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Doppler Sonographic Indices in Diagnosing the Nutcracker Phenomenon in a Hematuric Adolescent
IMAGING
skin graft or progressive dilation, since most of their patients are adults and are ready to use the neovagina soon after construction. Douglas A. Canning, M.D.
IMAGING Doppler Sonographic Indices in Diagnosing the Nutcracker Phenomenon in a Hematuric Adolescent ¨ AND M. SEC ¸ IL, Division of Pediatric Nephrology and Radiology, Department S. KAVUKCU, B. KASAP, Y. GOKTAY of Pediatrics, Dokuz Eylu¨l University, School of Medicine, Izmir, Turkey J Clin Ultrasound, 32: 37– 41, 2004 Compression of the left renal vein between the aorta and the superior mesenteric artery, known as the nutcracker phenomenon, may cause gross or microscopic hematuria, pain in the flank, proteinuria, or a combination of these symptoms. We report the case of a hematuric adolescent diagnosed with a high index of suspicion by noninvasive Doppler sonography using the diagnostic indices of Doppler sonography established for adults with hematuria. Compression of the patient’s left renal vein at the aortomesenteric portion and dilatation at the hilar portion were visualized by magnetic resonance angiography, which verified the diagnosis. Editorial Comment: Occasionally, the left renal vein may be compressed between the aorta and superior mesenteric artery (SMA), leading to venous hypertension and formation of renal and ureteral varices. This condition may result in hematuria and is called the nutcracker syndrome. There are multiple causes of this syndrome. Most commonly it is due to abnormal branching of the SMA. The authors state that the normal branching of the SMA is near 90 degrees on a sagittal view (I know of no study recording the range of normal, and I happen to see a range of appearances). With the nutcracker phenomenon the superior mesenteric artery has a caudal position, allowing for the renal vein to be sandwiched between the SMA and the aorta. This narrow angle can decrease even further when the patient is in the upright position. Computerized tomography with 3-dimensional reconstruction and magnetic resonance imaging with 3-dimensional reconstruction can be used for diagnosis. Historically, renal venography was used for this diagnosis. Color Doppler ultrasound is an interesting option. Other authors have suggested a proximal renal vein size-to-distal renal vein size ratio of greater than 5 and a proximal renal vein peak systolic velocity-to-distal renal vein peak systolic velocity ratio of greater than 5 to make the diagnosis.1 Patients with hematuria and left flank pain may be evaluated for the nutcracker syndrome, especially when other causes are excluded. Computerized tomographic venography and magnetic resonance venography are valuable options. However, ultrasound is an additional consideration, especially in the patient who is slender or normal in body size. Cary Siegel, M.D. 1. Kim, S. W., Kim, H. D., Cho, H. D., Chung, J. W., Park, J. H. and Han, M. C.: Nutcracker syndrome: diagnosis with Doppler US. Radiology, 198: 93, 1996
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skin graft or progressive dilation, since most of their patients are adults and are ready to use the neovagina soon after construction. Douglas A. Canning, M.D.
IMAGING Doppler Sonographic Indices in Diagnosing the Nutcracker Phenomenon in a Hematuric Adolescent ¨ AND M. SEC ¸ IL, Division of Pediatric Nephrology and Radiology, Department S. KAVUKCU, B. KASAP, Y. GOKTAY of Pediatrics, Dokuz Eylu¨l University, School of Medicine, Izmir, Turkey J Clin Ultrasound, 32: 37– 41, 2004 Compression of the left renal vein between the aorta and the superior mesenteric artery, known as the nutcracker phenomenon, may cause gross or microscopic hematuria, pain in the flank, proteinuria, or a combination of these symptoms. We report the case of a hematuric adolescent diagnosed with a high index of suspicion by noninvasive Doppler sonography using the diagnostic indices of Doppler sonography established for adults with hematuria. Compression of the patient’s left renal vein at the aortomesenteric portion and dilatation at the hilar portion were visualized by magnetic resonance angiography, which verified the diagnosis. Editorial Comment: Occasionally, the left renal vein may be compressed between the aorta and superior mesenteric artery (SMA), leading to venous hypertension and formation of renal and ureteral varices. This condition may result in hematuria and is called the nutcracker syndrome. There are multiple causes of this syndrome. Most commonly it is due to abnormal branching of the SMA. The authors state that the normal branching of the SMA is near 90 degrees on a sagittal view (I know of no study recording the range of normal, and I happen to see a range of appearances). With the nutcracker phenomenon the superior mesenteric artery has a caudal position, allowing for the renal vein to be sandwiched between the SMA and the aorta. This narrow angle can decrease even further when the patient is in the upright position. Computerized tomography with 3-dimensional reconstruction and magnetic resonance imaging with 3-dimensional reconstruction can be used for diagnosis. Historically, renal venography was used for this diagnosis. Color Doppler ultrasound is an interesting option. Other authors have suggested a proximal renal vein size-to-distal renal vein size ratio of greater than 5 and a proximal renal vein peak systolic velocity-to-distal renal vein peak systolic velocity ratio of greater than 5 to make the diagnosis.1 Patients with hematuria and left flank pain may be evaluated for the nutcracker syndrome, especially when other causes are excluded. Computerized tomographic venography and magnetic resonance venography are valuable options. However, ultrasound is an additional consideration, especially in the patient who is slender or normal in body size. Cary Siegel, M.D. 1. Kim, S. W., Kim, H. D., Cho, H. D., Chung, J. W., Park, J. H. and Han, M. C.: Nutcracker syndrome: diagnosis with Doppler US. Radiology, 198: 93, 1996
311