladder
Lateral Projection
an alternative to oblique projection in relative position of the
opacities near to or in the kidneys
opacities in the kidneys will overshadow, or be very near the
vertebrae and opacities outside the kidneys are usually shown
anterior to the vertebrae
IVU Modifications
Radiography Modification Purpose
Plain films
Nephrogram
Additional oblique or
tomograms
Thick slice CT
To assist localisationof
intrarenalcalcifications
To improve definition ofrenal
outlines
5min film
15 min compression
film
15 min release film
2
nd
injection of contrast
Series of 1cm thick
tomograms
Additional bladder views
To improve opacificationof PCS
To differentiate between overlying shadows
and filling defects within collecting systems
When bladder poorly filled in release film
When irregular filling defects/calculus in
distal ureter seen oblique films to be taken
Full length post micturitionfilm
Prone full length film
Erect image
Bladder area only
Additional film
Additional film
If upper tracts have already been
imaged to reduce radiation burden
When renal pelvis is dilated
contrast pass slowly ,this can be
accelereted
To imagesmall uretericcalculus by
oblique film
FrusemideIVU Administration of 20
mg of Frusemide iv
after 15 min film with a
further film 15min later
If suspected PUJ
obstruction is being
investigated and there is
no evidence of this on
standard IVU,this
maneuver is performed.
This provokes
hydronephrosisand pain.
Other Modifications
Tailored Urogram
Modifies the urogram to provide the
information needed to include or
exclude the clinical problem
Study is terminated as soon as the
desired information is available
Hypertensive urogram
Minute sequence urogram
Films taken 1,2,3,5 minutes after
injection of contrast media
Drip infusion urography
Contrast is given in 500ml of normal saline
Advantages
-Nephrogrampersists for longer time
-PCS and ureters are visualized for longer time
-No significant increase in contrast reactions
-Administration is easy
Disadvantages
-patient overloaded with more iodine than necessary
-calycealblunting may be produced suggesting abnormal dilatation
-May precipitate CCF in patient with borderline cardiac complaints
-Initial vascular nephrogramis not obtained
Limited Urography
Useful for follow up for earlier
pathology
Limited films taken –KUB, 15 minutes
and post void
High dose urography
Indications
-Renal impairment
-Poor bowel preparation
-Emergency urography
-Vesical fistula
should be very cautious in Diabetes,
Dehydration and in elderly patient
Complications of IVU
Due to contrast
Minor reactions-Nausea,
vomiting, mild rash, headache,
mild dyspnea
Intermediate reactions-Extensive
urticaria, facial edema,
bronchospasm, laryngeal edema,
hypotension
Severe reactions-Circulatory
collapse, pulmonary edema, MI,
cardiac and respiratory arrest
Due to Technique
Upper arm or shoulder pain.
Extravasation of contrast at
injection site
After care
Observation for 6 hours
Watch for late contrast reactions
Prevention of dehydration
In high risk patients –RFT should be done to watch deterioration
Horseshoe Kidney
In utero contact between the metanephric
tissue of the developing kidneys results in
a midline connection (isthmus)
Often visible on the plain film but is better
seen on the nephrogramphase of an IVU
between the lower poles
Flower Vase Appearance
Ectopic Ureter
lower pole moiety displaced inferolaterally
by an upper pole hydronephrosis
occurs due to obstruction of the upper pole
moiety ureter at its orifice associated with
ectopic insertion or ureterocele
Drooping lily appearence
Ureterocele
seen as a non-opacified structure
surrounded by opacified urine in the
bladder
Later, full length film shows
opacification of the distended upper
moiety ureter running down to the
opacified ureterocele
Cobra/Adder Head appearence
Medullary Sponge Kidney
Ectasia(fusiform or cystic) of the
collecting ducts within the renal
pyramids giving Paint brush appearance
Benign incidental finding but there is a
weak association with some tumors
(Wilms),horseshoe kidney and distal
renal tubular acidosis
Hydronephrosis
During the acute episode, features of severe acute obstruction, which include a
delayed, increasingly dense nephrogramand delayed appearance (sometimes
up to 24 h or more) of contrast within the collecting system
When opacificationoccurs, it demonstrates clubbed calyces and a dilated
pelvis
Prior to opacificationof the pelvicalycealsystem, there may be a negative
pyelogram-dilated calyces appearing as radiolucent areas surrounded by the
denser areas of the nephrogram
Crescent/Rim sign
Contrast may be seen with a curvilinear
configuration just peripheral to the calyces
is thought to represent contrast stasis in collecting
ducts displaced around distended calyces
Primary Megaureter
Congenital abnormal musculature of the
distal ureter, leading to focal failure of
peristalsis
The ureter above the abnormal segment
becomes dilated, sometimes massively
Bilateral in 25% cases
Reflux Nephropathy
Small Kidney
Widespread cortical loss (esp.
at upper pole)
Clubbing of calyces
Renal Artery Stenosis
Small and Smooth kidney
Delayed persistent nephrogram
Delayed and dense pyelogram
Ureteral notching
Bladder diverticulum
Focal herniations of urothelium and
submucosa through the weak sites in the
bladder wall
In the early stages, multiple (sometimes
numerous) small protrusions of the
bladder lumen appear between the
trabeculae (sacculations)
As they enlarge above 2 cm, they
become defined as diverticula
Polycystic Kidney Disease
The calyces have a classical
stretched appearance due to the
presence of multiple cysts
Spider leg appearence
MICTURATING CYSTOURETHROGRAPHY(MCUG)/
VOIDING CYSTOURETHROGRAPHY (VCUG)
Radioigraphicexamination of the bladder and urethra while the bladder
is emptying
Filling the bladder with contrast media through urethral catheter /
suprapubicpercutaneous needle
The most commonly used imaging method in the evaluation of the
female urethra and male posterior urethra
INDICATIONS
Children
UTI–done after some weeks of acute stage /under antibiotic coverage
-indicated after the 1
st
occurrence of UTI in boys or girls
Voiding difficulties -dysuria, thin stream, dribbling, frequency, urgency, stress
incontinence
Vesiocuretericreflux(VUR)
Othercongenital anomalies: meningomyelocele, sacral agenesis, rectal anomalies
Baseline study prior to lower urinary tract surgery
Trauma
In renal failure to exclude reflux
Boys with hematuria –demonstration of posterior urethral valve or polyp
Bladder abnormalities
Adults
Main indications
Trauma to bladder and urethra
Posterior Urethral stricture
Suspected vesicaldiverticula
Other indications
UTI
Reflux nephropathy
Prior to renal transplant of one/both kidneys
Follow up of patients with spinal cord injury
CONTRAINDICATIONS
Acute urinary tract infection
Hypersensitivity to contrast media
Fever within the past 24 hours
CONTRAST MEDIA
Water soluble contrast media (150 mg Iodine/ml ) are used, which are diluted with
normal saline in 1: 3 ratio
Equipment
Fluoroscopy unit with spot film device and tilting table
Foley’s catheter
infants:5-7 F feeding tube with side holes
older children: 8F/10F polyethylene/soft rubbercatheter with end
holes
female:the short urethra is difficult to examine
special catheters with two balloons (one for the internal orifice and
one for the external orifice)
PATIENT PREPARATION
History
Allergic to any medications
Allergic to x-ray contrast material
Explain the procedure
Consent
Micturition prior to examination
PRELIMINARY FILM
Coned view of the bladder, using the under couch tube
Supine position
Catheterization
Residual urine drained
PROCEDURE
children upto 2 years: bladder is filled by hand injection
older children :instilled from a bottle elevated one meter above examination table
In newborns, 30-50 cc can be instilled with ease
From about 3 years, girls can hold upto 200-250 cc
The capacity inboys is, 100-150 cc upto 5-6 years of age and 250 cc in older boys
Adequate capacity is reached when the child becomes uncomfortable and begins
voiding around the catheter
The catheter should not be removed until the patient micturates or until no more
contrast medium drips into the bladder
FILMING
In children
Initial filling should be monitored by flouroscopy as catheter may be in
ureter(mimick vesico-ureteric reflux) or vagina
During filling, fluoroscopic screening performed at short intervals to see if
vesiocureteral reflux,diverticuli
The child turned oblique on both sides to ensure that minimal reflux is not
overlooked. If reflux appears, films are taken in the appropriate oblique
projection
Boys should micturate in the LAO position with right hip and knee flexed, or
in RAO position, with left hip and knee flexed so that films are taken of the
entire urethra
The lower ureter is best seen in the anterior oblique position of that side
If the bladder appears normal, one film is taken in the frontal projection at the end of
filling
Voiding starts in infants the moment the catheter is removed
At the end of voiding, a frontal film is made of the entire abdomen including the kidney
region in order to prevent overlooking the vesicouretericreflux which is apparent only on
termination of voiding and may reach the upper collecting system
Inadult male
voiding films taken in both oblique projections
can be modifiedby getting the patient to void against resistance by compression of the
distal part of penis /using penile clamp -Choke cystourethrographywhich enhances
visualization of urethra by the artificial distension
In adult female
The procedure is essentially the same as in girls
In addition to the standard exposures, a double exposed film taken at rest and during
straining demonstrates the degree of bladder descent if any
To demonstrate vesico-vaginal or recto-vesicalfistula: films taken in lateral position
To demonstrate stress incontinence: catheter is left insituuntil the patient is in the erect
position
RADIOGRAPHIC ANATOMY
During active voiding, bladder neck opens widely and becomes funnel shaped in both
male and female patients by means of the internal sphincter mechanism
In male,theverumontanumappears elongated and the proximal bulbar urethra has a less
conical appearance
the membranous urethra remains the narrowest segment between these parts of the
urethra, even though it may dilate up to 6 or 7 mm in diameter during voiding
MCUG may not demonstrate certain abnormalities of the male anterior urethra because the
normal anterior urethra is not fully distended to the degree seen at RGU
Vesicoureteric reflux(VUR)
Grade 1:reflux limited to the ureter
Grade 2:reflux up to the renal pelvis
Grade 3:mild dilatation of ureter and pelvicalyceal system
Grade 4
tortuous ureter with moderate dilatation
blunting of fornices but preserved papillary impressions
Grade 5
tortuous ureter with severe dilatation of ureter and pelvicalyceal system
loss of fornices and papillary impressions
Bladder diverticulum
Posterior urethral valves
-MCUG-the best imaging technique for the diagnosis of posterior urethral valves
-dilatation and elongation of the posterior urethra
-linear radiolucent band corresponding to the valve (only occasionally seen)
-vesicoureteralreflux (VUR):seen in 50% of patients
-bladder trabeculation/diverticula
Vesicovaginal fistula
AFTERCARE
No special after care is necessary
-dysuria
-retention of urine
If reflux is demonstrated in a child who is not receiving antibiotics, they should
be prescribed
COMPLICATIONS
Ascending infection due to catheterization
Due to contrast
Adverse reactions may result from absorption of contrast medium by bladder mucosa
Contrast medium induced cystitis
Due to technique
Urinary tract infection
Catheter trauma causing dysuria, frequency hematuria and urinary retention
Complications of bladder filling-perforation by the catheter or from overdistention
Radiation effect: MCUexposes gonads to radiation
-should be kept minimum
-ensure very short screening periods
-tightly collimated X-ray beam
Autonomic dysreflexia: in paraplegic patients due to spinal cord injury at or above
T6 level
-forceful injection of contrast causes severe headache, sweating and
hypertension with bradycardia due to forceful opening of the bladder neck
-Treat by promptly relieving vesicaldistention or give
diazoxide3-5 mg/kg
EXCRETION MCU (MCU FOLLOWED BY IVU)
use of contrast media accumulated in the urinary bladder during IVU
Advantages
Avoidance of physical and psychic trauma of catheterization
Avoidance of possible infection by urethral catheterization
More physiological ,reliable
Disadvantages
Visualization is not usually adequate
Takes longer time
Vesicoureteric reflux cannot be visualized properly
RETROGRADE URETHROGRAPHY(RGU)
X-ray examination of urethra performed while the contrast is filled up in the urethra from distal
part
considered to be the best initial study for urethral and periurethralimaging in men
a straightforward, readily available, cost-effective examination
INDICATIONS
Pelvic fracture and suspected urethral injury
Stricture
Fistulae
Urethral tears
Congenital abnormalities
Periurethralor prostatic abscess
Foreign body /stone in urethra
Neoplastic lesions of urethra
CONTRAINDICATIONS
Acute UTI
Recent instrumentation
Hypersensitivity to contrast
CONTRAST MEDIUM
HOCM or LOCM 150-300mg iodine/ml, 20 ml
Pre-warming the contrast medium to reduce the incidence of spasm of the external sphincter
Equipment
Tilting radiography table with fluoroscopy unit and spot film device
Foley catheter or penile clamp eg. Knutsson’s
Patient preparation
History
Allergic to any medications
Allergic to x-ray contrast material
Pregnant
Consent
The patient micturates prior to the examination
Preliminary film
Coned supine PA film of bladder base and urethra
Technique
supine
catheter flushed before use
penile clamp applied or the tip of the catheter is inserted so that the balloon lies in the
fossa navicularisand its balloon is inflated with 1-2 ml of water
lubrication not recommended because it may prevent the balloon from remaining in place
for optimal occlusion
supine oblique position
penis placed laterally over the proximal thigh with moderate traction
20–30 mL of contrast material injected under fluoroscopic guidance so that the anterior
urethra is filled
Spasm of the external urethral sphincter occurs which prevents filling of the deep bulbar,
membranous, and prostatic urethra
Examination incomplete until the posterior urethra is filled into bladder base
If external sphincter is in spasm, have patient valsalvaor attempt to void against catheter, then
relax
Slow, gentle pressure needed to overcome resistance
Contrast medium is injected under fluoroscopic control
Films taken in the following positions
-30
o
LAO, with right leg abducted and knee flexed
-Supine PA
-30
o
RAO, with left leg abducted and knee flexed
-Ascending urethrographyshould be followed by MCUG or excretory MCUG to demonstrate
the proximal urethra
-Occassionally,urethralfistula or periurethralabscess is seen only on the voiding examination
-reflux of contrast medium into dilated prostatic ducts is also better seen during micturition
RADIOGRAPHIC ANATOMY
If properly administered, contrast material can be seen to jet through the
bladder neck into the bladder
The verumontanumis seen as an ovoid filling defect in the posterior part of
the prostatic urethra
The distal end of the verumontanummarks the proximal boundary of the
membranous urethra, the region of the external urethral sphincter
The distal boundary of the membranous urethra is the cone of the bulbar
urethra
IDENTIFICATION OF BULBOMEMBRANOUS JUNCTION
important for assessing patients with urethral disease and for planning urologic procedures
When the posterior urethra is optimally opacifiedand the verumontanumvisible, the
bulbomembranousjunction can be identified 1–1.5 cm distal to the inferior margin of the
verumontanum
When the posterior urethra is suboptimallyopacified, the bulbomembranousjunction can
be arbitrarily localized where an imaginary line connecting the inferior margins of the
obturatorforamina intersects the urethra
anterior urethra :end of the membranous urethra to the external urethral meatus
mild angulationof the urethra where the pedulous & bulbar segments join at the penoscrotal
junction
spasm of the constrictor nudae muscle, a deep musculotendinous sling of the bulbocavernous
muscle, may cause anterior or, less frequently, circumferential indentation of the proximal
bulbous urethraand should not be confused with urethral stricture
The membranous urethra should not be confused with stricture
Narrowing elsewhere in the urethra will be clearly defined as separate from the membranous
urethra and representative of a pathologic stricture
If the patient is not positioned sufficiently oblique, the bulbous
urethra will appear foreshortened and will therefore not be
adequately evaluated
Filling of the Cowper ducts should not be misinterpreted as extravasation
Opacificationof the prostatic ducts, Cowper ducts, and periurethralLittre´glandsis
often associated with urethral inflammatory and stricture disease
If the integrity of the urethral mucosal lining is disrupted by increased pressure during
contrast material injection, intravasationof contrast material with opacificationof the
corpora and draining veins may occur
COMPLICATIONS
Due to the contrast medium:rare
Due to the technique:
Acute UTI
Urethral trauma
Intravasationof contrast medium, especially if excessive pressure is
used to overcome a stricture
References
Textbook of Radiology, David Sutton, 7
th
edition
Grainger & Allison’s DIAGNOSTIC RADIOLOGY,7
th
edition
Weir & Abrahams’ Imaging Atlas of Human Anatomy,6
th
edition
Radiopedia