The document discusses unilateral small kidneys and the role of imaging in establishing a diagnosis. It describes various causes of unilateral small kidneys including pre-renal issues like renal artery stenosis, intra-renal issues such as renal infarction, and post-renal issues like reflux nephropathy. Imaging modalities like ultrasound, CT, MRI, renal scintigraphy, and angiography are discussed for evaluating the kidneys and determining the underlying etiology. The document emphasizes how different imaging findings can help identify conditions that may cause one kidney to be smaller than the other.

1. BY
DR.MAIMUNA A. HALLIRU
RADIOLOGY DEPARTMENT
AMINU KANO TEACHING HOSPITAL
02-09-2013

2.  INTRODUCTION
 CAUSES OF UNILATERAL SMALL KIDNEY
 ROLE OF IMAGING IN ESTABLISHING A
DIAGNOSIS
 SUMMARY/CONCLUSION

3.  DEFINITION OF UNILATERAL
SMALL KIDNEY

4.  PRE-RENAL/VASCULAR
 INTRA-RENAL/PARENCHYMAL
 POST-RENAL/COLLECTING SYSTEM

5.  RENAL ARTERY STENOSIS

6. NORMAL PATTERN: RAPID
UPSTROKE & EARLY
SYSTOLIC PEAK (ARROW)
TARDUS & PARVUS
WAVEFORM: SLOWED
UPSTROKE & LOW
AMPLITUDE PEAK

7. Delayed nephrogram on CT

8. CT- arterial phase :
Differential perfusion

10. DENSE PERSISTENT NEPHROGRAM
WITH POOR EXCRETION OF
CONTRAST MEDIUM

11. BILATERAL RENAL
ARTERY STENOSIS

13. BEADED, ANEURYSMAL
APPEARANCE OF THE RIGHT RENAL
ARTERY IN FIBROMUSCULAR
DYSPLASIA

17. RENAL INFARCTION

18. (A) An initial nephrotomogram demonstrates a thin
cortical rim surrounding the right kidney (arrows),
reflecting viable renal cortex perfused by perforating
collateral vessels from the renal capsule. (B) Four months
later, a repeat nephrotomogram shows a marked decrease in
the size of the atrophic right kidney (arrowheads).

19. C+ portal venous phase CT demonstrates a wedge of
poorly / non-enhancing renal parenchyma at the upper pole

20. CT demonstrates a non-enhancing
thrombus extending into the renal vein

22. Heterogeneous mass at the
upper pole of the kidney.

23. Angiography showing a renal
infarction

24. RADIATION
NEPHROPATHY

26.  CONGENITAL HYPOPLASIA

27. SMALL LEFT KIDNEY WITH
PRESERVED ALBEIT REDUCED
RENAL FUNCTION

30. RENAL DYSPLASIA

31. Renal dysplasia in Laurence-Moon-Biedl
syndrome showing poorly developed papillae
and small communicating calyceal diverticula on
IVU.

32.  POST-INFECTIVE ATROPHY

33. Post infective scarring.
99mTc-DMSA study showing
normal left kidney; scarred right
upper pole (arrows)

34.  REFLUX NEPHROPATHY

35. Demonstrates bilateral diffuse calyceal
clubbing (arrows) and deformity
accompanied by thinning of the
adjacent renal parenchyma
(arrowheads)

36. Normal parenchymal thickness in the upper portion of the
kidney and generalized marked parenchymal thinning in the
lower portion. The latter reflects chronic pyelonephritic
scarring secondary to urinary tract infection and
vesicoureteral reflux that occurred in childhood.

38.  POST-OBSTRUCTIVE
ATROPHY

41.  CONVENTIONAL RADIOGRAPHY

42. ULTRASONOGRAPHY:
B-MODE & DOPPLER

43. Normal parenchymal thickness in the upper portion of the
kidney and generalized marked parenchymal thinning in the
lower portion. The latter reflects chronic pyelonephritic
scarring secondary to urinary tract infection and
vesicoureteral reflux that occurred in childhood.

44. Heterogeneous mass at the
upper pole of the kidney.

45. NORMAL PATTERN: RAPID
UPSTROKE & EARLY
SYSTOLIC PEAK (ARROW)
TARDUS & PARVUS
WAVEFORM: SLOWED
UPSTROKE & LOW
AMPLITUDE PEAK

46.  INTRAVENOUS UROGRAPHY

47. DENSE PERSISTENT NEPHROGRAM
WITH POOR EXCRETION OF
CONTRAST MEDIUM

48. (A) An initial nephrotomogram demonstrates a thin
cortical rim surrounding the right kidney (arrows),
reflecting viable renal cortex perfused by perforating
collateral vessels from the renal capsule. (B) Four months
later, a repeat nephrotomogram shows a marked decrease in
the size of the atrophic right kidney (arrowheads).

49. SMALL LEFT KIDNEY WITH
PRESERVED ALBEIT REDUCED
RENAL FUNCTION

50.  COMPUTED
TOMOGRAPHY/CTA

51. NARROWED SEGMENT OF LEFT MAIN
RENAL ARTERY
COMPUTED TOMOGRAPHY

52. CORTICAL DEFECTS ON CECT IN RENAL
INFARCTION

53. RENAL SCARRING IN REFLUX
NEPHROPATHY

54.  MAGNETIC RESONANCE
IMAGING/ MRA

55. RENAL ARTERY STENOSIS

56. RENAL HYPOPLASIA

57. RENAL SCINTIGRAPHY

59. Post infective scarring.
99mTc-DMSA study showing
normal left kidney; scarred right
upper pole (arrows)

61.  DIGITAL SUBTRACTED
ANGIOGRAPHY

62. BILATERAL RENAL
ARTERY STENOSIS

64. Angiography showing a renal
infarction

65.  CONCLUSION/SUMMARY