title: Nutcracker Syndrome: An Update on Current Diagnostic Criteria and Management Guidelines.
abstract: BACKGROUND
  Nutcracker syndrome (NCS) describes left renal vein compression between the superior mesenteric artery and the aorta. Although uncommon, it is an important diagnosis due to the important morbidity associated with it, including the risk of chronic kidney disease from long-term left renal vein (LRV) hypertension and the risk of LRV thrombosis.
  
  
  METHODS
  This article reviews the literature on NCS, particularly with respect to the diagnostic accuracy of different imaging modalities and the success rates, complications, and long-term follow-up data associated with various surgical interventions.
  
  
  CONCLUSIONS
  The diagnosis of this condition is based on a stepwise work-up with history and clinical examination, followed by Doppler ultrasonography, computed tomography, magnetic resonance imaging, intravascular ultrasound (IVUS) and phlebography with measurement of the renocaval pressure gradient. Management is determined by symptom severity; often symptom resolution occurs following a conservative approach. However, in some cases, surgical management is required, particularly when conservative management is unsuccessful. When it comes to the surgical management of NCS three main pathways exist: open surgery, laparoscopic surgery and endovascular approaches, with the latter 2 becoming increasingly popular due to their minimal invasiveness. Additionally, cases involving the use of robotic surgery in the management of NCS have been reported.
  
  
  CONCLUSIONS
  Despite the rarity of NCS, its recognition and management are important. This article has explored the evidence basis for conservative, medical and surgical options.
authors.affiliation: North West Thames Foundation School, Watford General Hospital, Watford, UK.
authors.forename: K
authors.initials: K
authors.lastname: Ananthan
authors.affiliation: Academic Section of Vascular Surgery, Division of Surgery, Department of Surgery & Cancer, Imperial College London, Charing Cross Hospital, London, UK.
authors.forename: S
authors.initials: S
authors.lastname: Onida
authors.affiliation: Academic Section of Vascular Surgery, Division of Surgery, Department of Surgery & Cancer, Imperial College London, Charing Cross Hospital, London, UK. Electronic address: a.h.davies@imperial.ac.uk.
authors.forename: A H
authors.initials: AH
authors.lastname: Davies
mesh_terms: D057510:Endovascular Procedures / Q000009:adverse effects; D006801:Humans; D010535:Laparoscopy / Q000009:adverse effects; D011237:Predictive Value of Tests; D059228:Renal Nutcracker Syndrome / Q000000981:diagnostic imaging* / Q000453:epidemiology / Q000503:physiopathology / Q000601:surgery*; D012307:Risk Factors; D016896:Treatment Outcome; D014656:Vascular Surgical Procedures / Q000009:adverse effects
keywords: Haematuria; Mesenteric ischaemia; Renal nutcracker syndrome; Renal vein; Superior mesenteric artery syndrome