renal radiology revision notes for neet pg preparation based on previous year questions

1. Renal radiology

2. Assessment of GFR
• Inulin  gold standard & most accurate
• Creatinine clearance  Mc used
• Chromium labelled EDTA
• Tc99m DTPA cost effective & accurate

3. IVP

4. IVP/intravenous urography/excretory
urography
• Sequence
• Plain KUB film → Nephrographic phase and a 5 minutes after injection of
contrast →full-length 15 minutes film →30/45 minutes prone full length film
and lastly the post-void film.

6. IVP
indications Relative
• Hematuria
• Renal colic
• Recurrent UTI
• Suspected urinary tract pathology
• Multiple myeloma
• Liver failure with renal failure
• Pregnancy
• Previous history of reaction to contrast
• Severally dehydrated patient

7. Modifications of IVP
Rapid sequence IVU: • Done in patients with suspected renovascular
hypertension.
• Films taken at 1, 2 and 4 minutes after injection of
contrast medium in addition to the routine filming
sequence
Infusion urography: • Done in patients with compromised renal function.
• 40–50 grams of iodine (as against 16 grams in usual
procedure) is injected into 200–500 cc of glucose
and given as infusion.
Diuretic urography:​ • Done in patients with PUJ obstruction. A patient is
not dehydrated prior to procedure. IV frusemide is
injected immediately following contrast, which
causes copious contrast secretion, thus dilating the
renal pelvis to greater extent and demonstrating
the pathology nicely.

8. IVU / IVP
Nephrogram  to
assess kidney
Pyelogram to assess
pelvicalyceal phase

9. Nephrogram

10. Dense nephrogram
Increasingly dense nephrogram Immediate dense nephrogram
• a/c obstruction
• a/c hypotension
• Renal vein thrombosis
• a/c tubular necrosis
• a/c obstruction
• Hypotension / shock
• Renal vein thrombosis
• a/c tubular necrosis
Dense nephrogram can also be produced by dehydrating the patient

11. Methods for obtaining dense nephrogram
• Increase concentration of nephrogram
• Rapid bolus injection  preferred method
• Dehydrating the patient abdominal ureteric coimpression devices /
technique

12. Striated nephrogram
• Linear bands of contrast extending from medulla of kidney towards
cortex
u/l striated nephrogram b/l striated nephrogram
• a/c ureteric obstruction
• a/c pyelonephritis
• a/c renal vein thrombosis
• a/c following renal contusion
• a/c radiation therapy
• ARPKD
• a/c pyelonephritis (if b/l)
• Hypotension
• a/c tubular necrosis

13. Retrograde pyelography / pyeloureterography
• Radiography of ureter & renal collecting system
Indications C/I
• Demonstration of site length & lower
limit of obstructive lesion
• Demonstration of pelvicalyceal system
after an unsatisfactory IVP
• UTI
IOC for anterior urethral valve

14. Voiding cystourethrography (VCUG)
• is of value in the diagnosis of vesicoureteral reflux and bladder neck
and urethral obstructions.
• Patients with obstruction at or below the level of the bladder exhibit
thickening, trabeculation, and diverticula of the bladder wall.
Postvoiding films reveal residual urine.
• If these radiographic studies fail to provide adequate information for
diagnosis, endoscopic visualization by the urologist often permits
precise identification of lesions involving the urethra, prostate,
bladder, and ureteral orifices.

15. Voiding cystourethrography
• Voiding cystourethrography is the best
radiographic study available to establish the
diagnosis of posterior urethral valves.
• The presence of large amounts of residual urine is
apparent on initial catheterization done in
conjunction with radiographic studies, and an
uncontaminated urine specimen should be
obtained via the catheter and sent for culture.
The cystogram may show vesicoureteral reflux
and the severe trabeculations of long-standing
obstruction, and the voiding cystourethrogram
often demonstrates elongation and dilatation of
the posterior urethra, with a prominent bladder
neck.

16. Voiding cystourethrography
• IOC To assess vesicoureteric reflex
• Posterior urethral valve
• IOC of Visualise posterior urethra

18. Renal scintigraphy

20. Static/ anatomical /morphological Dynamic/functional
Type of scan DMSA DTPA or MAG3
Properties of substance used • Filtered & reabsorbed in PCT
• Getting concentrated in cortes
to detect scars
• DTPA  most preffered for GFR
(neither reabsorbed r secreted )
• MAG3  renal perfusion is best
studied (BEST STUDY FOR RENAL
FUNCTION as it is filtered &
secreted )
Function • Cortical function
• Corticomedullary differentiation
• Functional mass
• Scarring of VUR
• Detect horse shoe kidney
solitary or ectopic kidney

21. Renal radionuclide imaging
• Dynamic renal scintigraphy  functional imaging Static renal scintigraphy
Tc99 DTPA GFR estimation Tc99m DMSA
• To assess cortical function / corticomedullary
differentiation/ functional mass / scarring of VUR
Tc99 MAG 3  best for dynamic renal scintigraphy
I123 –OIH  effective renal plasma flow

22. Dynamic renal scintigraphy
Tc99m DTPA GFR estimation Tc99m MAG3
• DTPA  neither reabsorbed / secreted
• Used to measure GFR
• Demonstration of VUR
• Differentiate obstruction from stasis by diuretic
DTPA scan
• To assess transplanted kidney
• MAG3 is secreted as well as filtered
• Best study for renal function
• Glomerular + tubular function
Captopril DTPA is used for detecting reno vascular HTN

23. • For detecting renovascular HTn  captopril DTPA screening is used
Captopril DTPA Screening investigation in renovascular
hypertension
Tc99m DTPA Cleared only via glomeruli with no
tubular excretion  direct measurement
of GFR
Tc99m MAG3 Excreted via both glomerular filtration &
tubular excretion
Tc99m DMSA • Assess renal imaging to evaluate renal
structure & morphology
• Retained in cortex for longer duration

24. Functional renogram

25. In case of obstruction
Exretion doesnot occur if
Lasix is given
In case of stasis excretion
occurs following injection
of furosemide

26. Central echogenic structure
represents vascular elements
calyces & renal sinus fat
Renal pyramids are hypoechoic

27. nephrocalcinosis
Medullary calcinosis (95%) Cortical calcinosis
• hyperparathyroidism,
• medullary sponge kidney,
• renal tubular acidosis,
• hypervitaminosis D
• primary hyperoxaluria
• acute cortical necrosis,
• Chronic glomerulonephritis and
• primary hyperoxaluria
• Alport syndrome
• Graft rejection
• Stippled calcification in medulla on radiogram • Stippled calcification in cortex on radiogram
• On ultrasound, increased echogenicity • On ultrasound, increased echogenicity

28. Cortical nephrocalcinosis

29. Fine stippled calcification in nephrocalcinosis

30. Renal cyst

31. Bosniak classification of cyst

33. ADPKD ARPKD
b/l diffuse cyst in renal parenchyma Cysts perpencdicular to renal capsule
Swiss cheese pattern on nephrogram Striated nephrogram
Spider leg pyelogram

34. Spiderleg pyelogram in ADPKD

35. AD Polycystic kidney disease (gene on chr 4 &
16 )
• Autosomal dominant
• a/w
• cysts in pancreas lung testis / berry aneurysm
• Colonic polyps
• Co arctation of aorta
• Valvular heart disease
• Autosomal recessive
• Congenital hepatic & periportal fibrosis
• IVP  spider leg appearance

36. ADPKD

37. USG finding in ARPKD
• Antenatal USG
• Associated oligohydramnios
• Cysts
• Unlike ADPKD rarely exceed 2cm

38. Striated nephrohrogram
• ARPKD
• a/c pyelonephritis d/t ischemia

39. Multicystic dysplastic
kidney
• Nonvisualisation of kidney on IVP
 multicystic dysplastic kidney
• Multicystic non communicating
cysts
• absence of normal pelvicalyceal
system

40. b/l multicystic dysplastic kidney + pulmonary
hypoplasia  potter syndrome

41. Multiple cysts of various sizes  soap bublle
appearance

42. Paint brush appearance of medullary sponge
kidney

43. Medullary sponge kidney
• Paint brush appearance on IVP
• Medullary sponge kidney
• Bunch of flowers

45. Horse shoe kidney

46. Diagnosis of horse shoe kidney
• IVP
• Low lying kidney
• Hand joining sign
• Flower vase sign

47. Flower vase sign in horse shoe kidney
Medially rotated calyces

48. Hand holding calyces in horse shoe kidney
d/t shifting of parenchyma
medially

49. Renal papillary necrosis

51. Papillary necrosis
• DM  commonest cause
• Analgesic nephropathy
• Sickle cell anemia
• c/c alcoholism
• Urinary tract obstruction
• a/c pyelonephritis

55. • Ball-on-tee appearance: Contrast material filling central excavations in the
papilla of the interpolar region gives ball-on-tee appearance.
• Lobster claw sign: Excavation extending from the caliceal fornices produces
the lobster claw deformity.
• Signet ring sign: The necrotic papillary tip may remain within the excavated
calyx, producing the signet ring sign when the calyx is filled with contrast
material.
• Club shaped saccular calyx: Due to sloughed papilla

56. Egg in cup
appearance
Golf ball on a
tee sign
Lobster
claw sign Ring sign

57. Golf ball on tee

59. Ureters

60. Rim sign in c/c hydronephrosis
c/c hydronephrosis (rim
sign)
Rim/quiescent / meciscus sign

61. • Drooping lilly sign
• Duplex kidney with nonfunctional upper moiety
• Also seen in RCC

62. Drooping lilly sign  duplex ureter

64. Fish hook ureter
• S shaped ureter
• Right sided fish hook ureter  right
ureter hooks behind IVC (RETROCAVAL
URETER)
• Developmental anomaly of IVC
• Persistent right posterior cardinal V
therefore ends passing infront of ureter

65. Retrocaval ureter

67. b/l fish hook appearance describe course of
distal ureter in patients with significant BPH

68. Maiden waist deformity in retroperitoneal
fibrosis

69. Maiden waist deformity

70. Goblet sign
• Champagne glass sign
• irregular ureteric narrowing with
proximal shouldering termed the
goblet sign
• Focally dilated intraluminal mass
• Causes of goblet cells
• TCC of ureter
• Metastatic ds in to ureter
• Endometriosis involving ureter

72. Goblet sign in transitional cell carcinoma

73. Weigert mayer
rule
• Superior moiety inserts
inferomedially on bladder(SIMO)
• Prone for obstruction 
hydronephrosis
Superior
pole
• Lower moiety inserts
superolaterally
• More prone for obstruction
Lower
pole

74. Urinary tract tuberculosis

75. Renal tuberculosis
Renal tuberculosis
IOC  CECT
Earliest investigation is IVP
Kidney Ureter Bladder
• Moth eaten calyces (earliest)
• Putty kidney (slow volume
shrunken)
• Cork screw
• Golf hole ureter (cystoscopic)
• Kirr kink ureter
• Thimble bladder

76. Moth eaten appearance

77. Renal tuberculosis
• Earliest  ill defined calyx
• IVP  IOC

78. Putty kidney  tuberculosis

82. Beaded or cork screw ureter

83. Phantom
calyces

85. Golf hole ureteric opeing on cystoscopy in TB

86. Thimble like bladder
• Chronic tuberculous cystitis
healing is through fibrous
contracture

87. Cobra head sign / adder head appearance
• Bulbous dilation of distal end of
ureter with a surrounding
radioluscent halo
• Intravesical ureterocele

88. Cobra head appearance

89. Adder head appearance in ureterocele

90. Bladder

91. Tear drop / pear shaped bladder
• d/t Extrinsic compression  pear shaped
• Pelvic abscess
• Pelvic lipomatosis
• Pelvic haematoma
• Symmetric pelvic lymphadenopathy
• Intraperitoneal bladder rupture

92. Fetal head calcification in bilharziasis

93. Christmas tree bladder in neurogenic bladder
• Pine cone bladder
• In severe neurogenic bladder with
increased sphincter tone

94. Bladder injuries
Intraperitoneal Extraperitoneal
Contrast extravsation in b/w bowel loops & peritoneal
folds
Contrast extravsation in perineum  molar tooth sign

95. Molar tooth sign

96. In extraperitoneal extravsation of bladder

97. Molar tooth sign

98. Renal artery hypertension

99. Renovascular hypertension
• Atherosclerotic disease
• Fibromuscular dysplasia
On IVP MR angiography Spiral CT scan
• Delayed / absent nephrogram
(delayed wash out)
• Normal / atrophic kidney
• With out caliceal deformity
• Ureteral kinking
• Rim nephrogram
• IOC • One of the most
sensitive &
specific screening
test (after
angiography)

100. Renal artery stenosis
• Significant if diameter is >50 % is decreased
• Causes
• Atherosclerosis
• In elderly
• Fibromuscular dysplasia
• Children
• String of beads on angiography
• b/l
• Taksyasu arteritis
• RTx for pheochromocytoma
• Thrombo embolism
• IOC
• MRA
• ACE inhibitors are C/I in RAS

101. String of beads appearance in fibromuscular
dysplasia

102. Renal artery stenosis
• Significant renal A stenosis
• presence of collaterals
Hemodynamically significant ranal artery
stenosis
• Presence of collateral vessels  most
important sign
• Elevated renin in ipsilateral vein
• Decrease in renal size
• Greater than 70 % stenosis with post stenotic
dilation
• Transstenotic pressure gradient > 40 mmHg

103. Chronic renal failure

104. Rugger jersey spine is seen in c/c renal failure
(hyperparathyroidism)

107. Sandich
spine in
osteopetrosi
s

108. Ureteric stone

109. Calcium oxalate /Spiculated/lamellated/mulberry
stones)
75%
Struvite (magnesium ammonium phosphate/
Laminated/ proteus induced/staghorn)
15%
Calcium phosphate (laminated) 5 %
Uric acid 5 %
5. Cystine; xanthine; orotic acid; matrix
Mucoprotein or mucopolysacchride)
rare

110. Staghorn calculi

111. Ureteric & renal stone
• In lateral view
• GB stone lies anterior to spine
• Ureteric stone LIES OVER THE SPINE
• Plain Xray KUB  1st investigation in ureteric stone

112. Investigations of urolithiasis
• CT better than USG for ureteric calculi
• NCCT is better than CECT
• Dual energy CT  characterise type of stone

113. Renal & ureteric stones
• Non contrast spiral
CT IOC

114. Ureteric stones
• Radiolucent renal calculi are:
• Uric acid stones
• Xanthine stones
• indinavir associated stones
• Cysteine stones
• orotic acidurea
• Matrix (mucoprotein) stones

115. Posterior urethral valve
• remnant of the Wolffian duct and consists
of a raised mucosal fold which courses
obliquely from the verumontanum to the
inferior aspect of the prostatic urethra
• VCUG/MCU is the IOC in diagnosis of
posterior urethral valve
• In micturition phase in lateral or oblique views
• Findings
• Dilation & elongation of posterior urethra
• Radioluscent band corresponding to posterior
urethral valve
• Vesicoureteric reflex
MCU USG
Dilated & elongated
posterior urethra
Key hole appearance

116. Posterior urethral valve
posterior urethra is both
dilated and
lengthened

117. Keyhole sign in USG of posterior urethral
valve
• Appearance of
proximal urethra

118. Testicular tosrsion
• Doppler is the IOC for evaluation of a/c scrotal pain & scrotal pain

119. DJ stent