1.Upper urinary tract trauma 2.Renal and ureteric calculi

1. 1.Upper urinary tract trauma
2.Renal and ureteric calculi
Dr.Aftab Qadir

2. 1.Renal trauma
• Up to 90% of renal injury is due to blunt injury
• 10% of patients with significant abdominal trauma
• Pre exisiting renal abnormalities e.g. vulnerable position
• Pediatric kidney is also more vulnerable
Imaging is done in patient
• gross haematuria or microscopic haematuria with other
signs of renal damage e.g. shock
• history of sustained substantial trauma to the renal area

4. Imaging
IVU
• It may offer confirmation for the presence of a
functioning contra lateral kidney
• The absence of unilateral excretion suggests a major
vascular injury
• Disruption of the pelvicalyceal system may be seen as
extravasation of opacified urine.
One shot intravenous Urography

6. Ultrasound
Extensively used in trauma.
• Subcapsular and perinephric haematoma can be seen
• Acutely seen as echo-poor areas, becoming more
heterogeneous and echogenic with time.
• Disruption of renal parenchyma with capsular tears.
• Color flow and spectral Doppler may allow diagnosis of
pedicle injuries.
• Significant renal injuries may be missed, with up to 80%
of parenchymal lesions being overlooked.
Detecting hemoperitoneum

8. CT
• Currently the imaging modality of choice
• Entire abdomen, including the liver and spleen evaluated
for coexistent injuries
• Multiplanar reformatted and three-dimensional images
• Haematoma may be parenchymal, subcapsular,
perinephric or any combination of these
• Early and delayed scans are done

9. • Subcapsular blood is seen as a cresentic low-density area
following the convexity of the outer aspect of the renal
cortex.
• Perinephric haematoma surrounds the kidney as it
enlarges mostly posterior, displacing the kidney forwards
• If the collection is predominantly medial, pelviureteric
disruption should be considered.
• Renal lacerations/tears appear as irregular low-density
linear areas crossing the parenchyma .

10. • Fractures are lacerations that extend from the hilum to
the external surface of the kidney
• Multiple renal fragments are referred to as a shattered
kidney
• The commonest vascular injury to the kidney is renal
artery disruption/avulsion, which appears as
non-perfusion of the kidney.

11. Renal contusion (category I) in a 46-year-old man who had sustained
blunt abdominal trauma. Contrast-enhanced nephrographic-phase
helical CT scan demonstrates a focal area of decreased contrast
enhancement in the interpolar region of the left kidney (arrowhead).

12. Subcapsular hematoma (category I) in a 40-year-old man who had
sustained blunt abdominal trauma.
Contrast-enhanced helical CT scan demonstrates a subcapsular fluid
collection (straight white arrows) flattening the posterolateral contour of
the left kidney. There is minimal cortical laceration (black arrow). Note
also the subcutaneous emphysema in the left side of the back (curved
arrow)

13. Simple renal laceration (category I) in a 30-year-old woman who had
sustained blunt abdominal trauma.
Contrast-enhanced multidetector helical CT scan reveals a small,
hypoattenuating laceration crossing the interpolar region of the left kidney
(white arrow) associated with a limited perinephric hematoma.
A hepatic laceration (black arrow) and hemoperitoneum in the Morrison
pouch (arrowheads) are also seen.

14. (a) Contrast-enhanced generalized-nephrographic-phase helical CT scan
reveals what appears to be only a large perinephric hematoma (H) secondary
to a distinct renal laceration (not shown). Because this is an early-phase
image, there is no contrast material in the collecting system. The descending
colon (C) is displaced anteriorly by the hematoma. (b) Excretory-phase CT
scan demonstrates extensive extravasation of contrast-enhanced urine
admixed with the hematoma, a finding that demonstrates that the laceration
has disrupted the integrity of the collecting system.

15. Subsegmental renal infarction (category I) in a 47-year-old man who had
sustained blunt abdominal trauma. Contrast-enhanced CT scan demonstrates
a sharply demarcated, wedge-shaped area of decreased attenuation in the
interpolar region of the right kidney (solid arrow). Note also the evidence of
subtle hemorrhage in the right renal hilum (open arrow).

16. Major renal laceration without involvement of the collecting system (category
II) in a 32-year-old woman who had sustained blunt abdominal trauma.
Contrast-enhanced helical CT scan reveals a laceration in the posterolateral
aspect of the middle portion of the left kidney (arrows) associated with
perinephric hematoma.

17. Contrast CT showing large predominantly posterior
perinephric hemorrhage.

18. Demonstrating traumatic rupture of a pre-existing pelviureteric
junction obstruction following relatively minor trauma.
There is copious extravasation of urine and contrast medium

19. Contrast CT showing a fracture through the centre of the kidney with
considerable circumferential perinephric haemorrhage (A).
Two months after conservative management there has been impressive
healing of the kidney and resorption of most of the haemorrhage (B).

20. Ruptured renal cyst with pericystic fluid

21. Most widely used imaging classification of renal injuries is
by Federle.
• categorizing injuries into four groups (minor, major,
catastrophic and injuries to the pelviureteric junction).
The American Association of Surgery (AAST) have
described a surgical classification

24. AmericanAssociationofSurgery ofTrauma(AAST)

26. • 95% of renal trauma is represented by minor lacerations
and parenchymal contusions and does not require
surgery.
• Most major lacerations will heal without intervention,
even with a shattered kidney
• Perinephric collections of urine or blood will tend to
resorb over time.
• Large and/or infected collections may be treated with
percutaneous drainage.

27. Contrast CT of traumatic renal arterial avulsion. The left kidney is
completely non-enhancing (non-perfused). There is a small amount
of blood along the line of the renal vessels and a modest
haemorrhage related to the spleen.

28. Stab wound resulting in laceration of the lower pole of the right kidney
with considerable associated hematoma shown on contrast CT

29. Ureteric trauma
• constitutes less than I % of urinary tract trauma.
• more frequent in children
• acquired through medical intervention, e.g.
gynecological surgery for malignancy.
• On IVU there may be mild to moderate fullness of the
pelvicalyceal system and extravasations at the site of the
tear
• contrast extravasations, formation of a urinoma and
occasionally ureteric discontinuity.
• Fistulation into other structures may occur

30. Bilateral extravasation from the distal ureters following radical pelvic surgery.
The ureters also show smooth tapered stricturing in the pelvis with bilateral
hydronephrosis and dilatation of the proximal ureters, worse on the right

31. Damage to the left ureter during pelvic surgery with severe distal
ureteric stricturing, extravasation and fistulation into the vagina arrow
indicates contrast in the vagina.

32. 69 year old male. Contrast enhanced (left) and delayed (right) CT scans
demonstrating low density fluid around the left kidney and ureter, and
contrast extravasation from the proximal left ureter

33. Complications in Renal Injury
Early complications
• urinary extravasation and urinoma formation, delayed
bleeding, infected urinoma, perinephric abscess, sepsis,
arteriovenous fistula, pseudoaneurysm
Late complications
• include hydronephrosis, hypertension, calculus
formation, and chronic pyelonephritis

34. Recommended article
• Imaging of Renal Trauma: A Comprehensive Review
• http://pubs.rsna.org/doi/full/10.1148/radiographics.21.3.g0
1ma11557
• Abdominal Trauma Imaging
• http://www.intechopen.com/books/abdominal-
surgery/abdominal-trauma-imaging
• Current Role of Emergency US in Patients with Major Trauma
• http://pubs.rsna.org/doi/full/10.1148/rg.281075047

35. 2.Renal and ureteric calculi

36. Renal calculi
• Form due to minerals crystallizing out of urine in a normal
urinary tract.
• Hyperealciuria is the most common
• Highly radiopaque, particularly calcium phosphate calculi.
• Small-bowel disease or resection predisposes particularly
to the formation of oxalate calculi, which may have a
speculated or punctate appearance
• Calculus may become large and branching (staghorn, i.e.
extending into adjacent calyces

39. • Over 90% of calculi are radiopaque on plain films
• Virtually all are seen on CT

40. • Small calculi that remain in the calyces are generally
asymptomatic
• Migration of small calculi into the ureter is common and
presents with colic.
• There is usually haematuria

42. KUB
• Plain abdominal radiography
• assessing total stone burden, as well as the size, shape
• location of urinary calculi
• Calcium-containing are radiopaque
• the progress of the stone can be easily monitored with a
follow-up KUB
Many calcifications on the KUB radiograph are:
• phleboliths, vascular calcifications, calcified lymph
nodes, appendicoliths, granulomas or even bowel
contents.

43. Larger calculus in the left lower pole major calyx.

44. Plain film showing large right staghorn calculus.

45. IVU
• The traditional modality for investigating ureteric calculi
• In most patients with ureteric colic there is some degree
of obstruction, manifested by delay in the appearance of
the nephrogram and contrast excretion into the
pelvicalyceal system.
• The affected kidney is often modestly enlarged
• Calculi are seen as filling defects on the post contrast film
• Acute ureteral obstruction causes an intense persistent
nephrograms.
• CT scanning has replaced IVP

46. Intravenous pyelogram (IVP) demonstrating dilation of
the right renal collecting system and right ureter
consistent with right ureterovesical stone.

47. Full length film from an IVU series (A) showing stasis and mild fullness in the
left ureter and considerable oedema around the vesicoureteric junction due
to a small calculus visible on the plain film (B

50. • Ultrasound usually demonstrates mild hydronephrosis
sensitivity (95%) but at the cost of a low specificity of
around 67%
• Highly echogenic foci with dense distal acoustic
shadowing
• Vesicoureteric junction
• relies on indirect visualization clues to identify stones
• less accurate than IVP or CT in diagnosis of ureteral
stones
• does not help in the evaluation of kidney function.
Ultrasound

51. • 35% of patients acute ureteral obstruction do not
demonstrate any significant hydroureteronephrosis
• not reliable for small stones smaller than 5 mm
• dependent on operator skill

55. Grades of hydronephrosis

58. • Sonographic Mimics of Renal Calculi
• http://www.jultrasoundmed.org/content/23/10/1361.full

59. • CT KUB is very good at picking up small and large calcified
stones in the kidneys
• unenhanced CT scan of the abdomen and pelvis very narrow
cuts taken through the kidneys and bladder areas
• contrast obscures calcific densities
• the patient’s bladder is filled, which facilitates viewing the
ureterovesical junction

60. Advantages of CT scanning
• It can reveal other pathology (e.g., AAAs, appendicitis,
pancreatitis, cholecystis, ovarian disorders, diverticular
disease, renal carcinoma).
• It can be performed quickly (< 5 min acquisition time)
• It avoids the use of IV contrast materials.
• The density of the stone can assist in predicting stone
composition and response to shockwave lithotripsy.

61. • Spiral CT is now increasingly replacing the IVU
• sensitivity of 94%, and specificity of 97%
• exposes the patient to a significant radiation
• Essentially all ureteric calculi are radiopaque on CT
• Calculi usually demonstrate a rim of soft tissue, which helps
distinguish them.
• The obstructed kidney may also be enlarged
• There is often stranding within the perinephric fat
• The pyramids may normally appear remarkably dense on
unenhanced CT (white pyramid sign)

62. Bilateral calcific densities near the vesicoureteric junctions. Right calcific
density (red arrow) is completely surrounded by a soft tissue density rim
consistent with a ureteric stone surrounded by an oedematous ureter wall
(soft tissue rim sign). The left calcific density (green arrow) cannot be a
ureteric stone as it is completely surrounded by fat density and it is
therefore a phlebolith.

64. Computed tomography shows a stone, of calcific density, at the level of right
distal ureter, which determines periureteral inflammation and produces a
mild hydroureteronephrosis in the ipsilateral kidney.

65. Non contrast helical CT scan of the abdomen demonstrating a stone
at the right vesicoureteric junction.

66. Hydronephrosis and hydroureter
Major causes of obstructive hydronephrosis:
• Calculi-renal pelvic (hydronephrosis alone), ureteric
• Pelviureteric junction obstruction
• Tumours
• Inflammatory mass lesions
• Retroperitoneal fibrosis
• Pregnancy hydronephrosis and hydroureter.

67. • prolonged obstruction there may be almost complete
cortical loss.
• Spectral analysis of interlobar or arcuate arteries may
demonstrate increase in the resistive index in the
obstructed kidney. This reflects reduction in the blood
flow and is seen in a number of other conditions,
including acute renal parenchymal disease.
• A resistive index above 0.70, or more than 0.08 more
than the contralateral kidney, is suggestive of obstruction
in the appropriate clinical situation.

68. Few Cases

70. Subcapsular hematoma (Page kidney) in a 30-year-old woman with a history
of a seizure disorder who presented with right flank pain and hypertension.
Contrast-enhanced spiral CT scan demonstrates a subcapsular fluid collection
(H) flattening the right kidney. The patient underwent successful US-guided
percutaneous drainage of the hematoma.

71. What we see on the right is not a laceration, because it is not linear.
It is not a contusion, because it is sharply demarcated.
This is an post traumatic segmental infarction.

72. Axial contrast-enhanced CT scan image in venous phase: Shattered
kidney with ureteropelvic junction rupture and extravasation of
contrast media and avulsion of renal hilum that devascularizes the
kidney (grade V AAST renal injury)

73. Renal hematoma and a small perirenal hematoma

74. Thank You