Laparoscopic splenorenal venous bypass fornutcracker syndromeBenjamin I. Chung, MD, and Inderbir S. Gill, MD, Cleveland, Ohio

Nutcracker syndrome is a rare entity caused by extrinsic compression on the left renal vein as it crosses between thesuperior mesenteric artery and the aorta. It can clinically present with flank pain and hematuria. Accepted treatmentsinclude open vascular bypass procedures or endoluminal stenting. We present the first description, to our knowledge, ofa laparoscopic splenic vein–left renal vein bypass to relieve the outflow obstruction. The patient, a 29-year-old womanwith debilitating left flank pain, presented with nutcracker syndrome. Left renal vein outflow was obstructed at the levelof the intersection between the aorta and the superior mesenteric artery. The option of laparoscopic splenic to left renalvein bypass was discussed and performed. A five-port transperitoneal approach was used. Meticulous vascular control wasachieved with numerous laparoscopic vascular bulldog clamps. With completely intracorporeal suturing techniques, thesplenic vein was anastomosed to the superior aspect of the anterior left renal vein. Total warm ischemia time was 37minutes. The anastomosis was watertight immediately upon unclamping. Interestingly, upon unclamping, the luminaldiameter of the splenic vein appeared to increase to twice its native diameter. The proximal left renal vein appeared lessdistended, indicating preferential venous outflow through the newly created venous bypass. Blood loss was minimal, nointraoperative or postoperative complications occurred, and the patient’s symptoms improved. This report continues toaugment the indications for laparoscopic surgery in even complex, urologic vascular situations. ( J Vasc Surg 2009;49:

1319-23.)

Nutcracker syndrome is rare entity caused by extrinsiccompression of the left renal vein by the superior mesen-teric artery (SMA) as the vein crosses between it and theaorta. The resultant increase in pressure within the left renalvein can cause hematuria, flank pain, hypertension, andeven ureteral obstruction due to the formation of second-ary collateral venous varicosities.1 Additional clinical find-ings may include symptoms of pelvic venous congestion,including dyspareunia, dysmenorrhea, and dysuria. Thephenomenon may result in varicosities in the vulva andgluteal regions.2

Numerous treatment modalities have been described,including left renal vein transposition, nephropexy, renalvein stenting, and renal autotransplantation, with varyingdegrees of success. Except for endoluminal venous stent-ing, all of these procedures have involved a traditional opensurgical approach with the associated disadvantages of in-cisional discomfort. Herein, we describe a novel, minimallyinvasive treatment option for nutcracker syndrome: laparo-scopic splenic to left renal vein bypass.

CASE REPORT

A 29-year-old woman with a 2-year history of recurrent, severeleft-sided flank pain underwent a computed tomography (CT) scanthat revealed a left kidney with speckled intrarenal calcifications, anatrophic and scarred left lower pole, a normal right kidney, and aleft ovarian cyst. Initially, the ovarian cyst was thought to be the

From the Section of Laparoscopic and Robotic Surgery, Glickman Urolog-ical Institute, Cleveland Clinic Foundation.

Competition of interest: Dr Gill is a consultant for Hansen Medical Inc.Reprint requests: Inderbir S. Gill, MD, Section of Laparoscopic and Robotic

Surgery, Glickman Urological Institute, Cleveland Clinic Foundation,9500 Euclid Ave, A-100, Cleveland, OH 44195 (e-mail: gilli@ccf.org).

0741-5214/$36.00Copyright © 2009 by the Society for Vascular Surgery.

doi:10.1016/j.jvs.2008.11.062

cause of her pain, and she underwent laparoscopic left ovarian cystremoval, without resolution of symptoms. The pain continued inan unremitting fashion, requiring narcotic medications for relief,causing difficulty in her continuing her occupation as a hairdresser.

Follow-up enhanced CT imaging suggested an apparent arte-riovenous malformation (AVM) in the region of the atrophic leftlower pole of the kidney. The patient was referred to urology witha recommendation for percutaneous embolization of the AVM. Aurine dipstick analysis revealed trace blood, but results of urine

Fig 1. Venogram shows venous obstruction of the left renal veinat the level of the junction of the aorta and superior mesentericartery (arrow).

culture, cytology, cystoscopy, and upper urinary tract studies were

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JOURNAL OF VASCULAR SURGERYMay 20091320 Chung and Gill

Fig 2. Illustration shows nutcracker phenomenon with atrophic left lower pole and multiple collateral venous

varicosities.

Fig 3. Regional vascular anatomy demonstrates location of splenic vein in relation to left renal vein.

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all negative. The result of her physical examination was unremark-able, and the serum creatinine level was 0.8 mg/dL (normalreference range, 0.7-1.4 mg/dL).

Selective arteriography revealed no evidence of an AVM;however, during the venous phase, the left kidney showed exten-sive venous collateralization emanating from the gonadal system,with minimal venous drainage through the left main renal vein intothe vena cava (Figs 1-3). Selective phlebography with pressuremanometry through the femoral vein revealed an elevated 4-mmHg pressure gradient between the left renal vein and the vena cava,consistent with venous obstruction at the level of the SMA. Thegonadal vein was not injected with contrast.

A mercapto acetyl triglycine (MAG-3) renal scan revealed 31%differential function of the left kidney with prompt urinary drain-age. Given the patient’s spectrum of findings, the presumptivediagnosis was nutcracker syndrome. The patient was advised of heroptions, including observation, nephrectomy, endoluminal stent-ing, autotransplantation, and renal vein bypass. The patient electedlaparoscopic splenic to left renal vein bypass.

A standard 5-port transperitoneal technique was used. Whenthe left kidney was exposed, large venous collaterals emanatingfrom the lower pole of the kidney and the gonadal system werereadily appreciated. Care was taken to avoid disrupting any of theseengorged venous collaterals. The gonadal vein was traced cephaladto the main left renal vein, which was skeletonized. The left adrenalvein, left gonadal vein, and a lumbar branch were preserved. Theleft renal artery was circumferentially dissected posterior to therenal vein at its aortic ostium.

Attention was then focused on the splenic vein. The pancreasand spleen were reflected medially to identify the splenic vein,which was carefully dissected free from the surrounding pancreatictissue. In doing so, multiple small tributary venous branches werecontrolled with clips or electrocautery. The splenic vein was thusmobilized distally towards the splenic hilum, where it was dividedusing an Endo-GIA stapler (US Surgical, Norwalk, Conn) andadditional clips. A bulldog clamp was placed on the proximal stemof the splenic vein, the distal staple line was excised, and heparin-

Fig 4. Intraoperative photograph shows alignment of splenicvein on top of left renal vein before the anastomosis.

ized saline was used to flush the vein. The splenic vein was

spatulated and was advanced towards the left renal vein to confirmtension-free end-to-side approximation (Fig 4).

Intravenous mannitol and furosemide were administered, andblood vessels were individually occluded with separate bulldogclamps in the following sequence: left renal artery, proximal leftrenal vein, left adrenal vein, left gonadal vein, and distal left renalvein. A venotomy was created on the superior edge of the renalvein, just distal to the adrenal vein. The renal vein lumen wasflushed with heparinized saline and an end-to-side anastomosis wasinitiated in the distal corner with a running single armed 5-0polydioxanone suture to complete the posterior wall of the anas-tomosis. Another 5-0 polydioxanone suture was used to completethe anterior wall of the anastomosis, and the two sutures were tiedtogether (Fig 5). Before the anastomosis was completed, the veinlumen was flushed with heparinized saline. The venous bulldog

Fig 5. Intracorporeal suturing of splenic vein to left renal veinanastomosis.

Fig 6. Completed anastomosis. Note smaller diameter of leftrenal vein and larger diameter of splenic vein, indicating preferen-tial venous outflow through splenic vein.

clamps were removed, followed by the arterial clamp.

anas

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RESULTS

Total warm ischemia time was 37 minutes, and theanastomosis was watertight immediately upon unclamping.Interestingly, upon unclamping, the luminal diameter ofthe splenic vein appeared to increase to twice its nativediameter, and the proximal left renal vein appeared lessdistended (Figs 6 and 7). This indicated preferential venousdrainage from the kidney through the newly created sple-norenal bypass, providing presumptive intraoperative con-firmation of nutcracker obstruction of the proximal leftrenal vein. A Jackson-Pratt drain was placed through thelateral 5-mm port site. Total operative time was 3.5 hours,and blood loss was �50 mL.

The patient was given nothing by mouth the firstpostoperative day to avoid undue stress on the pancreas.Serum amylase and lipase levels were mildly elevated, butthe patient remained completely asymptomatic during andafter her hospital stay. Her diet was advanced, and thepatient was discharged home on postoperative day 2. Thedrain was removed 1 week postoperatively. At a follow-upof 8 months, the patient reports complete resolution of herpreviously debilitating flank pain, without any need foranalgesics. However, the patient has refused formal post-operative follow-up, including laboratory analysis or imag-ing studies that could objectively document hemodynamic

Fig 7. Illustration shows the completed

resolution of the nutcracker syndrome.

DISCUSSION

The proliferation of minimally invasive techniques inurologic surgery has reduced morbidity and resulted inquicker patient convalescence, with equivalent results totraditional open surgery in many applications. Our teamhas previous experience with laparoscopic renovascular sur-gery, as we have performed successful laparoscopic aorta–left renal artery bypass in a porcine model3 and successfullaparoscopic repair of a renal artery aneurysm.4

In the treatment of nutcracker syndrome, various treat-ment modalities have been described. Intraluminal andextraluminal renal vein stenting, gonadocaval venous by-pass, left renal vein transposition, renal autotransplantation,and nephropexy have been performed with varying success.Extraluminal venous stenting has been described with apolytetrafluoroethylene graft wrapped around the left renalvein at the site of extrinsic compression by the SMA.2,5 Thesuccessful transposition of the left renal vein (renocavalreimplantation) has also been described.1,6,7 Nephropexywas described in a situation in which true extrinsic compres-sion by the SMA did not exist, but instead a stretch phe-nomenon with renal vein compression over the aorta due toposterior renal ptosis.8 Renal autotransplantation has alsobeen performed successfully.9,10 All of these therapeutic

tomosis and regional vascular anatomy.

options have been performed with open surgery.

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Recently, percutaneous intravascular stenting of the leftrenal vein has been attempted with good results. Parket al11 reported the placement of an endoluminal 18-mmintravascular renal vein stent with relief of symptoms duringa follow-up of 4 months. Potential pitfalls of endoluminalvenous stenting include poststenting fibromuscular hyper-plasia leading to venous occlusion.2 In this patient, weattempted a novel laparoscopic method for treating thisanatomic anomaly.

Many putative mechanisms for the nutcracker syn-drome have been postulated, from abnormal insertion ofthe SMA1 to ptosis of the kidney.8 The CT scan of ourpatient revealed that the left kidney was displaced morecephalad than normal, which could subject the left renalvein to extrinsic compression under the SMA. Because theleft kidney and left renal vein were located more cephaladthan normal, this placed the renal vein close to the splenicvein, facilitating laparoscopic anastomosis. Our opinionwas that operating extensively near the SMA, as in perform-ing a renal vein transposition, would create an unduehazard, and that the extensive venous collaterals surround-ing the lower pole would preclude intervention such asgonadocaval bypass, making the splenorenal venous bypassa more logical choice.

The technical performance of this procedure gives anadditional indication to the burgeoning armamentarium ofadvanced minimally invasive urologic reconstructive proce-dures. We believe that careful patient selection and adher-ence to established surgical principles will continue toexpand the applicability of these techniques in complicatedsituations, like ours, which until now have been thought tobe beyond the reach of minimally invasive surgery. Onemust keep in mind, however, that this is a technicallydifficult procedure, with a potential complication riskgreater than less invasive procedures such as endoluminalstenting. More experience is required to make conclusionsabout its feasibility in contemporary practice.

Limitations with this patient include the lack of post-operative imaging studies to confirm the flow of blood intothe splenic vein. In addition, because the splenic vein

pressure was not measured preoperatively, the possibility

exists that the baseline splenic vein pressure exceeded thatof the obstructed left renal vein, which would not allow forflow into the newly created venous bypass.

CONCLUSIONS

Splenic to left renal venous bypass appears to be anefficacious procedure in the treatment of nutcracker syn-drome. This novel technique, and its laparoscopic perfor-mance, further extends the applications of minimally inva-sive surgery. Longer follow-up and further experience areneeded to evaluate the efficacy of this procedure in the longterm.

Many thanks to Simon Kimm, MD, for his outstandingillustrations.

REFERENCES

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2. Scultetus AH, Villavicencio JL, Gillespie DL. The nutcracker syndrome:its role in the pelvic venous disorders. J Vasc Surg 2001;34:812-9.

3. Hsu TH, Gill IS, Sung GI, Meraney A, McMahon JT, Novick AC.Laparoscopic aortorenal bypass. J Endourol 2000;14:123-31.

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5. Barnes RW, Fleisher HL, Redman JF, Smith JW, Harshfield DL, FerrisEJ. Mesoaortic compression of the left renal vein (the so-called nut-cracker syndrome): repair by a new stenting procedure. J Vasc Surg1988;8:415-21.

6. Stewart BH, Reiman G. Left renal venous hypertension “nutcracker”syndrome. Urology 1982;20:365-9.

7. Shaper KRL, Jackson JE, Williams G. The nutcracker syndrome: anuncommon cause of hematuria. Br J Urol 1993;74:144-6.

8. Wendel RG, Crawford ED, Hehman KN. The “nutcracker” phenom-enon: an unusual cause for renal varicosities with hematuria. J Urol1980;123:761-3.

9. Shokeir AA, El-Diasty TA, Ghoneim MA. The nutcracker syndrome:new methods of diagnosis and treatment. Br J Urol 1994;74:139-43.

10. Chuang CK, Chu SH, Lai PC. The nutcracker syndrome managed byautotransplantation. J Urol 1997;157:1833-4.

11. Park YB, Lim SH, Ahn JH, Kang ET, Myung SC, Shim HJ, Yu SH.Nutcracker syndrome: intravascular stenting approach. Nephrol DialTranplant 2000;15:99-101.

Submitted Aug 26, 2008; accepted Nov 19, 2008.