Renal Donors

Defining renal vascular anatomy is essential for the evaluation of potential living-related kidney donors because anatomic variants occur in an estimated 12% to 44% of cases. Accessory arteries perfusing more than 5% of the renal parenchyma must not be sacrificed. But multiple arterial anastomoses may result in an increased risk of thrombosis, malperfusion, and finally rejection. Early branching renal arteries may also complicate harvesting and implantation of the renal allograft. Thus, failure to identify accessory renal arteries before surgery can complicate the transplantation procedure and may compromise the outcome. Accurate determination of the number, length, and location of renal arteries is essential for proper surgical planning, especially with the minimally invasive techniques. It is also important to identify anatomic variations in the renal venous and parenchymal anatomy (Fig. 18).

CE MRA is ideal for assessing renal vessels and renal parenchyma in potential living kidney donors [ 18-22]. CE MRA shows the arterial system, venous system, and collecting system as well as the kidney parenchyma using multi-phase coronal 3D CE MRA. It may be helpful to follow Gd injection with 10 mg lasix to more completely fill out the colleting systems on a 10-minute delayed image for MR urographic evaluation. In interpreting MRA images, it is necessary to analyze source images and data in the reformation mode. The data must be viewed in both the coronal and axial planes. Axial reformation allows easy differentia-

Mra Phase Contrast Lumbar
Fig. 18. Horseshoe kidney on CE MRA

tion between lumbar arteries, accessory renal arteries, and overlying mesenteric arterial branches. MRA provides sufficient information about the renal arterial anatomy and is superior in diagnosing the anatomy of the renal veins in the evaluation of living kidney donors [23,24]. One potential limita-

Table 1. Sensitivity and specificity of renal MR angiography without contrast agents

Technique

Author

Year

# Patients

Sensitivity (%)

Specificity (%)

2D TOF

Kent [49]

1991

23

100

94

2D TOF

Debatin [50]

1991

33

53

97

2D TOF

Servois [51]

1994

21

70

78

2D TOF

Hertz [52]

1994

16

91

94

3D TOF

Loubeyre [53]

1994

53

100

76

3D TOF

Nelson [54]

1999

5

71

95

2D PC

Debatin (50)

1991

33

80

91

3D PC

De Cobelli [55]

1996

50

94

94

Cine PC

Silverman [56]

1996

37

100

93

3D PC

de Haan [57]

1996

38

93

95

3D PC

Miller [58]

1999

32

93

81

3D PC - PSL*

Westenberg [59]

1999

17

Correlation coefficient = 0.90

Cine-PC

Lee [40]

2000

35

50

78

Cine-PC +ACE**

67

84

T2 dark blood

Tello [7]

2003

16

96

92

* post-stenotic signal loss ** angiotensin-converting enzyme

tion is the inability of MR to detect renal calculi, however these are rare in the asymptomatic renal donor population.

Was this article helpful?

0 0
Your Heart and Nutrition

Your Heart and Nutrition

Prevention is better than a cure. Learn how to cherish your heart by taking the necessary means to keep it pumping healthily and steadily through your life.

Get My Free Ebook


Post a comment