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MR Imaging: A "One-Stop Shop" Modality for Preoperative Evaluation of Potential Living Kidney Donors¹

¹ From the Departments of Radiology (S.M.H., M.C.J.M.K., P.M.T.P., M.G.M.H., G.P.K.), Epidemiology and Biostatistics (M.C.J.M.K., M.G.M.H.), and Surgery (J.N.M.I.), Erasmus Medical Center, Dr Molewaterplein 40, 3015 GD Rotterdam, the Netherlands. Recipient of an Excellence in Design award for an education exhibit at the 2001 RSNA scientific assembly. Received March 21, 2002; revision requested May 2 and received June 24; accepted June 25. Address correspondence to S.M.H.

View larger version (105K): [in a new window]   Figure 1a.  MR imaging protocol for evaluation of living kidney donors. (a) Coronal T2-weighted single-shot fast spin-echo (SE) or half-Fourier single-shot turbo SE image shows the kidneys (arrows), which have low signal intensity relative to their surroundings. This sequence allows simple and reproducible measurement of both kidneys. (b) Sagittal T2-weighted single-shot fast SE or half-Fourier single-shot turbo SE image shows the right kidney (arrow) in a different orientation. (c) Axial fat-saturated T2-weighted fast SE image shows both kidneys (straight arrows), which are hyperintense relative to their surroundings. Note the aorta (arrowhead) and inferior vena cava (IVC) (curved arrow), which demonstrate signal void due to flow compensation. (d) Coronal gadolinium-enhanced T1-weighted three-dimensional (3D) fast gradient-echo (GRE) source image shows the strongly enhanced aorta (straight arrow) and renal arteries (curved arrows). Before acquisition of this gadolinium-enhanced data set, an identical unenhanced sequence is performed to assess the patient’s breath-holding ability and to obtain any subtraction images needed for postprocessing. (e) Coronal T1-weighted 3D fast GRE image obtained during the venous phase shows enhancement of the IVC (curved arrow) and aorta (straight arrow). (f) Axial delayed gadolinium-enhanced T1-weighted 3D fast GRE image obtained with fat saturation shows homogeneous enhancement of both kidneys (large straight arrows) and enhancement of the left renal vein (arrowhead) and IVC (curved arrow). Note that the right renal artery (small straight arrow) runs behind the IVC.

View larger version (81K): [in a new window]   Figure 1b.  MR imaging protocol for evaluation of living kidney donors. (a) Coronal T2-weighted single-shot fast spin-echo (SE) or half-Fourier single-shot turbo SE image shows the kidneys (arrows), which have low signal intensity relative to their surroundings. This sequence allows simple and reproducible measurement of both kidneys. (b) Sagittal T2-weighted single-shot fast SE or half-Fourier single-shot turbo SE image shows the right kidney (arrow) in a different orientation. (c) Axial fat-saturated T2-weighted fast SE image shows both kidneys (straight arrows), which are hyperintense relative to their surroundings. Note the aorta (arrowhead) and inferior vena cava (IVC) (curved arrow), which demonstrate signal void due to flow compensation. (d) Coronal gadolinium-enhanced T1-weighted three-dimensional (3D) fast gradient-echo (GRE) source image shows the strongly enhanced aorta (straight arrow) and renal arteries (curved arrows). Before acquisition of this gadolinium-enhanced data set, an identical unenhanced sequence is performed to assess the patient’s breath-holding ability and to obtain any subtraction images needed for postprocessing. (e) Coronal T1-weighted 3D fast GRE image obtained during the venous phase shows enhancement of the IVC (curved arrow) and aorta (straight arrow). (f) Axial delayed gadolinium-enhanced T1-weighted 3D fast GRE image obtained with fat saturation shows homogeneous enhancement of both kidneys (large straight arrows) and enhancement of the left renal vein (arrowhead) and IVC (curved arrow). Note that the right renal artery (small straight arrow) runs behind the IVC.

View larger version (112K): [in a new window]   Figure 1c.  MR imaging protocol for evaluation of living kidney donors. (a) Coronal T2-weighted single-shot fast spin-echo (SE) or half-Fourier single-shot turbo SE image shows the kidneys (arrows), which have low signal intensity relative to their surroundings. This sequence allows simple and reproducible measurement of both kidneys. (b) Sagittal T2-weighted single-shot fast SE or half-Fourier single-shot turbo SE image shows the right kidney (arrow) in a different orientation. (c) Axial fat-saturated T2-weighted fast SE image shows both kidneys (straight arrows), which are hyperintense relative to their surroundings. Note the aorta (arrowhead) and inferior vena cava (IVC) (curved arrow), which demonstrate signal void due to flow compensation. (d) Coronal gadolinium-enhanced T1-weighted three-dimensional (3D) fast gradient-echo (GRE) source image shows the strongly enhanced aorta (straight arrow) and renal arteries (curved arrows). Before acquisition of this gadolinium-enhanced data set, an identical unenhanced sequence is performed to assess the patient’s breath-holding ability and to obtain any subtraction images needed for postprocessing. (e) Coronal T1-weighted 3D fast GRE image obtained during the venous phase shows enhancement of the IVC (curved arrow) and aorta (straight arrow). (f) Axial delayed gadolinium-enhanced T1-weighted 3D fast GRE image obtained with fat saturation shows homogeneous enhancement of both kidneys (large straight arrows) and enhancement of the left renal vein (arrowhead) and IVC (curved arrow). Note that the right renal artery (small straight arrow) runs behind the IVC.

View larger version (95K): [in a new window]   Figure 1d.  MR imaging protocol for evaluation of living kidney donors. (a) Coronal T2-weighted single-shot fast spin-echo (SE) or half-Fourier single-shot turbo SE image shows the kidneys (arrows), which have low signal intensity relative to their surroundings. This sequence allows simple and reproducible measurement of both kidneys. (b) Sagittal T2-weighted single-shot fast SE or half-Fourier single-shot turbo SE image shows the right kidney (arrow) in a different orientation. (c) Axial fat-saturated T2-weighted fast SE image shows both kidneys (straight arrows), which are hyperintense relative to their surroundings. Note the aorta (arrowhead) and inferior vena cava (IVC) (curved arrow), which demonstrate signal void due to flow compensation. (d) Coronal gadolinium-enhanced T1-weighted three-dimensional (3D) fast gradient-echo (GRE) source image shows the strongly enhanced aorta (straight arrow) and renal arteries (curved arrows). Before acquisition of this gadolinium-enhanced data set, an identical unenhanced sequence is performed to assess the patient’s breath-holding ability and to obtain any subtraction images needed for postprocessing. (e) Coronal T1-weighted 3D fast GRE image obtained during the venous phase shows enhancement of the IVC (curved arrow) and aorta (straight arrow). (f) Axial delayed gadolinium-enhanced T1-weighted 3D fast GRE image obtained with fat saturation shows homogeneous enhancement of both kidneys (large straight arrows) and enhancement of the left renal vein (arrowhead) and IVC (curved arrow). Note that the right renal artery (small straight arrow) runs behind the IVC.

View larger version (115K): [in a new window]   Figure 1e.  MR imaging protocol for evaluation of living kidney donors. (a) Coronal T2-weighted single-shot fast spin-echo (SE) or half-Fourier single-shot turbo SE image shows the kidneys (arrows), which have low signal intensity relative to their surroundings. This sequence allows simple and reproducible measurement of both kidneys. (b) Sagittal T2-weighted single-shot fast SE or half-Fourier single-shot turbo SE image shows the right kidney (arrow) in a different orientation. (c) Axial fat-saturated T2-weighted fast SE image shows both kidneys (straight arrows), which are hyperintense relative to their surroundings. Note the aorta (arrowhead) and inferior vena cava (IVC) (curved arrow), which demonstrate signal void due to flow compensation. (d) Coronal gadolinium-enhanced T1-weighted three-dimensional (3D) fast gradient-echo (GRE) source image shows the strongly enhanced aorta (straight arrow) and renal arteries (curved arrows). Before acquisition of this gadolinium-enhanced data set, an identical unenhanced sequence is performed to assess the patient’s breath-holding ability and to obtain any subtraction images needed for postprocessing. (e) Coronal T1-weighted 3D fast GRE image obtained during the venous phase shows enhancement of the IVC (curved arrow) and aorta (straight arrow). (f) Axial delayed gadolinium-enhanced T1-weighted 3D fast GRE image obtained with fat saturation shows homogeneous enhancement of both kidneys (large straight arrows) and enhancement of the left renal vein (arrowhead) and IVC (curved arrow). Note that the right renal artery (small straight arrow) runs behind the IVC.

View larger version (95K): [in a new window]   Figure 1f.  MR imaging protocol for evaluation of living kidney donors. (a) Coronal T2-weighted single-shot fast spin-echo (SE) or half-Fourier single-shot turbo SE image shows the kidneys (arrows), which have low signal intensity relative to their surroundings. This sequence allows simple and reproducible measurement of both kidneys. (b) Sagittal T2-weighted single-shot fast SE or half-Fourier single-shot turbo SE image shows the right kidney (arrow) in a different orientation. (c) Axial fat-saturated T2-weighted fast SE image shows both kidneys (straight arrows), which are hyperintense relative to their surroundings. Note the aorta (arrowhead) and inferior vena cava (IVC) (curved arrow), which demonstrate signal void due to flow compensation. (d) Coronal gadolinium-enhanced T1-weighted three-dimensional (3D) fast gradient-echo (GRE) source image shows the strongly enhanced aorta (straight arrow) and renal arteries (curved arrows). Before acquisition of this gadolinium-enhanced data set, an identical unenhanced sequence is performed to assess the patient’s breath-holding ability and to obtain any subtraction images needed for postprocessing. (e) Coronal T1-weighted 3D fast GRE image obtained during the venous phase shows enhancement of the IVC (curved arrow) and aorta (straight arrow). (f) Axial delayed gadolinium-enhanced T1-weighted 3D fast GRE image obtained with fat saturation shows homogeneous enhancement of both kidneys (large straight arrows) and enhancement of the left renal vein (arrowhead) and IVC (curved arrow). Note that the right renal artery (small straight arrow) runs behind the IVC.

View larger version (117K): [in a new window]   Figure 2a.  Timing bolus sequence. (a) Sagittal T1-weighted two-dimensional fast field echo image (free breathing) with a section thickness of 2 cm shows the aorta. To capture the peak enhancement of the aorta, approximately 40-50 images are acquired at a temporal resolution of about two images per second. This temporal resolution allows the operator to actually see the arrival of the contrast medium within the heart, thoracic aorta, and abdominal aorta. Imaging is stopped after about 25 seconds or continued till the peak enhancement of the abdominal aorta has been satisfactorily observed. Note the region of interest at the level of the large abdominal vessels (arrow). (b) Time-intensity curve generated from the region of interest in a shows that the peak enhancement of the aorta at the level of the large abdominal vessels occurs at 15.7 seconds. On the basis of this value, the imaging delay for the main 3D gadolinium-enhanced MR angiography sequence can be calculated as follows: imaging delay = (contrast material arrival time) + (injection time/2) - (imaging time/2).

View larger version (23K): [in a new window]   Figure 2b.  Timing bolus sequence. (a) Sagittal T1-weighted two-dimensional fast field echo image (free breathing) with a section thickness of 2 cm shows the aorta. To capture the peak enhancement of the aorta, approximately 40-50 images are acquired at a temporal resolution of about two images per second. This temporal resolution allows the operator to actually see the arrival of the contrast medium within the heart, thoracic aorta, and abdominal aorta. Imaging is stopped after about 25 seconds or continued till the peak enhancement of the abdominal aorta has been satisfactorily observed. Note the region of interest at the level of the large abdominal vessels (arrow). (b) Time-intensity curve generated from the region of interest in a shows that the peak enhancement of the aorta at the level of the large abdominal vessels occurs at 15.7 seconds. On the basis of this value, the imaging delay for the main 3D gadolinium-enhanced MR angiography sequence can be calculated as follows: imaging delay = (contrast material arrival time) + (injection time/2) - (imaging time/2).

View larger version (120K): [in a new window]   Figure 3a.  Postprocessing of an MR angiography data set from a living kidney donor. (a) Coronal full maximum intensity projection (MIP) image shows the aorta and its tributaries, including the main renal arteries (curved arrows), accessory renal arteries (straight arrows), and lumber arteries (arrowhead). (b) Coronal oblique linear reformatted image angled along the approximate course of the right renal vessels shows the main renal artery (curved arrow) and accessory renal artery (straight arrow) more clearly. (c) Coronal oblique linear reformatted image angled along the course of the left renal vessels shows the main renal artery (curved arrow), accessory renal artery (straight arrow), and lumber artery (arrowhead) more clearly. (d) Coronal targeted MIP image obtained at the origin of the renal arteries shows the relationship between the main renal arteries (curved arrows) and accessory renal arteries (straight arrows) and the lumber arteries (arrowhead). (e) Axial reformatted image clearly shows the main renal arteries (curved arrow) and accessory renal arteries (straight arrow) originating from the aorta. (f) Axial reformatted image obtained at a different level clearly shows the relationship between the renal artery (curved arrow) and the lumber artery (arrowhead).

View larger version (121K): [in a new window]   Figure 3b.  Postprocessing of an MR angiography data set from a living kidney donor. (a) Coronal full maximum intensity projection (MIP) image shows the aorta and its tributaries, including the main renal arteries (curved arrows), accessory renal arteries (straight arrows), and lumber arteries (arrowhead). (b) Coronal oblique linear reformatted image angled along the approximate course of the right renal vessels shows the main renal artery (curved arrow) and accessory renal artery (straight arrow) more clearly. (c) Coronal oblique linear reformatted image angled along the course of the left renal vessels shows the main renal artery (curved arrow), accessory renal artery (straight arrow), and lumber artery (arrowhead) more clearly. (d) Coronal targeted MIP image obtained at the origin of the renal arteries shows the relationship between the main renal arteries (curved arrows) and accessory renal arteries (straight arrows) and the lumber arteries (arrowhead). (e) Axial reformatted image clearly shows the main renal arteries (curved arrow) and accessory renal arteries (straight arrow) originating from the aorta. (f) Axial reformatted image obtained at a different level clearly shows the relationship between the renal artery (curved arrow) and the lumber artery (arrowhead).

View larger version (128K): [in a new window]   Figure 3c.  Postprocessing of an MR angiography data set from a living kidney donor. (a) Coronal full maximum intensity projection (MIP) image shows the aorta and its tributaries, including the main renal arteries (curved arrows), accessory renal arteries (straight arrows), and lumber arteries (arrowhead). (b) Coronal oblique linear reformatted image angled along the approximate course of the right renal vessels shows the main renal artery (curved arrow) and accessory renal artery (straight arrow) more clearly. (c) Coronal oblique linear reformatted image angled along the course of the left renal vessels shows the main renal artery (curved arrow), accessory renal artery (straight arrow), and lumber artery (arrowhead) more clearly. (d) Coronal targeted MIP image obtained at the origin of the renal arteries shows the relationship between the main renal arteries (curved arrows) and accessory renal arteries (straight arrows) and the lumber arteries (arrowhead). (e) Axial reformatted image clearly shows the main renal arteries (curved arrow) and accessory renal arteries (straight arrow) originating from the aorta. (f) Axial reformatted image obtained at a different level clearly shows the relationship between the renal artery (curved arrow) and the lumber artery (arrowhead).

View larger version (125K): [in a new window]   Figure 3d.  Postprocessing of an MR angiography data set from a living kidney donor. (a) Coronal full maximum intensity projection (MIP) image shows the aorta and its tributaries, including the main renal arteries (curved arrows), accessory renal arteries (straight arrows), and lumber arteries (arrowhead). (b) Coronal oblique linear reformatted image angled along the approximate course of the right renal vessels shows the main renal artery (curved arrow) and accessory renal artery (straight arrow) more clearly. (c) Coronal oblique linear reformatted image angled along the course of the left renal vessels shows the main renal artery (curved arrow), accessory renal artery (straight arrow), and lumber artery (arrowhead) more clearly. (d) Coronal targeted MIP image obtained at the origin of the renal arteries shows the relationship between the main renal arteries (curved arrows) and accessory renal arteries (straight arrows) and the lumber arteries (arrowhead). (e) Axial reformatted image clearly shows the main renal arteries (curved arrow) and accessory renal arteries (straight arrow) originating from the aorta. (f) Axial reformatted image obtained at a different level clearly shows the relationship between the renal artery (curved arrow) and the lumber artery (arrowhead).

View larger version (99K): [in a new window]   Figure 3e.  Postprocessing of an MR angiography data set from a living kidney donor. (a) Coronal full maximum intensity projection (MIP) image shows the aorta and its tributaries, including the main renal arteries (curved arrows), accessory renal arteries (straight arrows), and lumber arteries (arrowhead). (b) Coronal oblique linear reformatted image angled along the approximate course of the right renal vessels shows the main renal artery (curved arrow) and accessory renal artery (straight arrow) more clearly. (c) Coronal oblique linear reformatted image angled along the course of the left renal vessels shows the main renal artery (curved arrow), accessory renal artery (straight arrow), and lumber artery (arrowhead) more clearly. (d) Coronal targeted MIP image obtained at the origin of the renal arteries shows the relationship between the main renal arteries (curved arrows) and accessory renal arteries (straight arrows) and the lumber arteries (arrowhead). (e) Axial reformatted image clearly shows the main renal arteries (curved arrow) and accessory renal arteries (straight arrow) originating from the aorta. (f) Axial reformatted image obtained at a different level clearly shows the relationship between the renal artery (curved arrow) and the lumber artery (arrowhead).

View larger version (101K): [in a new window]   Figure 3f.  Postprocessing of an MR angiography data set from a living kidney donor. (a) Coronal full maximum intensity projection (MIP) image shows the aorta and its tributaries, including the main renal arteries (curved arrows), accessory renal arteries (straight arrows), and lumber arteries (arrowhead). (b) Coronal oblique linear reformatted image angled along the approximate course of the right renal vessels shows the main renal artery (curved arrow) and accessory renal artery (straight arrow) more clearly. (c) Coronal oblique linear reformatted image angled along the course of the left renal vessels shows the main renal artery (curved arrow), accessory renal artery (straight arrow), and lumber artery (arrowhead) more clearly. (d) Coronal targeted MIP image obtained at the origin of the renal arteries shows the relationship between the main renal arteries (curved arrows) and accessory renal arteries (straight arrows) and the lumber arteries (arrowhead). (e) Axial reformatted image clearly shows the main renal arteries (curved arrow) and accessory renal arteries (straight arrow) originating from the aorta. (f) Axial reformatted image obtained at a different level clearly shows the relationship between the renal artery (curved arrow) and the lumber artery (arrowhead).

View larger version (94K): [in a new window]   Figure 4a.  Laparoscopic nephrectomy on the right side. Cephalad = cephalic aspect of the patient. (a) Photograph shows that two renal arteries (arrows) have been identified. The kidney () is still in situ, whereas the liver (arrowhead) has been pushed away slightly for better access to the kidney and its vessels. The left side of the patient is contiguous to the operating table. This position provides the surgeon with full access to the right flank. (b) Photograph shows that one renal vein (arrow) has been identified. The kidney () has been mobilized after dissection from the Gerota fascia and has been flipped over to the left side of the patient for better visualization of the renal vessels. Arrowhead = liver.

View larger version (100K): [in a new window]   Figure 4b.  Laparoscopic nephrectomy on the right side. Cephalad = cephalic aspect of the patient. (a) Photograph shows that two renal arteries (arrows) have been identified. The kidney () is still in situ, whereas the liver (arrowhead) has been pushed away slightly for better access to the kidney and its vessels. The left side of the patient is contiguous to the operating table. This position provides the surgeon with full access to the right flank. (b) Photograph shows that one renal vein (arrow) has been identified. The kidney () has been mobilized after dissection from the Gerota fascia and has been flipped over to the left side of the patient for better visualization of the renal vessels. Arrowhead = liver.

View larger version (114K): [in a new window]   Figure 5a.  Single renal artery and renal vein bilaterally with DSA-MR angiographic correlation. (a) DSA image shows the abdominal aorta and its tributaries, including the renal arteries (straight arrows). Note the branching of the left renal artery (curved arrows). (b) Coronal oblique reformatted image from the MR angiography data set shows one artery on the right side (straight arrow), one renal vein (curved arrow), and the enhanced renal pelvis (top arrowhead) with the proximal ureter (bottom arrowhead). (c) Coronal oblique reformatted image of the left side shows one renal artery (straight arrow) with branching (curved arrows). Note that the smaller intrarenal vessels are not seen on the MR angiograms (b, c), in contrast to the DSA image (a).

View larger version (134K): [in a new window]   Figure 5b.  Single renal artery and renal vein bilaterally with DSA-MR angiographic correlation. (a) DSA image shows the abdominal aorta and its tributaries, including the renal arteries (straight arrows). Note the branching of the left renal artery (curved arrows). (b) Coronal oblique reformatted image from the MR angiography data set shows one artery on the right side (straight arrow), one renal vein (curved arrow), and the enhanced renal pelvis (top arrowhead) with the proximal ureter (bottom arrowhead). (c) Coronal oblique reformatted image of the left side shows one renal artery (straight arrow) with branching (curved arrows). Note that the smaller intrarenal vessels are not seen on the MR angiograms (b, c), in contrast to the DSA image (a).

View larger version (153K): [in a new window]   Figure 5c.  Single renal artery and renal vein bilaterally with DSA-MR angiographic correlation. (a) DSA image shows the abdominal aorta and its tributaries, including the renal arteries (straight arrows). Note the branching of the left renal artery (curved arrows). (b) Coronal oblique reformatted image from the MR angiography data set shows one artery on the right side (straight arrow), one renal vein (curved arrow), and the enhanced renal pelvis (top arrowhead) with the proximal ureter (bottom arrowhead). (c) Coronal oblique reformatted image of the left side shows one renal artery (straight arrow) with branching (curved arrows). Note that the smaller intrarenal vessels are not seen on the MR angiograms (b, c), in contrast to the DSA image (a).

View larger version (149K): [in a new window]   Figure 6a.  Early branching of the right renal artery and two right renal veins with DSA-MR angiographic correlation. (a) DSA image shows the abdominal aorta and its tributaries, including the right renal artery (arrow). (b) Selective DSA image of the right renal artery shows the main artery (straight arrow) and the first large branch (curved arrow), as well as some additional smaller branches distally. (c) Selective DSA image of the right kidney obtained during the venous phase shows slight enhancement of a large renal vein (arrow) and a small renal vein (arrowhead). (d) Coronal full MIP image from the MR angiography data set shows the aorta and its tributaries, including the right renal artery (arrow). Note the slight enhancement of the renal veins and part of the IVC (arrowhead) in this phase. (e) Coronal oblique reformatted image from the MR angiography data set shows the main right renal artery (straight arrow) and the first large branch (curved arrow). More distal smaller branches are not well visualized. The anatomic course of the IVC is indicated by a rectangular overlay (arrowheads). On the basis of the imaging findings, there seems to be sufficient distance between the origin of the renal artery and its first branch (about 2 cm). Therefore, the radiology report may suggest one renal artery on the right side. However, as the IVC runs anterior to the renal artery, the surgeon will not have access to the proximal part of the artery; therefore, from the surgical perspective, three arteries are present on the right. (f) Coronal oblique reformatted image of the venous phase clearly shows the large (straight arrow) and small (arrowhead) right renal veins originating from the IVC. Note also the homogeneous enhancement of the kidney () and the renal pelvis and proximal ureter (curved arrow).

View larger version (112K): [in a new window]   Figure 6b.  Early branching of the right renal artery and two right renal veins with DSA-MR angiographic correlation. (a) DSA image shows the abdominal aorta and its tributaries, including the right renal artery (arrow). (b) Selective DSA image of the right renal artery shows the main artery (straight arrow) and the first large branch (curved arrow), as well as some additional smaller branches distally. (c) Selective DSA image of the right kidney obtained during the venous phase shows slight enhancement of a large renal vein (arrow) and a small renal vein (arrowhead). (d) Coronal full MIP image from the MR angiography data set shows the aorta and its tributaries, including the right renal artery (arrow). Note the slight enhancement of the renal veins and part of the IVC (arrowhead) in this phase. (e) Coronal oblique reformatted image from the MR angiography data set shows the main right renal artery (straight arrow) and the first large branch (curved arrow). More distal smaller branches are not well visualized. The anatomic course of the IVC is indicated by a rectangular overlay (arrowheads). On the basis of the imaging findings, there seems to be sufficient distance between the origin of the renal artery and its first branch (about 2 cm). Therefore, the radiology report may suggest one renal artery on the right side. However, as the IVC runs anterior to the renal artery, the surgeon will not have access to the proximal part of the artery; therefore, from the surgical perspective, three arteries are present on the right. (f) Coronal oblique reformatted image of the venous phase clearly shows the large (straight arrow) and small (arrowhead) right renal veins originating from the IVC. Note also the homogeneous enhancement of the kidney () and the renal pelvis and proximal ureter (curved arrow).

View larger version (118K): [in a new window]   Figure 6c.  Early branching of the right renal artery and two right renal veins with DSA-MR angiographic correlation. (a) DSA image shows the abdominal aorta and its tributaries, including the right renal artery (arrow). (b) Selective DSA image of the right renal artery shows the main artery (straight arrow) and the first large branch (curved arrow), as well as some additional smaller branches distally. (c) Selective DSA image of the right kidney obtained during the venous phase shows slight enhancement of a large renal vein (arrow) and a small renal vein (arrowhead). (d) Coronal full MIP image from the MR angiography data set shows the aorta and its tributaries, including the right renal artery (arrow). Note the slight enhancement of the renal veins and part of the IVC (arrowhead) in this phase. (e) Coronal oblique reformatted image from the MR angiography data set shows the main right renal artery (straight arrow) and the first large branch (curved arrow). More distal smaller branches are not well visualized. The anatomic course of the IVC is indicated by a rectangular overlay (arrowheads). On the basis of the imaging findings, there seems to be sufficient distance between the origin of the renal artery and its first branch (about 2 cm). Therefore, the radiology report may suggest one renal artery on the right side. However, as the IVC runs anterior to the renal artery, the surgeon will not have access to the proximal part of the artery; therefore, from the surgical perspective, three arteries are present on the right. (f) Coronal oblique reformatted image of the venous phase clearly shows the large (straight arrow) and small (arrowhead) right renal veins originating from the IVC. Note also the homogeneous enhancement of the kidney () and the renal pelvis and proximal ureter (curved arrow).

View larger version (149K): [in a new window]   Figure 6d.  Early branching of the right renal artery and two right renal veins with DSA-MR angiographic correlation. (a) DSA image shows the abdominal aorta and its tributaries, including the right renal artery (arrow). (b) Selective DSA image of the right renal artery shows the main artery (straight arrow) and the first large branch (curved arrow), as well as some additional smaller branches distally. (c) Selective DSA image of the right kidney obtained during the venous phase shows slight enhancement of a large renal vein (arrow) and a small renal vein (arrowhead). (d) Coronal full MIP image from the MR angiography data set shows the aorta and its tributaries, including the right renal artery (arrow). Note the slight enhancement of the renal veins and part of the IVC (arrowhead) in this phase. (e) Coronal oblique reformatted image from the MR angiography data set shows the main right renal artery (straight arrow) and the first large branch (curved arrow). More distal smaller branches are not well visualized. The anatomic course of the IVC is indicated by a rectangular overlay (arrowheads). On the basis of the imaging findings, there seems to be sufficient distance between the origin of the renal artery and its first branch (about 2 cm). Therefore, the radiology report may suggest one renal artery on the right side. However, as the IVC runs anterior to the renal artery, the surgeon will not have access to the proximal part of the artery; therefore, from the surgical perspective, three arteries are present on the right. (f) Coronal oblique reformatted image of the venous phase clearly shows the large (straight arrow) and small (arrowhead) right renal veins originating from the IVC. Note also the homogeneous enhancement of the kidney () and the renal pelvis and proximal ureter (curved arrow).

View larger version (132K): [in a new window]   Figure 6e.  Early branching of the right renal artery and two right renal veins with DSA-MR angiographic correlation. (a) DSA image shows the abdominal aorta and its tributaries, including the right renal artery (arrow). (b) Selective DSA image of the right renal artery shows the main artery (straight arrow) and the first large branch (curved arrow), as well as some additional smaller branches distally. (c) Selective DSA image of the right kidney obtained during the venous phase shows slight enhancement of a large renal vein (arrow) and a small renal vein (arrowhead). (d) Coronal full MIP image from the MR angiography data set shows the aorta and its tributaries, including the right renal artery (arrow). Note the slight enhancement of the renal veins and part of the IVC (arrowhead) in this phase. (e) Coronal oblique reformatted image from the MR angiography data set shows the main right renal artery (straight arrow) and the first large branch (curved arrow). More distal smaller branches are not well visualized. The anatomic course of the IVC is indicated by a rectangular overlay (arrowheads). On the basis of the imaging findings, there seems to be sufficient distance between the origin of the renal artery and its first branch (about 2 cm). Therefore, the radiology report may suggest one renal artery on the right side. However, as the IVC runs anterior to the renal artery, the surgeon will not have access to the proximal part of the artery; therefore, from the surgical perspective, three arteries are present on the right. (f) Coronal oblique reformatted image of the venous phase clearly shows the large (straight arrow) and small (arrowhead) right renal veins originating from the IVC. Note also the homogeneous enhancement of the kidney () and the renal pelvis and proximal ureter (curved arrow).

View larger version (101K): [in a new window]   Figure 6f.  Early branching of the right renal artery and two right renal veins with DSA-MR angiographic correlation. (a) DSA image shows the abdominal aorta and its tributaries, including the right renal artery (arrow). (b) Selective DSA image of the right renal artery shows the main artery (straight arrow) and the first large branch (curved arrow), as well as some additional smaller branches distally. (c) Selective DSA image of the right kidney obtained during the venous phase shows slight enhancement of a large renal vein (arrow) and a small renal vein (arrowhead). (d) Coronal full MIP image from the MR angiography data set shows the aorta and its tributaries, including the right renal artery (arrow). Note the slight enhancement of the renal veins and part of the IVC (arrowhead) in this phase. (e) Coronal oblique reformatted image from the MR angiography data set shows the main right renal artery (straight arrow) and the first large branch (curved arrow). More distal smaller branches are not well visualized. The anatomic course of the IVC is indicated by a rectangular overlay (arrowheads). On the basis of the imaging findings, there seems to be sufficient distance between the origin of the renal artery and its first branch (about 2 cm). Therefore, the radiology report may suggest one renal artery on the right side. However, as the IVC runs anterior to the renal artery, the surgeon will not have access to the proximal part of the artery; therefore, from the surgical perspective, three arteries are present on the right. (f) Coronal oblique reformatted image of the venous phase clearly shows the large (straight arrow) and small (arrowhead) right renal veins originating from the IVC. Note also the homogeneous enhancement of the kidney () and the renal pelvis and proximal ureter (curved arrow).

View larger version (143K): [in a new window]   Figure 7a.  Relationship between the renal arteries, IVC, renal veins, and collecting systems. (a) Coronal full MIP image from the MR angiography data set shows one renal artery on the left side (top straight arrow) and branching of the right renal artery (bottom straight arrow) into three tributaries (arrowheads). Note the lumber artery (curved arrow). (b) Coronal targeted MIP image of the venous phase shows the complex relationship between the renal arteries (straight arrows), renal veins (curved arrows), and collecting systems (arrowheads). Note that the IVC is anterior to the right renal artery; thus, the IVC covers the origin of this artery as well as the proximal parts of its branches (which are shown in a). Note also that the renal vein on the left side (dotted lines) is much longer than that on the right. (c) Coronal targeted MIP image of the venous phase obtained slightly posterior clearly shows the collecting systems, including the renal pelves (arrowheads) and proximal ureters (arrows). At this level, the vertebrae (V) with their vessels are visible.

View larger version (151K): [in a new window]   Figure 7b.  Relationship between the renal arteries, IVC, renal veins, and collecting systems. (a) Coronal full MIP image from the MR angiography data set shows one renal artery on the left side (top straight arrow) and branching of the right renal artery (bottom straight arrow) into three tributaries (arrowheads). Note the lumber artery (curved arrow). (b) Coronal targeted MIP image of the venous phase shows the complex relationship between the renal arteries (straight arrows), renal veins (curved arrows), and collecting systems (arrowheads). Note that the IVC is anterior to the right renal artery; thus, the IVC covers the origin of this artery as well as the proximal parts of its branches (which are shown in a). Note also that the renal vein on the left side (dotted lines) is much longer than that on the right. (c) Coronal targeted MIP image of the venous phase obtained slightly posterior clearly shows the collecting systems, including the renal pelves (arrowheads) and proximal ureters (arrows). At this level, the vertebrae (V) with their vessels are visible.

View larger version (144K): [in a new window]   Figure 7c.  Relationship between the renal arteries, IVC, renal veins, and collecting systems. (a) Coronal full MIP image from the MR angiography data set shows one renal artery on the left side (top straight arrow) and branching of the right renal artery (bottom straight arrow) into three tributaries (arrowheads). Note the lumber artery (curved arrow). (b) Coronal targeted MIP image of the venous phase shows the complex relationship between the renal arteries (straight arrows), renal veins (curved arrows), and collecting systems (arrowheads). Note that the IVC is anterior to the right renal artery; thus, the IVC covers the origin of this artery as well as the proximal parts of its branches (which are shown in a). Note also that the renal vein on the left side (dotted lines) is much longer than that on the right. (c) Coronal targeted MIP image of the venous phase obtained slightly posterior clearly shows the collecting systems, including the renal pelves (arrowheads) and proximal ureters (arrows). At this level, the vertebrae (V) with their vessels are visible.

View larger version (126K): [in a new window]   Figure 8a.  Two renal arteries bilaterally with DSA-MR angiographic correlation. (a) DSA image shows two renal arteries on the left side (straight arrows) and two renal arteries on the right (arrowheads). Curved arrow = superior mesenteric artery. (b) Coronal full MIP image from the MR angiography data set obtained with a slight rotation to the right shows the right renal arteries (arrowheads) with overprojection of the superior mesenteric artery (curved arrow). Conversely, on the left side, the entire course of both arteries (straight arrows) can be seen without overprojection. (c) Coronal oblique reformatted image from the MR angiography data set obtained parallel to the course of the right renal vessels clearly shows the renal arteries (arrowheads) originating from the aorta and entering the right kidney. On the left side, the origins of both renal arteries are visible (arrows).

View larger version (126K): [in a new window]   Figure 8b.  Two renal arteries bilaterally with DSA-MR angiographic correlation. (a) DSA image shows two renal arteries on the left side (straight arrows) and two renal arteries on the right (arrowheads). Curved arrow = superior mesenteric artery. (b) Coronal full MIP image from the MR angiography data set obtained with a slight rotation to the right shows the right renal arteries (arrowheads) with overprojection of the superior mesenteric artery (curved arrow). Conversely, on the left side, the entire course of both arteries (straight arrows) can be seen without overprojection. (c) Coronal oblique reformatted image from the MR angiography data set obtained parallel to the course of the right renal vessels clearly shows the renal arteries (arrowheads) originating from the aorta and entering the right kidney. On the left side, the origins of both renal arteries are visible (arrows).

View larger version (156K): [in a new window]   Figure 8c.  Two renal arteries bilaterally with DSA-MR angiographic correlation. (a) DSA image shows two renal arteries on the left side (straight arrows) and two renal arteries on the right (arrowheads). Curved arrow = superior mesenteric artery. (b) Coronal full MIP image from the MR angiography data set obtained with a slight rotation to the right shows the right renal arteries (arrowheads) with overprojection of the superior mesenteric artery (curved arrow). Conversely, on the left side, the entire course of both arteries (straight arrows) can be seen without overprojection. (c) Coronal oblique reformatted image from the MR angiography data set obtained parallel to the course of the right renal vessels clearly shows the renal arteries (arrowheads) originating from the aorta and entering the right kidney. On the left side, the origins of both renal arteries are visible (arrows).

View larger version (114K): [in a new window]   Figure 9a.  Circumaortic left renal vein. (a) Coronal full MIP image from the MR angiography data set shows one renal artery bilaterally (arrows). (b) Coronal targeted MIP image of the venous phase shows the superior leg of a circumaortic left renal vein (curved arrow) draining into the IVC (straight arrow). (c) Coronal targeted MIP image of the venous phase obtained slightly posterior shows the inferior leg of the circumaortic renal vein (curved arrow) draining into the IVC (straight arrow). (d) Axial delayed gadolinium-enhanced 3D fast GRE image obtained with fat saturation at the level of the midpoles of the kidneys (arrowheads) shows the superior leg of the circumaortic renal vein (curved arrow) draining into the IVC (straight arrow). (e) Axial delayed gadolinium-enhanced 3D fast GRE image obtained with fat saturation at the level of the lower poles of the kidneys (arrowheads) shows the inferior leg of the circumaortic renal vein (curved arrow) crossing behind the aorta and draining into the IVC (straight arrow). (f) Axial single-shot fast SE image obtained at the level of the lower poles of the kidneys (arrowheads) shows the inferior leg of the circumaortic renal vein (curved arrow), which appears as an area of signal void, crossing behind the aorta and draining into the IVC (straight arrow).

View larger version (143K): [in a new window]   Figure 9b.  Circumaortic left renal vein. (a) Coronal full MIP image from the MR angiography data set shows one renal artery bilaterally (arrows). (b) Coronal targeted MIP image of the venous phase shows the superior leg of a circumaortic left renal vein (curved arrow) draining into the IVC (straight arrow). (c) Coronal targeted MIP image of the venous phase obtained slightly posterior shows the inferior leg of the circumaortic renal vein (curved arrow) draining into the IVC (straight arrow). (d) Axial delayed gadolinium-enhanced 3D fast GRE image obtained with fat saturation at the level of the midpoles of the kidneys (arrowheads) shows the superior leg of the circumaortic renal vein (curved arrow) draining into the IVC (straight arrow). (e) Axial delayed gadolinium-enhanced 3D fast GRE image obtained with fat saturation at the level of the lower poles of the kidneys (arrowheads) shows the inferior leg of the circumaortic renal vein (curved arrow) crossing behind the aorta and draining into the IVC (straight arrow). (f) Axial single-shot fast SE image obtained at the level of the lower poles of the kidneys (arrowheads) shows the inferior leg of the circumaortic renal vein (curved arrow), which appears as an area of signal void, crossing behind the aorta and draining into the IVC (straight arrow).

View larger version (151K): [in a new window]   Figure 9c.  Circumaortic left renal vein. (a) Coronal full MIP image from the MR angiography data set shows one renal artery bilaterally (arrows). (b) Coronal targeted MIP image of the venous phase shows the superior leg of a circumaortic left renal vein (curved arrow) draining into the IVC (straight arrow). (c) Coronal targeted MIP image of the venous phase obtained slightly posterior shows the inferior leg of the circumaortic renal vein (curved arrow) draining into the IVC (straight arrow). (d) Axial delayed gadolinium-enhanced 3D fast GRE image obtained with fat saturation at the level of the midpoles of the kidneys (arrowheads) shows the superior leg of the circumaortic renal vein (curved arrow) draining into the IVC (straight arrow). (e) Axial delayed gadolinium-enhanced 3D fast GRE image obtained with fat saturation at the level of the lower poles of the kidneys (arrowheads) shows the inferior leg of the circumaortic renal vein (curved arrow) crossing behind the aorta and draining into the IVC (straight arrow). (f) Axial single-shot fast SE image obtained at the level of the lower poles of the kidneys (arrowheads) shows the inferior leg of the circumaortic renal vein (curved arrow), which appears as an area of signal void, crossing behind the aorta and draining into the IVC (straight arrow).

View larger version (140K): [in a new window]   Figure 9d.  Circumaortic left renal vein. (a) Coronal full MIP image from the MR angiography data set shows one renal artery bilaterally (arrows). (b) Coronal targeted MIP image of the venous phase shows the superior leg of a circumaortic left renal vein (curved arrow) draining into the IVC (straight arrow). (c) Coronal targeted MIP image of the venous phase obtained slightly posterior shows the inferior leg of the circumaortic renal vein (curved arrow) draining into the IVC (straight arrow). (d) Axial delayed gadolinium-enhanced 3D fast GRE image obtained with fat saturation at the level of the midpoles of the kidneys (arrowheads) shows the superior leg of the circumaortic renal vein (curved arrow) draining into the IVC (straight arrow). (e) Axial delayed gadolinium-enhanced 3D fast GRE image obtained with fat saturation at the level of the lower poles of the kidneys (arrowheads) shows the inferior leg of the circumaortic renal vein (curved arrow) crossing behind the aorta and draining into the IVC (straight arrow). (f) Axial single-shot fast SE image obtained at the level of the lower poles of the kidneys (arrowheads) shows the inferior leg of the circumaortic renal vein (curved arrow), which appears as an area of signal void, crossing behind the aorta and draining into the IVC (straight arrow).

View larger version (123K): [in a new window]   Figure 9e.  Circumaortic left renal vein. (a) Coronal full MIP image from the MR angiography data set shows one renal artery bilaterally (arrows). (b) Coronal targeted MIP image of the venous phase shows the superior leg of a circumaortic left renal vein (curved arrow) draining into the IVC (straight arrow). (c) Coronal targeted MIP image of the venous phase obtained slightly posterior shows the inferior leg of the circumaortic renal vein (curved arrow) draining into the IVC (straight arrow). (d) Axial delayed gadolinium-enhanced 3D fast GRE image obtained with fat saturation at the level of the midpoles of the kidneys (arrowheads) shows the superior leg of the circumaortic renal vein (curved arrow) draining into the IVC (straight arrow). (e) Axial delayed gadolinium-enhanced 3D fast GRE image obtained with fat saturation at the level of the lower poles of the kidneys (arrowheads) shows the inferior leg of the circumaortic renal vein (curved arrow) crossing behind the aorta and draining into the IVC (straight arrow). (f) Axial single-shot fast SE image obtained at the level of the lower poles of the kidneys (arrowheads) shows the inferior leg of the circumaortic renal vein (curved arrow), which appears as an area of signal void, crossing behind the aorta and draining into the IVC (straight arrow).

View larger version (109K): [in a new window]   Figure 9f.  Circumaortic left renal vein. (a) Coronal full MIP image from the MR angiography data set shows one renal artery bilaterally (arrows). (b) Coronal targeted MIP image of the venous phase shows the superior leg of a circumaortic left renal vein (curved arrow) draining into the IVC (straight arrow). (c) Coronal targeted MIP image of the venous phase obtained slightly posterior shows the inferior leg of the circumaortic renal vein (curved arrow) draining into the IVC (straight arrow). (d) Axial delayed gadolinium-enhanced 3D fast GRE image obtained with fat saturation at the level of the midpoles of the kidneys (arrowheads) shows the superior leg of the circumaortic renal vein (curved arrow) draining into the IVC (straight arrow). (e) Axial delayed gadolinium-enhanced 3D fast GRE image obtained with fat saturation at the level of the lower poles of the kidneys (arrowheads) shows the inferior leg of the circumaortic renal vein (curved arrow) crossing behind the aorta and draining into the IVC (straight arrow). (f) Axial single-shot fast SE image obtained at the level of the lower poles of the kidneys (arrowheads) shows the inferior leg of the circumaortic renal vein (curved arrow), which appears as an area of signal void, crossing behind the aorta and draining into the IVC (straight arrow).

View larger version (155K): [in a new window]   Figure 10a.  Intravenous urographic, US, and MR imaging findings in duplication of the right renal collecting system. (a) Intravenous urogram shows duplication of the right renal pelvis and proximal ureter (curved arrows). The distal right ureter is just visible as a single structure (straight arrow). The left collecting system is normal (arrowheads). (b) Longitudinal US image of the right kidney shows a parenchymal bridge that separates the medulla within a smaller upper pole (arrowhead) and larger lower pole (arrow), findings compatible with a duplicated collecting system. (c) Longitudinal US image of the left kidney shows a normal-sized kidney with a normal medullary region (arrow). (d) Coronal targeted MIP image from the MR angiography data set of the venous phase shows more clearly the duplication of the proximal collecting system on the right side (curved arrows) with a single ureter distally (straight arrow). The left collecting system is normal (arrowheads). (e) Coronal targeted MIP image of the venous phase obtained at the level of the medulla of the kidneys shows the relatively dysplastic upper pole (arrowhead) and larger lower pole (curved arrow) on the right side, whereas the left kidney is normal (straight arrow). (f) Coronal full MIP image of the arterial phase with some venous enhancement shows the relationship of the renal veins (curved arrows) to the gonadal vein on the left side (arrowhead) and the duplicated collecting system on the right (straight arrow).

View larger version (139K): [in a new window]   Figure 10b.  Intravenous urographic, US, and MR imaging findings in duplication of the right renal collecting system. (a) Intravenous urogram shows duplication of the right renal pelvis and proximal ureter (curved arrows). The distal right ureter is just visible as a single structure (straight arrow). The left collecting system is normal (arrowheads). (b) Longitudinal US image of the right kidney shows a parenchymal bridge that separates the medulla within a smaller upper pole (arrowhead) and larger lower pole (arrow), findings compatible with a duplicated collecting system. (c) Longitudinal US image of the left kidney shows a normal-sized kidney with a normal medullary region (arrow). (d) Coronal targeted MIP image from the MR angiography data set of the venous phase shows more clearly the duplication of the proximal collecting system on the right side (curved arrows) with a single ureter distally (straight arrow). The left collecting system is normal (arrowheads). (e) Coronal targeted MIP image of the venous phase obtained at the level of the medulla of the kidneys shows the relatively dysplastic upper pole (arrowhead) and larger lower pole (curved arrow) on the right side, whereas the left kidney is normal (straight arrow). (f) Coronal full MIP image of the arterial phase with some venous enhancement shows the relationship of the renal veins (curved arrows) to the gonadal vein on the left side (arrowhead) and the duplicated collecting system on the right (straight arrow).

View larger version (130K): [in a new window]   Figure 10c.  Intravenous urographic, US, and MR imaging findings in duplication of the right renal collecting system. (a) Intravenous urogram shows duplication of the right renal pelvis and proximal ureter (curved arrows). The distal right ureter is just visible as a single structure (straight arrow). The left collecting system is normal (arrowheads). (b) Longitudinal US image of the right kidney shows a parenchymal bridge that separates the medulla within a smaller upper pole (arrowhead) and larger lower pole (arrow), findings compatible with a duplicated collecting system. (c) Longitudinal US image of the left kidney shows a normal-sized kidney with a normal medullary region (arrow). (d) Coronal targeted MIP image from the MR angiography data set of the venous phase shows more clearly the duplication of the proximal collecting system on the right side (curved arrows) with a single ureter distally (straight arrow). The left collecting system is normal (arrowheads). (e) Coronal targeted MIP image of the venous phase obtained at the level of the medulla of the kidneys shows the relatively dysplastic upper pole (arrowhead) and larger lower pole (curved arrow) on the right side, whereas the left kidney is normal (straight arrow). (f) Coronal full MIP image of the arterial phase with some venous enhancement shows the relationship of the renal veins (curved arrows) to the gonadal vein on the left side (arrowhead) and the duplicated collecting system on the right (straight arrow).

View larger version (165K): [in a new window]   Figure 10d.  Intravenous urographic, US, and MR imaging findings in duplication of the right renal collecting system. (a) Intravenous urogram shows duplication of the right renal pelvis and proximal ureter (curved arrows). The distal right ureter is just visible as a single structure (straight arrow). The left collecting system is normal (arrowheads). (b) Longitudinal US image of the right kidney shows a parenchymal bridge that separates the medulla within a smaller upper pole (arrowhead) and larger lower pole (arrow), findings compatible with a duplicated collecting system. (c) Longitudinal US image of the left kidney shows a normal-sized kidney with a normal medullary region (arrow). (d) Coronal targeted MIP image from the MR angiography data set of the venous phase shows more clearly the duplication of the proximal collecting system on the right side (curved arrows) with a single ureter distally (straight arrow). The left collecting system is normal (arrowheads). (e) Coronal targeted MIP image of the venous phase obtained at the level of the medulla of the kidneys shows the relatively dysplastic upper pole (arrowhead) and larger lower pole (curved arrow) on the right side, whereas the left kidney is normal (straight arrow). (f) Coronal full MIP image of the arterial phase with some venous enhancement shows the relationship of the renal veins (curved arrows) to the gonadal vein on the left side (arrowhead) and the duplicated collecting system on the right (straight arrow).

View larger version (153K): [in a new window]   Figure 10e.  Intravenous urographic, US, and MR imaging findings in duplication of the right renal collecting system. (a) Intravenous urogram shows duplication of the right renal pelvis and proximal ureter (curved arrows). The distal right ureter is just visible as a single structure (straight arrow). The left collecting system is normal (arrowheads). (b) Longitudinal US image of the right kidney shows a parenchymal bridge that separates the medulla within a smaller upper pole (arrowhead) and larger lower pole (arrow), findings compatible with a duplicated collecting system. (c) Longitudinal US image of the left kidney shows a normal-sized kidney with a normal medullary region (arrow). (d) Coronal targeted MIP image from the MR angiography data set of the venous phase shows more clearly the duplication of the proximal collecting system on the right side (curved arrows) with a single ureter distally (straight arrow). The left collecting system is normal (arrowheads). (e) Coronal targeted MIP image of the venous phase obtained at the level of the medulla of the kidneys shows the relatively dysplastic upper pole (arrowhead) and larger lower pole (curved arrow) on the right side, whereas the left kidney is normal (straight arrow). (f) Coronal full MIP image of the arterial phase with some venous enhancement shows the relationship of the renal veins (curved arrows) to the gonadal vein on the left side (arrowhead) and the duplicated collecting system on the right (straight arrow).

View larger version (135K): [in a new window]   Figure 10f.  Intravenous urographic, US, and MR imaging findings in duplication of the right renal collecting system. (a) Intravenous urogram shows duplication of the right renal pelvis and proximal ureter (curved arrows). The distal right ureter is just visible as a single structure (straight arrow). The left collecting system is normal (arrowheads). (b) Longitudinal US image of the right kidney shows a parenchymal bridge that separates the medulla within a smaller upper pole (arrowhead) and larger lower pole (arrow), findings compatible with a duplicated collecting system. (c) Longitudinal US image of the left kidney shows a normal-sized kidney with a normal medullary region (arrow). (d) Coronal targeted MIP image from the MR angiography data set of the venous phase shows more clearly the duplication of the proximal collecting system on the right side (curved arrows) with a single ureter distally (straight arrow). The left collecting system is normal (arrowheads). (e) Coronal targeted MIP image of the venous phase obtained at the level of the medulla of the kidneys shows the relatively dysplastic upper pole (arrowhead) and larger lower pole (curved arrow) on the right side, whereas the left kidney is normal (straight arrow). (f) Coronal full MIP image of the arterial phase with some venous enhancement shows the relationship of the renal veins (curved arrows) to the gonadal vein on the left side (arrowhead) and the duplicated collecting system on the right (straight arrow).

View larger version (93K): [in a new window]   Figure 11a.  Renal cyst at US, MR imaging, and MR angiography. (a) Longitudinal US image shows the right kidney, which has a small cyst in the upper pole (arrow). (b) Coronal single-shot fast SE image shows the cyst as a hyperintense, sharply marginated lesion (arrow). (c) Axial T2-weighted fast SE image obtained with fat saturation also shows the cyst (arrow). (d) Coronal source image from the MR angiography data set does not show a well-circumscribed lesion. (e) Coronal source image from the MR venography data set shows the cyst clearly (arrow). (f) Axial delayed gadolinium-enhanced 3D fast GRE image obtained with fat saturation shows the cyst as a nonenhancing, sharply marginated structure (arrow). This sequence allows exclusion of any lesion with slowly enhancing solid components.

View larger version (114K): [in a new window]   Figure 11b.  Renal cyst at US, MR imaging, and MR angiography. (a) Longitudinal US image shows the right kidney, which has a small cyst in the upper pole (arrow). (b) Coronal single-shot fast SE image shows the cyst as a hyperintense, sharply marginated lesion (arrow). (c) Axial T2-weighted fast SE image obtained with fat saturation also shows the cyst (arrow). (d) Coronal source image from the MR angiography data set does not show a well-circumscribed lesion. (e) Coronal source image from the MR venography data set shows the cyst clearly (arrow). (f) Axial delayed gadolinium-enhanced 3D fast GRE image obtained with fat saturation shows the cyst as a nonenhancing, sharply marginated structure (arrow). This sequence allows exclusion of any lesion with slowly enhancing solid components.

View larger version (109K): [in a new window]   Figure 11c.  Renal cyst at US, MR imaging, and MR angiography. (a) Longitudinal US image shows the right kidney, which has a small cyst in the upper pole (arrow). (b) Coronal single-shot fast SE image shows the cyst as a hyperintense, sharply marginated lesion (arrow). (c) Axial T2-weighted fast SE image obtained with fat saturation also shows the cyst (arrow). (d) Coronal source image from the MR angiography data set does not show a well-circumscribed lesion. (e) Coronal source image from the MR venography data set shows the cyst clearly (arrow). (f) Axial delayed gadolinium-enhanced 3D fast GRE image obtained with fat saturation shows the cyst as a nonenhancing, sharply marginated structure (arrow). This sequence allows exclusion of any lesion with slowly enhancing solid components.

View larger version (114K): [in a new window]   Figure 11d.  Renal cyst at US, MR imaging, and MR angiography. (a) Longitudinal US image shows the right kidney, which has a small cyst in the upper pole (arrow). (b) Coronal single-shot fast SE image shows the cyst as a hyperintense, sharply marginated lesion (arrow). (c) Axial T2-weighted fast SE image obtained with fat saturation also shows the cyst (arrow). (d) Coronal source image from the MR angiography data set does not show a well-circumscribed lesion. (e) Coronal source image from the MR venography data set shows the cyst clearly (arrow). (f) Axial delayed gadolinium-enhanced 3D fast GRE image obtained with fat saturation shows the cyst as a nonenhancing, sharply marginated structure (arrow). This sequence allows exclusion of any lesion with slowly enhancing solid components.

View larger version (122K): [in a new window]   Figure 11e.  Renal cyst at US, MR imaging, and MR angiography. (a) Longitudinal US image shows the right kidney, which has a small cyst in the upper pole (arrow). (b) Coronal single-shot fast SE image shows the cyst as a hyperintense, sharply marginated lesion (arrow). (c) Axial T2-weighted fast SE image obtained with fat saturation also shows the cyst (arrow). (d) Coronal source image from the MR angiography data set does not show a well-circumscribed lesion. (e) Coronal source image from the MR venography data set shows the cyst clearly (arrow). (f) Axial delayed gadolinium-enhanced 3D fast GRE image obtai