COMPREHENSIVE IMAGE SUPPORTED ASSESSMENT OF VARIOUS LESIONS OF KUB.

1. KUB:
Benign neoplasms
Dr arif khan s

2. INTRODUCTION
URINARY SYSTEM
 KIDNEYS
 URETER
 BLADDER

3. RENAL NEOPLASM
 Adult
 Paediatric
WHO classification categorises neoplasms on basis of cell of origin and
histopathology.
Most renal tumors arise from the parenchyma, refered to as renal cell tumors
Small number from mesenchyme and collecting system.

4. WHO 2006 (hiedelberg classfication)
Renal cell tumours
Malignant
 • Clear cell renal cell carcinoma
 • Multilocular clear cell renal cell carcinoma
 • Papillary renal cell carcinoma
 • Chromophobe renal cell carcinoma
 • Carcinoma of the collecting ducts of
Bellini
 • Renal medullary carcinoma
 • Xp11 translocation carcinomas
 • Carcinoma associated with neuroblastoma
 • Mucinous tubular and spindle cell
carcinoma
 • Renal cell carcinoma unclassified
Benign
 Papillary adenoma
 Oncocytoma

5. Mesenchymal tumors classification
(W.H.O ………contd)
Metanephric tumors
 • Metanephric adenoma
 • Metanephric adenofibroma
 • Metanephric stromal tumors
Mixed mesenchymal and epithelial tumors
 • Cystic nephroma
 • Mixed epithelial and stromal tumor
 • Synovial sarcoma
Nephroblastic tumors
 • Nephrogenic rests
 • Nephroblastoma
 • Cystic partially differentiated nephroblastoma
Neuroendocrine tumors
 • Carcinoid
 • Neuroendocrine carcinoma
 • Primitive neuroectodermal tumor
 • Neuroblastoma
 • Pheochromocytoma
Other tumors
 • Mesenchymal tumors
 • Hematopoietic and lymphoid tumors
 • Germ cell tumors
 • Metastatic tumors

6. Balls v/s beans concept
 By Harman and ros
BALL TYPE
 Most by expansion appears as exophytic balls from the poles
 Eg: cysts, renal cell carcinomas, angiomyolipoma, metastasis,
oncocytoma
 These masses are shaped similarly to spheres or balls and they
displace and compress, rather that invade normal structure
BEAN TYPE
 grow along the latticework of normal renal parenchyma
 Infiltrating lesions swell the area of involved parenchyma,
 do not deform the shape. The kidney retains the ‘bean’ shape.
 These are difficult to detect radiologically since little mass effect
 is associated.
Eg;
 transitional cell carcinoma, squamous cell, lymphoma,
renal medullary carcinoma

7. Imaging modalities
 IVU
 Excretory urography lacks specificity for accurately characterizing a
lesion.
 Expansile masses cause contour abnormalities, calcyeal splaying,
stretching and draping.
 Infiltrating renal mass produce little parenchymal mass effect and
maybe seen as a filling defect in the collecting system.

8. Ultrasound
 Ultrasound is very useful for detection of renal masses and
characterizing them as solid or cystic.
 Ultrasound may also be useful when CT pseudoenhancement
is noted, leading to a simple renal cyst being mischaracterized as
solid mass.
 Color Doppler sonography can evaluate renal vein and IVC for
presence of thrombus
 The vascular flow within a renal mass, identified by color and
power Doppler is strongly associated with clear cell carcinoma.
 Peripheral or mixed peripheral and penetrating patterns are
seen.

9. CT
 CT is accurate in detection, characterization and staging of renal masses.
 MDCT allows fast, multiphase and high resolution imaging
 For characterization of a renal mass, the examination is to performed before
and after administration of IV contrast
 the different phases of renal enhancement
 arterial (15-20sec delay)
 corticomedullary (35-80 sec),
 nephrographic (85-180 sec) and
 excretory (3 min or more) need to be evaluated.
 The nephrographic phase is ideal for detection of masses as there is maximal andhomogenous
parenchymal enhancement

10.  In corticomedullary phase, small renal masses may be indistinguishable
from renal medulla.
 excretory phase, masses may be same attenuation as the parenchyma
which has de-enhanced.
 Cortico-medullary phase may help in characterizing pseudo-tumors such as
hypertrophy of column of Bertin
 Careful attention is to be given to enhancement that is identified as
unequivocal and not due to pseudoenhancement which is elevated HU
measurement of cyst due to image reconstruction algorithm
 It may be useful to adopt gallbladder or a simple cyst (when present) as
internal reference standard for Hounsfield unit measurement
 An increase in attenuation of 10 HU or more in a lesion measuring at least
2 cm in diameter indicates enhancement

11.  As enhancement is transient, washout of contrast is also useful.
 If an area of enhancement decreases subjectively or quantitatively (at least 10
HU), neoplasm is suspected. This is called “de enhancement”.
 CT urography is beginning to replace IVU as the imaging examination of choice to
detect upper urinary tract tumors.

12. MRI
 especially useful in patients in whom iodinated contrast is contraindicated.
PROTOCOL
 Coronal HASTE for planning ,
 axial T2-weighted gradient and spin echo with fat suppression,
 axial dual echo in phase and opposed phase gradient echo T1 images, and
 3D fat suppressed GRE T1 images before and after iv contrast
 followed by a coronal 3D fast gradient echo sequence with fat suppression after the
dynamic series to display renal venous anatomy and IVC,
 MRimaging is valuable for distinct renal lesions.
 On MR imaging, hemorrhagic cysts have high signal on T1WI.
 A homogeneous hyperintense lesion on T2 with a thin wall and no enhancement is a renal
simple cyst.

13.  All 3 phases of renal excretion are obtained after contrast and subtraction
images may be obtained to determine, percentage of enhancement
 In and opposed phase images help in detecting intratumoral fat.
 MR urogram is indicated in patients with suspected collecting system disease

14. Oncocytoma
 solid non-fat containing renal mass,
 Arising from proximal tubule with many characteristics of RCCs
 Most oncocytomas are asymptomatic (80%), but few may present with
hematuria pain or mass
 The peak age of incidence is in the seventh decade with a male pre-
ponderance.
IMAGING
 as well demarcated, unencapsulated, fairly homogeneous renal cortical
tumors.
 Bilateral multiple oncocytomas are seen in hereditary syndromes of renal
oncocytosis

15.  USG may show a central stellate scar within a solid
hematogenous mass.
 Generally tend be large well demarcated tumours at
presentation.
Non contrast
 if less than 3 cm - homogenous attenuation
 if more than 3 cm - heterogenous attenuation
 perinephric fat-stranding may be present due to
oedema
 calcification may be present

16. Post contrast
 small tumours may enhance homogeneously, but
usually enhancement is heterogenous and the
mass is larger
 central stellate non-enhancing scar is seen in
approximately a third of cases 4
 renal vein thrombosis may be present, but
tumour thrombus is absent.
 Post contrast: Cart wheel Enhancement
homogenously enhancing
 The presence of a central scar, absence of
calcification or necrosis and haemorrhage
suggests the diagnosis

17.  Surgery is usually performed for these and HPE is
indicated to confirm both.
 MRI: T1W – Hypo to iso intense ; T2W
hyperintense,
 The central scar, if present is hypointense on T2
 Post contrast show heterogenous enhancement

18. Renal Adenomas
 Papillary adenomas are the most common renal epithelial
neoplasm
 According to autopsy series, approximately 40 percent
of patients above the age of 70 harbor renal adenoma.
 They are indistinguishable from RCCs.
 papillary adenomas measure 5 mm or less
 peak age in 5th-6th decades
 a welldefined, unencapsulated, solitary solid mass.
 Metanephric adenomas display hypovascularity and
delayed, minimal enhancement

19. Metanephric adenoma
 asymptomatic in many patients few with pain and hematuria.
IMAGING
 difficult to differentiate from other renal tumours such as renal cell
carcinomas
 typically appears as a well-defined expansile hypoechoic or hyperechoic. ,
unencapsulated, solitary solid mass on sonography.
 appears as a hyper attenuating mass on unenhanced CT;
 large tumors appear as heterogeneous, hypovascular masses with frequent foci
of hemorrhage and necrosis.
 Calcification is seen in 20% of cases
 MRI: T1 hypointense , T2 hyper intense ;few hypointense

21. ANGIOMYOLIPOMA
 These benign lesions are mesenchymal neoplasms
 A type of hamartomas
 Represents Excess growth of fat , smooth muscle and thick walled
blood vessels
 Amount of Each component is variable
 Histologically proliferation of perivascular Epitheliod cells
(PEComas)
 Tuberous sclerosis is the most commonly associated syndrome.
 Multiple and bilateral angiomyolipomas should suggest the
diagnosis of TS
 Other assosciations include NF-1 , ADPKD, vHL

22. IMAGING
 large, heterogeneous masses with varying amount of macroscopic fat
 intralesional aneurysms and hypervascular soft tissues seen.
 Angiomyolipomas are composed of thick walled inelastic blood vessels,
 Risk of intratumoral and perinephric hemorrhage is higher in lesion > 4 cm diameter

23.  USG:
 hyperechoic lesions on ultrasound, located in the cortex
and with posterior acoustic shadowing
 in tuberous sclerosis, they may be so numerous that the
entire kidney is affected, appearing echogenic with loss of
normal cortico-medullary differentiation.
 ontrast-enhanced ultrasound tend to enhance peripherally
with decreased central enhancement, compared with
normal cortex

24.  CT
 Most lesions involve the cortex and demonstrate
macroscopic fat (less than -20 HU)
MRI
 excellent at evaluating fat containing lesions
 Appear hyper in T1 wt images ,
 In RCC also mascroscopic fat is seen. But lack of
uniformity and capsular breach all be there
 macroscopic fat in RCC almost always occurs in
the presence of ossification/calcification,
 absence of ossification/calcification on imaging is
in favour of AML.

26.  DSA - angiography
 Angiomyolipomas are hypervascular
lesions demonstrating often
characteristic features:
micro or macro aneurysms
sharply marginated
dense early arterial network
late whorled appearance
absent AV shunting

27. Renal lymphangiectasia
 is a rare disorder
 dilatation of perirenal, peripelvic and intrarenal lymphatics.
 aspiration of chylous fluid is usually confirmatory.
 Haematuria, flank pain and abdominal pain
 Ascites, renal mass, pyelonephritis and renal insufficiency have also
been described
 Subscapular fluid accumulation  relative ischemia Secondary
Hypertension.
 Renal or perinephric inflammation, blocking the lymphatics

28. IMAGING
 USG:
 perirenal collection and peripelvic cysts
 retroperitoneal fluid collection
 ascites
 poor corticomedullary differentiation and diffuse
echogenic renal parenchyma
CT:
perinephric fluid attenuation collection of HU usually 0-
10.
Fluid collection in peritoneal or retroperitoneum
compartments
Perinephric collection may give a page kidney like
appearance.

30. MIXED EPITHELIAL AND STROMAL
TUMORS (MESTs)
 This comprises of tumors previously referred to as hamartoma,
adult mesoblastic nephroma.’
 seen almost exclusively in perimenopausal women, most patients
receiving estrogen therapy
 imaging patterns including complex cysts, mixed solid cystic masses
 show delayed and heterogeneous enhancement.
 On MR imaging the degree of delayed enhancement and T2
hypointense signal

31. It is typically seen as a multiloculated cystic renal mass with a
variable proportion of solid and cystic components and containing
internal septa. The latter may demonstrate heterogeneous and
delayed contrast material enhancement

32. CYSTIC NEPHROMA
 These are rare benign neoplasms that also show a female
preponderance. Most patients are asymptomatic
 predominantly unilateral,
 As well circumscribed cystic lesions with thin septations.
 Hemorrhage or urinary obstruction may be caused by the
prolapse of the cystic mass into the renal pelvis.

33. Renal Cysts and Bosniack classification
 The Bosniak classification system of renal cystic
masses divides renal cystic masses into five groups.
 based on imaging characteristics on contrast-enhanced CT
 Useful in predicting risk of malignanacy and follow up
Classification
 Bosniak 1
 simple cyst, imperceptible wall, rounded
 work-up: nil
 percentage malignant: ~0%

34.  Bosniak 2
 minimally complex, a few thin (<1 mm) septa, thin
calcifications;
 non-enhancing high-attenuation (due to to proteinaceous
or haemorrhagic fluid)
 renal lesions of less than 3 cm are also included in this
category;
 these lesions are generally well marginated
 work-up: nil
 percentage malignant: ~0%

35.  Bosniak 3
 indeterminate, thick or multiple
septations, mural nodule, hyperdense
on CT (see 2F)
 treatment/work-up: partial
nephrectomy or radiofrequency
ablation in elderly or poor surgical
candidates
 percentage malignant: ~54%

36.  Bosniak 4
 clearly malignant, solid mass with large
cystic or necrotic component
 treatment: partial or total nephrectomy
 percentage malignant: ~100

38. Incidental Solid Renal mass
 If a large >3 cm solid mass is discovered, renal cell carcinoma (provided
there is no fat on CT/MR protocols) is the most probable diagnosis and
surgery is recommended. If
 the tumor is 1-3 cm in size, RCC is most likely though percutaneous
biopsy may be required.
 Very small lesions < 1 cm are more likely to be benign; thin sections (< 3
mm) used .
 Obsevation and follow up CT/MR at 3-6months, then at 12 months and
then yearly may be done.

39. Urinary bladder Tumors
 Epithelial and no –epithelial
 All epithelial tumors are malignant ;
E.g transitional cell type with squamous cell carcinoma and adenocarcinoma.
 Non-epithelial tumors may be benign
E.g leiomyoma, fibroma
Malignant
E.g Leiomyosarcoma and Rhabdomyosarcoma
 Various other primary tumors or masses may occur including pheochromocytoma,
hemangioma, leukoplakia, lymphoma and endometriosis

40. Urinarybladder leiomyoma
 the most common mesenchymal tumor
 accounts for only 0.43% of bladder tumors.
 Leiomyomas occur equally in men and women with a wide age range
of 22–78 years
 Most are small and asymptomatic and are discovered incidentally.
 However, large tumors manifest with symptoms such as hesitancy,
frequency, dribbling, hematuria, pressure from mass effect, or
urinary obstruction.
 Leiomyomas arise in the submucosa,
 but growth may be submucosal (7%), intravesical (63%), or
extravesical (30%)
USG:
smooth-walled homogeneous hypoechoic solid mass in the bladder with
thin echogenic surface
Can determine the nature od spread
reveal smooth-walled solid lesion with homogeneous echogenicity

41.  CT is accurate in detection and localization of these
lesions, by presenting it as hypodense mass
 contrast-enhanced CT scan the lesion is shown as a
moderately enhancing mass
MRI
 Better demonstrating sub mucosal origin of the tumour
 the preservation of the muscle layer
 The imaging characteristics are similar to uterine
leiomyomas:
 T1: intermediate signal intensity
 T2: low signal intensity
 degenerated leiomyomas have more heterogeneous signal
characteristics; cystic areas have high signal intensity
 T1 C+ (Gad): contrast enhancement is variable,
degenerated areas lack enhancement

43. Neurofibroma
 Neurofibromas of the bladder are rare,
 The bladder is the most common genitourinary site of a neurofibroma.
 They may be isolated or occur in association with neurofibromatosis type 1
 Patients most commonly present with urinary tract infections. Other symptoms
include hematuria, urinary frequency and urgency, mass, or obstruction

44.  Characteristic CT and MR imaging features are diffuse, nodular
bladder wall thickening with masses extending to the pelvic side
wall .
 MR imaging features are more specific
 Low signal intensity on T1-weighted images
 a target sign on T2-weighted images.
 which consists of low-signal-intensity fibrosis surrounded by high-
signal-intensity myxoid stroma

46. Bladder Hemangiomas
 half manifest in childhood
 the mean age is 58 years (range, 19–76 years) and they are more
common in males in a ratio of 3.7:1
 Painless gross hematuria is the most common presentation
 a median size of 0.7 cm (range, 0.2–3 cm)
 . Cavernous hemangioma is the most common type, accounting for 78%
of cases,
capillary and arteriovenous types having equal rates of 10%

47.  Most were single, broad-based, sessile bladder masses on the
posterolateral walls
 Hemangiomas are hypervascular masses at US, CT, and MR imaging
 a focal, lobular, intramural mass OR diffuse bladder wall thickening
MRI
 low to intermediate signal intensity on T1-weighted images
 markedly high signal intensity on T2-weighted images

49. Paraganglioma
 preferred term for pheochromocytomas arising outside the adrenal gland.
 may rarely manifest as a bladder mass.
 They account for 0.1% of all bladder tumors and 1% of all
pheochromocytomas.
 The age range is wide at 10–78 years, and there is a female preponderance
 A characteristic clinical syndrome of catecholamine release during
micturition, “micturition attack,” occurs in 50% of patients.
 Nonfunctioning pheochromocytomas are also reported.

50.  CT
 a solid, homogeneous, lobulated, well-
marginated mass, but cystic areas may
result from necrosis or hemorrhage.
 Submucosal in location and marked
enhancement Post contrast .
 Ring calcification around the
circumference of the mass is highly
suggestive of a bladder paraganglioma

51. Prostate cyst
 Midline prostatic cysts can be Müllerian duct cysts or utricle cysts.
 Müllerian duct cysts do not contain sperms and can cause infertility due to
compression of the ejaculatory ducts.
 Utricle cysts contain sperms but unlike former do not extend beyond
prostate.
 The paramidline cysts are Wolffian cysts, seminal vesicle cysts or
ejaculatory duct cysts which contain sperms.
 Associated Wolffian duct anomalies, i.e. renal anomalies may be seen in
these patients
 Peripheral cysts are acquired retention cysts and may be associated with
BPH.
 Cowper’s gland cysts are also acquired cysts associated with urogenital
diaphragm.
 Cystic lesions appear smooth walled, hypoechoic on USG
 MRI: hyperintense on T2WI unless complicated by infection or hemorrhage

52. Adrenal Tumors

53. Pheochromocytoma
 catecholamine producing tumors which arise from ganglion cells.
 Arise from anywhere in the autonomic nervous system.
 Ninety percent of pheochromocytomas originate in the adrenal medulla,
 10 percent are extra-adrenal,
the common sites being paravertebral sympathetic ganglia, organ of Zuckerkandl,
urinary bladder, neck or mediastinum.
 10 percent are extra-adrenal, Ten percent of pheochromocytomas are bilateral
and 10 percent are malignant..
 Clinical features of hypertension, paroxysmal attacks of palpitation, headache,
sweating
 biochemical tests of plasma catecholamine levels and 24 hours urine
vanillylmandelic acid level can provide the diagnosis

54. IMAGING
 USG : seen as well-defined hypoechoic mass which
may show areas of necrosis or hemorrhage.
 Accuracy for detection is less than that of CT MRI
 CT is the technique of choice to confirm adrenal
mass.
 It is seen as soft tissue density mass with contrast
enhancement on CECT

55.  MRI
 MRI is the most sensitive modality for identification of pheochromocytomas, and is
particularly useful in cases of extra-adrenal location. The overall sensitivity is said to
be 98%
 T1
 slightly hypo-intense to the remainder of the adrenal
 if necrotic and/or haemorrhagic then signal will be more heterogeneous
 T2
 markedly hyper-intense
 areas of necrosis/haemorrhage/calcification will alter signal
 T1 C+ (Gd)
 heterogenous enhancement
 enhancement is prolonged, persisting for as long as 50 minutes

56. Adrenal adenomas
 Represent nonneoplastic overgrowth of adrenocortical cells of zona fasciculata.
 Consist of cholesterol laden clear cells and contribute little to steroid production
 Functional and non functional types are seen
 Imaging wise both appear the same.
 They account for almost 90 percent of all incidentalomas
CT: Low attenuation well defgined mass (HU values rarely exceed 10HU).
Contrast study shows enhancement with washout in delayed phase

57. Mri

58. Adrenal Adenoma V/s Metastasis
 Adrenal adenomas have two properties that differentiate them
from non-adenomas.
 . 70% of adenomas contain high intracellular fat (lipid-rich
adenomas) and will be of low attenuation on unenhanced CT.
 2. Adenomas rapidly wash out contrast.
 Unenhanced CT : HU values less than 10HU  Adenoma
 If > 10HU then Contrast CT

59.  Contrast CT :
 Mild with rapid washout Adenoma
 Hetrogenous moderate to intense enhancement Malignant or
 Pheochromocytoma
 The wash-out can be calculated by comparing the attenuation value at
60 sec with the attenuation value on a delayed scan at 15 minutes.

61. Adrenal Cyst
 Adrenal cysts are rare and usually seen in females.
 derived from endothelium in 45 percent of patients
 the rest are epithelial, parasitic or pseudocysts from prior hemorrhage.
 CT shows characteristically well-defined round low attenuating lesion suggesting fluid
with rim enhancement
 Rim calcification may be noted
 The attenuation values may be mixed in the presence of debris or hemorrhage

62. Adrenal Myelolipoma
 benign tumor of the cortex, comprised of mature fat and hematopoietic elements
 It accounts for about 7-15 percent of all incidentalomas.
 Imaging appearance may vary depending on which histological component is
dominant
USG : well-defined echogenic or heterogeneous adrenal mass,
 may be associated with apparent posterior displacement of the diaphragm.
CT:
confirms presence of intratumoral fat.
 Punctate calcification may be seen in 20 percent of cases
 large myelolipomas may mimic retroperitoneal lipoma or liposarcoma.

64. GRE T1W in-phase (A)
and opposed phase (B)
image show a
hyperintense
right adrenal mass
which shows no drop in
signal intensity but is
suppressed on
T2W fat suppressed
image

65. Spotters

67. Double bubble sign

69. PINCER TYPE IMPINGEMENT

71. Lipoma of the filum terminale
is a relatively common finding on imaging of the lumbar
spine, and in most cases is an incidental finding of no
clinical concern.
In some patients however it may be associated with signs
and symptoms of tethered cord syndrome.
In such cases it is usually associated with a thickened filum
and a low lying conus

75. Hamburger’s sign

76. THANK YOU