This document provides information on the anatomy, variations, and imaging of the kidneys, ureters, and bladder. It describes the typical location and shape of the kidneys and discusses common anatomical variations. Details are given on renal vasculature and collecting system anatomy. Common congenital anomalies of the kidneys are described. The document also provides imaging protocols for intravenous urography and discusses the goals and findings at different phases of the exam. Contraindications to iodinated contrast are outlined.

1. Dr.Arati Thapa
1st year resident
Department of Radiodiagnosis

2. Usual location- Upper border of 12th thoracic
vertebra and lower border of L3
In an upright position, kidneys descend by 2
or 3 cm in quiet respiration.
Right kidney is slightly lower than left .
Long axis is directed downwards and
laterally – upper pole nearer the median
plane

3. Bean shaped.
Two poles-
Upper- broad due to presence of adrenal
glands
Lower-pointed
Two borders
Lateral-convex
Medial-concave with hilum in middle
Two surfaces-
Anterior- irregular
Posterior- flat

5. 8-16

8. IVP of kidney ureter
bladder

11. Normal size- 9-14 cm
Right kidney is shorter than left by not more
than 1.5cm
As a rule, Kidney length should not be less
than three vertebral body lengths, and no
more than four vertebral body lengths .

14.  The adult kidney may retain some degree of
fetal lobulation. This may involve the entire
kidney or just the middle and lower thirds. It is
frequently bilateral. Fetal lobulation is
distinguished from pathological scarring by
the position of the surface notches: in fetal
lobulation surface notches are between the
calyces, whereas scarring occurs directly over
the calyces.

16. Local bulge or convexity may be seen along
the lateral aspect of left kidney- called
Dromedary hump.
This may be either due to impression of the
spleen or fetal lobulations or both.

30.  If left renal vein passes posterior to abdominal aorta it is
termed as retroaortic left renal vein.
 It has been suggested the variant can sometimes cause
symptoms such as hematuria and abdominal/flank pain.

34.  • The commonest anomaly of development is
duplication of the collecting system, which occurs
in 4% of individuals
 It is characterized by an incomplete fusion of
upper and lower pole moieties resulting in a
variety of complete or incomplete duplications of
the collecting system
 While considered an anatomical variant, duplex
collecting systems may be complicated by
vesicoureteric reflux, obstruction or ureterocele.

35.  Duplex collecting system or duplex kidney
anomalies can be classified into the following
categories depending on the level or lack of
fusion 9-10:
 duplex kidney: two separate pelvicalyceal
systems draining a single renal parenchyma
 duplex collecting system: a duplex kidney
draining into:
 single ureter: i.e. duplex kidney's duplication
pelvicalyceal systems uniting at the pelviureteric
junction (PUJ)
 bifid ureter : two ureters that unite before emptying
into the bladder
 double ureter (complete duplication)

37.  The kidneys may fuse during development
and lead to a horseshoe kidney (1 in 700
births).
 In this condition, the kidney is fused across the
midline in its lower pole.
 The kidney fail to ascend, as IMA would
impede its upward movement. Such kidneys
are more prone to trauma as they lie across the
vertebral column.

39.  One or both kidneys may fail to migrate
cranially, resulting in a persistent pelvic
kidney supplied by a branch of the internal
iliac artery (1 in 1500 births).

41.  In crossed fused ectopia, both kidneys are
located on one side of the midline and are
fused with each other.
 The lower pole of the normally situated kidney
is fused with the upper pole of the ectopic
kidney.

43.  A very rare anomaly called thoracic kidney
(although the diaphragm is usually intact)
occurs when the kidney is found much higher
than its normal position; this may cause an
opacity on a chest radiograph.

52.  Ultrasound -The proximal and distal ureters
may be visible on ultrasound when well
distended. Intestinal gas generally obscures the
midportion unless it is abnormally dilated.

53.  Duplication of part or all of the ureter occurs in
about 4% of subjects. It is the commonest
significant congenital anomaly of the urinary
tract. Duplication is two to three times commoner
in females
 When complete duplication occurs, the ureter
serving the upper renal moiety drains fewer
calyces and is inserted lower into the bladder than
that draining the lower moiety - known as the
Weigert-Meyer law.
 Ureterocoele is a dilation of the intramural
portion of the ureter due to narrowing of its
orifice. This is most common in a duplicated
system.

65.  Diverticulum is the outward bulge of the inner
epithelial lining of the bladder through a defect
in its muscular layer.
 It may be congenital or acquired

67.  Bladder trabeculation happens when the walls
of the bladder thicken, making them harder to
contract.
 It causes retention of urine as it gets difficult to
empty the bladder.

69.  The male urethra runs from the internal
urethral sphincter at the neck of the bladder to
the external urethral orifice at the tip of the
penis.
 In radiological terms ,it may be divided into
posterior and anterior parts. The posterior
urethra comprises the prostatic and
membranous urethra and the anterior part
comprises the bulbous and penile urethra.

70.  Female urethra is 4 cm long
 It extends from the internal urethral sphincter
at the bladder neck through the urogenital
diaphragm to the external urethral meatus
anterior to the vaginal opening. It curves
obliquely downward and anteriorly.

72.  A posterior urethral valve (PUV) is an
abnormal congenital obstructing membrane
that is located within the posterior
male urethra; this valve is the most common
cause of bladder outlet obstruction in male
children

74. 3 zones : peripheral, transition and central
TZ: (5%)- Bilobed zome
CZ(<25%)
PZ ( <70%) Envelope the CZ – majority of the
gland at the apex.

75.  The seminal vesicles are seen as paired,relatively hypoechoic,
symmetric structures cephalad to the base of the prostate
 high signal-intensity fluid on T2WI.
 Their size may vary depending on age and postejaculatory
condition
 The caudal tip of each seminal vesicle joins the corresponding
deferent duct to form the ejaculatory duct.

77. The prostate appears on CT scans as a
homogeneous well-marginated soft tissue
structure, 2-4 cm in length located just beneath the
symphysis pubis immediately anterior to the
rectum

78.  The scrotum covering layers are normally
indistinguishable by sonography and visualized
as single echogenic stripe.
 The testes are homogenous and of medium level
reflectivity
 At birth the testis measures approximately 1.5cm
in length and 1.0cm in width, and before 12 years
of age the testicular volume is 1-2mLs.
 Adult: 3- 5cm in length, 2-4 cm width & 3 cm in
AP.
 12.5-19 g in weight

79.  Compare echotexture
(straddle/spectactle view)

80. • The epididymal head is a pyramid shaped structure lying
superior to the upper pole of the testis. The body courses
along the postero-lateral aspect of the testicle.
• The body and tail are of slightly lower reflectivity when
compared with the testis, whilst the head is of slightly
higher reflectivity or isoechoic .
• The appendix epididymis is not as frequently seen as the
appendix testis .
• The epididymal head measures 10-12mm in diameter &
the body less than 4mm (average 1-2mm) in diameter

82.  thank you

83. Detect and localize a ureteric obstruction
(urolithiasis)
Unknown hematuria
Assess for synchronous upper tract disease in
those with bladder transitional cell carcinoma
(TCC)
 Check for normal function of kidneys
 Check for anatomical variants or congenital anomalies
(e.g. horse-shoe kidney)
 Check the course of the ureters

84. Proven or suspected hypersensitivity to iodine.
Heart disease –cardiac failure /arrhythmias
may be precipitated and in these cases lower
risk with LOCM
Dehydration
Renal impairment
Myelomatosis
Sickle cell anemia
Thyrotoxicosis
Pregnancy
Contraindications

85. Patients taking Metformin
Serum creatinine level above 200 micromol/l

86. Conventionally both the HOCM and LOCM can be used,
however HOCM are rarely used now a days.
Contrast medium

87. Standard Dose:
 LOCM- 300-600mg Iodine eqv/kg body wt.
Adult Dose :50-100ml
Pediatric dose:1ml/kg

88. Bowel preparation
Consider Premedication in patients with prior
history of contrast reaction
Methylprednisolone
32 mg orally 12 hr
and 2 hr prior to
investigation

90. Wide bore IV cannula in place
Emergency drugs and resuscitation equipments
(with skilled personnel) available.
Informed Consent

91.  “Pregnancy” rule should be followed
 Gonad protection!

92. The exact protocol may vary according to the department
rules and need of the patient.
1. Preliminary/scout Film
Administration of CM
2. Nephrographic film
3. 5 minute film
Abdominal compression
4. 10 minute renal and upper urinary tract film
5. 15 minute release film of ureter and bladder
6. Bladder image
7. Post micturition image
Modifications can be used in any steps if the image is not
satisfactory.

93. Done to check exposure
factors, centering, bowel
preparation and obvious
pathology, particularly
UT calcification.
Technical considerations:
Positioning, Proper collimation,
Proper KVP and amperage/exposure
time

94. Location of calcifications in the abdomen with
respect to the urinary tract should be made prior
to the injection of contrast material, which can
obscure a calcification.

95. Role of Oblique radiographs

96.  AP view of renal areas.
 This film is exposed 10-14 seconds after contrast
injection (arm to kidney time)
 Aim: to show nephrogram

98. What to see in Nephrographic phase?
• Temporal symmetry of
nephrographic development.
• Entire renal contour- Entire contour
should be assessed , inability to
visualize a portion of contour
requires explanation
• Position and axis
• Size of both kidneys.

99.  Normal size: 10-15
cm cephalocaudal,
left is 1.5 cm longer
than right.
 Not more than 3
times the sum of the
height of L1 vertebra
and height of L1-L2
intervertebral disc.

100. Right kidney is more than 1.5cm
larger than left kidney
Left kidney is more than 2cm larger
than right kidney

101. AP view of renal areas
Initial assessment o pathology.

102. Before compression After compression

103. 
Average thickness 3-3.5cm in polar region and
2-2.5cm in interpolar region

Decreased and increased
parenchymal thickness to be assessed
Interpapillary line

104.  Abdominal aortic aneurysm
 Recent abdominal surgery
 If patients abdomen is tender
 Acute painful abdomen/ renal colic
 Large abdominal mass
 Evidence of obstruction in 5 minute film
 Suspected urinary tract trauma
 Presence of urinary diversion or renal transplant

106.  Supine AP film
 This film is taken to
show ureters.

107. • Diameter exceeding 8 mm; asymmetry of ureteral
caliber more significant finding.
• Deviation of ureter.
What to see in ureter:

112. 1)Postero-anterior (prone) abdomen
Projection is to promote emptying of contrast from the
pelvicalyceal system into the ureter.
2)Right or left posterior oblique- this is to show the
relationship of the opacities to the kidneys,
ureters and bladder.
3)Lateral Projection may be used as an alternative
to oblique projection in relative position of
the opacities near to or in the kidneys.

113. Position: Pt. lies prone after doing 15 min full
film and after 4-5 min. of lying prone (so that
lower ureter is dependent part) full film is
taken.
To investigate pelviureteric and ureteric
obstruction as the heavy contrast loaded urine
will more readily gravitate to the site of the
obstruction.
To displace the overlying bowel gas towards
periphery.

114. Can be Considerable upto 24 hours.
In case of :
 Significant acute obstruction when early
nephrogram is seen but collecting system is
not seen.
 Long standing hydronephrosis
 Congenital lesions like non-visualized upper
calyceal system with ectopic or obstructed
ureter.

115. As many films are taken, it is necessary to
perform minimum no. of additional films.
Time interval is generally doubled (and taken
as 0.5, 1, 2, 4, 16, 24 hours
If no opacification of an acutely obstructed
kidney at 30 min it is usually unhelpful to
perform the next film before around 4 h after
contrast injection.
A further manoeuvre to minimise radiation
dose in patients with a strong clinical
suspicion of ureteric colic is to omit all films
after contrast until a full length 15 min film is
performed.

116. CHILDREN
 Films at 2 min (supine)
and 7 min (prone) is
taken after contrast
administration.
 Or a 2 min (renal area) ,
5 min (renal area),and 15
min full length
abdominal film.
 Abdominal compression
not used.
 To improve visualization
of left kidney child can
be given a carbonated
beverage.
 The right kidney can be
well seen through the
liver in a 15-20 degree
caudal tilted view.
NEONATES
 Excretion of contrast
medium is delayed and
prolonged.
 The concentration of
contrast medium is
relatively poor.
 Optimum visualization of
upper UT may not occur
until 1-3 hour.
 If initial 2 min and 5 min
film show little
opacification, further film at
1, 2 and 3 hour may provide
more information than
multiple films in 1st hour.

117. Suspicious shadows in renal areas:
Lateral film of renal area is taken.
Inspiratory and expiratory film of renal area is
taken to demonstrate the relationship of
opacities and filling defects of renal tract.

118. Useful when intermittent obstruction is
suspected but cannot be confirmed by standard
urogram.
I.V. frusemide is used to induce diuresis.
The dose of Lasix/Frusemide is 0.3-1mg/kg in
adults and 0.5mg/kg in child.
The film is taken 5-10 mins after adminstering
the diuretic.

119.  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.

120. Also called as minute sequence urogram.
Films are taken 1,2,3,5 minutes after injection of
contrast media.
For Renal artery stenosis-
 decreased renal size.
 delayed appearance of contrast material (decreased glomerular
filtration)
 increased density of contrast material (increased water
reabsorption)
 delayed washout of contrast material (prolonged urine transit
time)
 lack of distension of collecting system
 global attenuation of contrast density; urogram may be normal
with adequate collateral circulation
 notching of proximal ureter (enlargement of collateral vessels)

121.  Small and Smooth kidney
 Delayed nephrogram
 Delayed and dense pyelogram.
 Ureteral notching

122. Disadvantages:
 Overload the patient
with more iodine than
necessary.
 Calyceal blunting may
be produced suggesting
abnormal dilatation.
 May precipitate CCF in
patient with borderline
cardiac complaints.
 Initial vascular
nephrogram is not
obtained.
Advantages
• Nephrogram persists for longer
time.
• Enhanced diuresis from the
additional contrast media and water
volume will distend the collecting
system and ureters more clearly.
• Collecting system is visualized for
longer time.
• No significant increase in contrast
reactions.
• Administration is easy.
Contrast is given in 500ml of normal saline.

123.  Useful for follow up for earlier pathology
 Limited films are taken - KUB , 15mins and post void.

124.  Haemodynamically unstable patient destined for
emergency laparotomy a single shot IVU (full
length film 15 min after contrast injection)
may be considered.

125. 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, pul edema,
MI, coma, cardiac and respiratory arrest
Due to Technique
Upper arm or shoulder pain.
Extravasation of contrast at injection site

126.  Observation for 6 hrs
 Watch for late contrast reactions
 Prevention of dehydration
 In high risk patients – RFT should be done to watch
deterioration.

127. PROTOCOL
 Oral water load 0.5-1 l,30-60 min before
 Patient supine.
 CT kub
 LOCM,300 mg I/ml,100 ml bolus IV
 1mm slice from diaphragm to lower pole of kidney ,100 sec
following bolus injection for nephrographic phase/parenchymal
phase.
 Delayed scan from the upper pole of kidney to bladder base ,20 min
after injection for collecting system and ureter.SPLIT BOLUS
TECHNIQUE
▪ CT UROGRAM
SPLIT BOLUS TECHNIQUE
50 ML OVER 10-15 MIN BEFORE SCAN, 50 ML AT THE TIME OF SCAN
BOTH NEPHROGRAPHIC AND PYELOGRAPHIC PHASE CAN BE SHOWN AT SAME ACQUISITION WITH LOWERING THE
RADIATION DOSE

128. Phases of study:
a. Unenhanced
b. Corticomedullary
c. Nephrographic
d. excretory

132. MAINLY DIVIDED INTO TWO CATEGORIES
1. STATIC MR :-T2 BASED SEQUENCE ,INDEPENDENT OF RENAL
EXCRETORY PROPERTY AS IT USES URIE AS CONTRAST
AGENT,MAINLY FOR DILATED OR OBSTRUCTED COLLECTING
SYSTEM
2. .EXCRETORY MR UROGRAPHY :- T1 BASED POST GADOLINIUM ,
CAN BE DONE WITH NORMAL COLLECTING SYSTEM, USUALLY
POST DIURETIC.GOOD FOR FUNCTION AND MORPHOLOGY

133. ADVANTAGE OF MR UROGRAPHY OVER CT UROGRAPHY
1.ELIMINATION OF IONIZING RADIATION.
2.NON IONIC CONTRAST
3.CONTRAST RESOLUTION
4.NON CONTRAST IMAGING
ADVANTAGES OF CT UROGRAPHY OVER MR UROGRAPHY
1.CLAUSTRO
2.CT:15 MIN, MR:45 MIN
3.SPATIAL RESOLUTION
4.CALCIFICATION NOT SEEN
5.COST
6.UNCOOPERATIVE PATIENTS

135. Indications of IVU
Contrsindications of IVU.
IVU modification in renal artery stenosis
IVU modification in puj obstruction.
Types of contrast and amount in IVU
CT protocol for IVU.