Nutcracker Syndrome, clinically carectered by hematuria,
flank pain, left-sided varicocele or pelvic congestion, refers to
the compression of the left renal vein between the superior
mesenteric artery and the abdominal aorta. Though its incidence is quite prevalent through observing distended left renal vein
on ultrasonography and CT, asymtomatic nutcracker syndrome
presents large parts.
The diagnosis and the indication of Nutcracker Syndrome for
surgical treatment have not been unified during these years.
Recurrent gross hematuria, persittent orthostatic proteinuria
were taken into consideration largely in the surgical treatment
for Nutcracker Syndrome. Renal vein transposition, autotransplantation
and endovascular stents, three conventiaonal
options, have been associated with good outcomes and relatively
less morbidity, been performed through many countrys.
Extravascular stenting was used on the left renal vein to relieve
the outflow obstruction, attenuating symptoms of Nutcracker
syndrome, first reported in 1988, has been generalized due to
no theraputic coagulation needed postoperatively. To objective
application of extravascular stent for nuctcracker syndrome, also
to evaluate its safety and feasibility, we reviewed our experience
with extrovascular stenting for patients with Nutcracker
Diagnostic algorithm for Nutcracker Syndrome was as
follows: Patients with symptoms of gross hematuria, flank pain
or significent left side varicocele, were performed urine routine
test, urinary red cell morpholoogy. Patients with 80% isomorphic
red cells were acquired to measure the anteroposterior(AP)
diameter and peak velocity(PV) at the hilar portion of the LRV
and at the LRV between the aorta and the superior mesenteric
artery(SMA) through ultrasonography. Criterion of more than
5.0 for the ratio of AP diameter and the ratio of PV was suspected
for the nutcracker syndrome. Computerized angiographic
tomography of the abdomen was underwent to delineate the
anatomical relation of LRV with aorta and SMA for the suspects.
Through the diagnostic algorithm above, extrovascular
stenting for Nutcracker syndrome was done to 16 patients
with recurrent gross hematuria, 1 with persittent orthostatic
proteinuria from November 2009 to June 2011.
Under general anesthesia, patients were placed in the
right lateral decubitus position. Splenocolic ligament was
disconnected to expose renal pediclce. Splited the vagina
vasorum, ligated left adrenal vein and left gonadal vein routinely,
left renal vein was mobilized from renal hilus to inferior vena cave
finely. The diameter of LRV at the hilar protion was significent
larger than that at the position between the aortha and the SMA.
SMA was isolated with peripheral fibrous bundle and raised it,
the discontiuation of LRV would be attenuated quickly, which
represented the position of Nutcracker syndrome. Thinnd LRV
through clamping the hilar portion with rubber belt, if necessary
occluded left renal arteries. A reinforced polytetrafluoroethyline
graft was applied around the thinnd LRV, unclamp the belt around hilar portion of LRV, which length was fit for the entire
LRV to prevent displacement postoperatively.
Symptoms of Nutcracker syndrome, urinal routine test,
urinary red cell morphology and ultrasonography of all patients
were performed every 6 months after surgery. The follow up
period was 6 to 12 months.
5 patients (3 males, 2 females) underwent extravascular
stenting through open surgery, the remaining 11 (8 males, 3
females) did through laparoscopic extravascular stenting for
nutcarcker syndrome. 7 patients had recurrent gross hematuria,
more obvious after exercise. Five had symptoms of left flank pain
with associated hematuria, 4 male patients had gross hematuria
along with obvious left side varicocele. The duration of
symptoms ranged from 3 months to 2 years (mean 17.2 months).
The mean diameters of the hilar and aortomesenteric portions
of the LRV were 9.86 mm (range from 5.3 to 14.9 mm) and 2.17
mm (range from 1.0 to 3.0 mm), respectively.
Of the 16 patients, one was found to have chylous ascites,
a rare early postoperative complication. Re-exploration was
performed to ligate the lymphatic chammels. The remaining 15
patients significently attenuated symptoms of hematuia, gross
hematuria resolved in all patients, though 4 having microscopic
haematuria. Ultrasonography showed anteroposterior
diameter of LRV at the hilar portion and between the aorta
and the superior mesenteric artery were improved to 4.7-
6.5 mm( mean 5.4 mm) and 7.0-9.3 mm (mean 8.6 mm),
respectively, confirming no recompression of LRV between the
abdominal aorta and SMA. Simultaneously, 4 patients along
with preoperative left side varicocele were all seen to improve
significantly. There was no thrombosis happened despite no
therapeutic anticoagulation recommended during 2 years follow
Diagnosis of the nutcracker syndrome largely depends on the
symptom of haematuria, basic laboratory test results for excluding
other causes of haematuria, ultrasonography and computerized
angiographic tomography for view compression of LRV at the
position between the aortha and the SMA. Considering the
process needn't to transplant LRV or to insert entovascular stent,
extravascular stenting is a feasible, safe option for the nutcracker
syndrome. Patients of nutcracker syndrome having the only
symptom of significant varicocele are recommended for surgery
from our experience.