Intravenous urography

RamanGhimire3 2,249 views 102 slides Aug 14, 2021
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About This Presentation

INTRAVENOUS UROGRAPHY (IVU) ,MICTURATING CYSTOURETHROGRAPHY (MCU), RETROGRADE URETHROGRAPHY (RGU)


Slide Content

INTRAVENOUS UROGRAPHY (IVU)
MICTURATING CYSTOURETHROGRAPHY (MCU)
RETROGRADE URETHROGRAPHY (RGU)
DR. CHHABI KHADKA
RESIDENT
RADIODIAGNOSISAND IMAGING, NAMS,BIRHOSPITAL

Intravenous Urography(IVU)
imagingoftheurinarytractfollowingtheintroductionofawater-
solubleintravenouscontrastmedium
structural&functionalevaluationofurinarytract
contrastexcretionbykidneys,renderingtheurineopaquetox-rays
andallowingvisualizationoftherenalparenchyma,calyces,renal
pelvis,uretersandbladder

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

Relative
Asthma/History of significant allergy
Beta blockers
Chronic renal insufficiency
Cardiac disease –Cardiac failure /arrhythmias
Diabetes
Dehydration
Multiple Myeloma
Metformin therapy
Sickle cell anemia
Thyrotoxicosis
Pregnancy

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

Contrast agents:
Iopramide(ultravist): non ionic LOCM,300,370mg Iodine/ml
Iohexol(omnipaque):non ionic LOCM, 300,350 mg Iodine/ml
Standard Dose:
Adult Dose : 50-100 ml
Pediatric dose: 1 ml/kg

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

Thank You