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Nutcracker phenomenon
CASE REPORTS
NUTCRACKER
PHENOMENON
DAVID
I? DEVER,
M.D.
MARK
E. GINSBURG,
DAVID
J. MILLET,
M.D. M.D.
MICHAEL
J. FEINSTEIN,
ABRAHAM
T. K. COCKETT,
From the Departments University of Rochester
ABSTRACT-A case options are discussed.
of
the nutcracker
M.D. M.D.
of Urology, Surgery, School of Medicine,
phenomenon
The nutcracker phenomenon refers to compression of the left renal vein between the aorta and the superior mesenteric artery. It is an infrequently recognized entity which has been associated with hematuria, abdominal pain, and varicocele formation. 1-3 The case report illustrates the typical angiographic findings, and discusses the diagnosis and therapy of this disorder.
and Radiology, Rochester, New York
is reported.
The diagnostic
and therapeutic
Case Report A forty-year-old white woman presented to the urologist with gross painless hematuria. She denied any flank pain, dysuria, frequency, or previous trauma. She had previously undergone a tubal ligation and left oophorectomy. A urine culture was negative. Cystoscopy revealed bloody efflux from the left ureteral orifice. An
FIGURE 1. (A) Selective renal angiogram demonstrating reflux of contrast material into periureteral and gonadal veins. (B) Selective left renal venogram demonstrating extrinsic compression by superior mesenteric artery.
FIGURE 2. Comvosite recoflstruction illustratbg course of superior mesenteric artery and compression of left renal 11 vein. ’ _I ”
k
‘\
’
intravenous pyelogram (IVP) demonstrated left ureteral notching. A selective renal angiogram demonstrated reflux into periureteral and gonadal collateral vessels during the venous phase (Fig. 1A). There was no evidence of intrarenal pathology. Selective left renal vein catheterization was performed. The pull back pressure in the distal renal vein was 5 mm Hg and in the inferior vena cava (IVC) measured 2 mm Hg. Venography demonstrated extrinsic compression of the vein by the superior mesenteric artery (Figs. 1B and 2). The patient continues to have intermittent hematuria and a stable hematocrit, and she is being observed.
ter, the cause is thought to be a decrease in the angle of the superior mesenteric artery from the aortae4 This may also be true in the nutcracker phenomenon. Wendel, Crawford, and Helman however, have proposed that posterior renal ptosis with stretching of the left renal vein over the aorta may be a factor. It should be noted that simultaneous obstruction of the left renal vein and the duodenum by the superior mesenteric artery has been reported. The nutcracker syndrome has been associated with three important clinical sequelae: unilateral hematuria, the gonadal vein syndrome, and varicocele. Unilateral hematuria is a result of an abnormal communication between the submucosal venous plexus and the calyceal system presumably induced by venous hypertension.6 The gonadal vein syndrome, characterized by abdominal and flank pain exacerbated by sitting, standing, or walking, was reported in association with the nutcracker phenomenon in 21 patients by Coolsaet.2 Sixteen patients underwent operation, and 12 were found to have distinct periureteric varices. Finally, Zerhouni et al.’ reported the nutcracker phenomenon in 3 patients investigated for varicocele. A significant pressure gradient could be measured across the obstruction. No gradient w-as found in 5
Comment Anatomically the left renal vein crosses the midline in the fork formed by the aorta and the superior mesenteric artery. Compression of the vein between these two structures, termed the nutcracker phenomenon, may result in dilatation and incompetence of the venous collateral system draining the left kidney. This situation is analogous to the superior mesenteric artery syndrome in which compression of the duodenum between the superior mesenteric artery and the aorta results in duodenal obstruction. In the lat-
UROLOGY
/
JUNE
1986
/
VOLUME
XXVII,
NUMBER
6
541
normal subjects. They proposed that varicocele may be due to left renal vein compression and not due to incompetence of spermatic vein valves. The diagnosis is established by demonstrating compression of the left renal vein between the aorta and superior mesenteric artery during selective renal venography. In addition, a significant pressure gradient should exist across the obstruction. A gradient of less than 1 mm Hg between the distal left renal vein and the inferior vena cava was noted in 98 per cent of normal subjects studied by Beinart et aZ.’ The magnitude of the gradient will vary, however, reflecting not only the degree of obstruction, but also the extent of collateralization and level of hydration. In 1 patient the gradient was only 3 mm Hg. However, the patient was volume depleted as reflected by the IVC pressure of 2 mm Hg. In addition, adequate collateralization may have resulted in dissipation of pressure. Other studies may be helpful. The IVP may show ureteral notching by varicosities. Reversal of flow in the renal vein on arteriography is suggestive of obstruction but nonspecific, seen in 12 per cent of studies.6Enhanced computerized tomography (CT) scanning may show abnormal venous collaterals.e Therapy is dictated by the clinical situation. Mild hematuria is benign and can be observed. Massive hematuria and pain are indications for surgical intervention. Ligation and stripping of varicosities surrounding the ureter have been successful, but this fails to addressthe underlying pathology. Anterior nephropexy has been advocated5 where posterior renal ptosis is be-
lieved to contribute to renal vein obstruction. Nephrectomy is generally too radical for this benign condition. Coolsaetl” has advocated renal vein bypassto reduce the pressurein the collateral bed. Direct reimplantation of the renal vein in a more inferior location in the IVC has been reported by Stewart and Reiman.” This last approach appears logical for patients in whom a significant pressure gradient exists.
542
UROLOGY
Urology Associates of Rochester 220 Alexander Street Rochester, New York 14607 (DR. DEVER) References 1. Zerhouni EA, Siegelman SS, Walsh PC, and White RI: Elevated pressure in the left renal vein in patients with varicocele: preliminary observation, J Urol 123: 512 (1980). 2. Coolsaet B-LRA: Ureteric pathology in relation to left and right gonadal veins, Urology 12: 40 (1978). 3. Sarnellno W: Varices of ureter: rare cause of hematuria, J Urol 84: 55 (1965). 4. Choi SH, and Pfalzer F: Superior mesenteric artery syndrome, NY State J Med 76: 986 (1976). 5. Wendel RG, Crawford ED, and Helman KN: The nutcracker phenomenon: an unusual cause for renal varicosities with hematuria, J Urol 123: 761 (1980). 6. Lopatkin NA, Morozov AV, and Lopatkina LN: Essential renal haemorrhages, Eur Urol4: 115 (1978). 7. Beinart C, et al: Left renal vein to inferior vena cava pressure relationship in humans, J Urol 127: 1070 (1982). 8. Ahlberg NE: Right and left gonadal veins. An anatomical and statistical study, Acta Radio1 Diag 4: 593 (1966). 9. Weiner SN, Bernstein RG, Morehouse H, and Golden RA: Hematuria secondary to left peripelvic and gonadal vein varices, Urology 22: 81 (1983). 10. Coolsaet BLRA: Nutcracker phenomenon: an unusual cause for renal varicosities with hematuria (letter to the editor), J Urol 125: 134 (1981). 11. Stewart B, and Reiman G: Left renal venous hypertension “nutcracker” syndrome, Urology 20: 365 (1982).
/
JUNE
1986
/
VOLUME
XXVII,
NUMBER
6
NUTCRACKER
PHENOMENON
DAVID
I? DEVER,
M.D.
MARK
E. GINSBURG,
DAVID
J. MILLET,
M.D. M.D.
MICHAEL
J. FEINSTEIN,
ABRAHAM
T. K. COCKETT,
From the Departments University of Rochester
ABSTRACT-A case options are discussed.
of
the nutcracker
M.D. M.D.
of Urology, Surgery, School of Medicine,
phenomenon
The nutcracker phenomenon refers to compression of the left renal vein between the aorta and the superior mesenteric artery. It is an infrequently recognized entity which has been associated with hematuria, abdominal pain, and varicocele formation. 1-3 The case report illustrates the typical angiographic findings, and discusses the diagnosis and therapy of this disorder.
and Radiology, Rochester, New York
is reported.
The diagnostic
and therapeutic
Case Report A forty-year-old white woman presented to the urologist with gross painless hematuria. She denied any flank pain, dysuria, frequency, or previous trauma. She had previously undergone a tubal ligation and left oophorectomy. A urine culture was negative. Cystoscopy revealed bloody efflux from the left ureteral orifice. An
FIGURE 1. (A) Selective renal angiogram demonstrating reflux of contrast material into periureteral and gonadal veins. (B) Selective left renal venogram demonstrating extrinsic compression by superior mesenteric artery.
FIGURE 2. Comvosite recoflstruction illustratbg course of superior mesenteric artery and compression of left renal 11 vein. ’ _I ”
k
‘\
’
intravenous pyelogram (IVP) demonstrated left ureteral notching. A selective renal angiogram demonstrated reflux into periureteral and gonadal collateral vessels during the venous phase (Fig. 1A). There was no evidence of intrarenal pathology. Selective left renal vein catheterization was performed. The pull back pressure in the distal renal vein was 5 mm Hg and in the inferior vena cava (IVC) measured 2 mm Hg. Venography demonstrated extrinsic compression of the vein by the superior mesenteric artery (Figs. 1B and 2). The patient continues to have intermittent hematuria and a stable hematocrit, and she is being observed.
ter, the cause is thought to be a decrease in the angle of the superior mesenteric artery from the aortae4 This may also be true in the nutcracker phenomenon. Wendel, Crawford, and Helman however, have proposed that posterior renal ptosis with stretching of the left renal vein over the aorta may be a factor. It should be noted that simultaneous obstruction of the left renal vein and the duodenum by the superior mesenteric artery has been reported. The nutcracker syndrome has been associated with three important clinical sequelae: unilateral hematuria, the gonadal vein syndrome, and varicocele. Unilateral hematuria is a result of an abnormal communication between the submucosal venous plexus and the calyceal system presumably induced by venous hypertension.6 The gonadal vein syndrome, characterized by abdominal and flank pain exacerbated by sitting, standing, or walking, was reported in association with the nutcracker phenomenon in 21 patients by Coolsaet.2 Sixteen patients underwent operation, and 12 were found to have distinct periureteric varices. Finally, Zerhouni et al.’ reported the nutcracker phenomenon in 3 patients investigated for varicocele. A significant pressure gradient could be measured across the obstruction. No gradient w-as found in 5
Comment Anatomically the left renal vein crosses the midline in the fork formed by the aorta and the superior mesenteric artery. Compression of the vein between these two structures, termed the nutcracker phenomenon, may result in dilatation and incompetence of the venous collateral system draining the left kidney. This situation is analogous to the superior mesenteric artery syndrome in which compression of the duodenum between the superior mesenteric artery and the aorta results in duodenal obstruction. In the lat-
UROLOGY
/
JUNE
1986
/
VOLUME
XXVII,
NUMBER
6
541
normal subjects. They proposed that varicocele may be due to left renal vein compression and not due to incompetence of spermatic vein valves. The diagnosis is established by demonstrating compression of the left renal vein between the aorta and superior mesenteric artery during selective renal venography. In addition, a significant pressure gradient should exist across the obstruction. A gradient of less than 1 mm Hg between the distal left renal vein and the inferior vena cava was noted in 98 per cent of normal subjects studied by Beinart et aZ.’ The magnitude of the gradient will vary, however, reflecting not only the degree of obstruction, but also the extent of collateralization and level of hydration. In 1 patient the gradient was only 3 mm Hg. However, the patient was volume depleted as reflected by the IVC pressure of 2 mm Hg. In addition, adequate collateralization may have resulted in dissipation of pressure. Other studies may be helpful. The IVP may show ureteral notching by varicosities. Reversal of flow in the renal vein on arteriography is suggestive of obstruction but nonspecific, seen in 12 per cent of studies.6Enhanced computerized tomography (CT) scanning may show abnormal venous collaterals.e Therapy is dictated by the clinical situation. Mild hematuria is benign and can be observed. Massive hematuria and pain are indications for surgical intervention. Ligation and stripping of varicosities surrounding the ureter have been successful, but this fails to addressthe underlying pathology. Anterior nephropexy has been advocated5 where posterior renal ptosis is be-
lieved to contribute to renal vein obstruction. Nephrectomy is generally too radical for this benign condition. Coolsaetl” has advocated renal vein bypassto reduce the pressurein the collateral bed. Direct reimplantation of the renal vein in a more inferior location in the IVC has been reported by Stewart and Reiman.” This last approach appears logical for patients in whom a significant pressure gradient exists.
542
UROLOGY
Urology Associates of Rochester 220 Alexander Street Rochester, New York 14607 (DR. DEVER) References 1. Zerhouni EA, Siegelman SS, Walsh PC, and White RI: Elevated pressure in the left renal vein in patients with varicocele: preliminary observation, J Urol 123: 512 (1980). 2. Coolsaet B-LRA: Ureteric pathology in relation to left and right gonadal veins, Urology 12: 40 (1978). 3. Sarnellno W: Varices of ureter: rare cause of hematuria, J Urol 84: 55 (1965). 4. Choi SH, and Pfalzer F: Superior mesenteric artery syndrome, NY State J Med 76: 986 (1976). 5. Wendel RG, Crawford ED, and Helman KN: The nutcracker phenomenon: an unusual cause for renal varicosities with hematuria, J Urol 123: 761 (1980). 6. Lopatkin NA, Morozov AV, and Lopatkina LN: Essential renal haemorrhages, Eur Urol4: 115 (1978). 7. Beinart C, et al: Left renal vein to inferior vena cava pressure relationship in humans, J Urol 127: 1070 (1982). 8. Ahlberg NE: Right and left gonadal veins. An anatomical and statistical study, Acta Radio1 Diag 4: 593 (1966). 9. Weiner SN, Bernstein RG, Morehouse H, and Golden RA: Hematuria secondary to left peripelvic and gonadal vein varices, Urology 22: 81 (1983). 10. Coolsaet BLRA: Nutcracker phenomenon: an unusual cause for renal varicosities with hematuria (letter to the editor), J Urol 125: 134 (1981). 11. Stewart B, and Reiman G: Left renal venous hypertension “nutcracker” syndrome, Urology 20: 365 (1982).
/
JUNE
1986
/
VOLUME
XXVII,
NUMBER
6