This presentation gives a summary of the approach to a patient with nutcracker syndrome. It also gives various treatment modalities available to the treating physician.

1. Nutcracker syndrome
Presented by Dr. Sanjay Dange
Guide & Mentor – Dr. Ajit Sawant (Professor & HOD)
Mentor – Dr. Prakash Pawar(Professor)
Mentor – Dr. Sunil Patil (Associate Professor)
05/06/2021

2. History
• Earliest pathological description – Grant (1937)
• First clinical report – El Sadr and Mina (1950)
• Term ‘nutcracker’ – de Schepper (1972)

3. What is Nutcracker Syndrome (NS)?
• Nutcracker Phenomenon [NCP] (aka left renal vein entrapment) – impeded
outflow from left renal vein (LRV) into the IVC due to extrinsic LRV compression
• NCP demonstrated as lateral (hilar) dilatation and medial (meso-aortic) narrowing
• NS – clinical symptoms + demonstrable features of NCP

4. Types of NS
• Anterior NS – compression of LRV between SMA and Aorta (analogous to SMA syndrome/Wilkie
Syndrome)
• AMA < 35 degrees → Aorto-mesentric narrowing of LRV → increasing intraluminal pressure →
Renal varices

5. • Posterior NS – LRV compressed between aorta and vertebral body

6. Pathological processes leading to LRV compression
• Pancreatic neoplasm
• Retroperitoneal tumors
• Overarching testicular artery
• Lordosis
• Reduced retroperitoneal and mesenteric fat
• pregnancy

7. DEMOGRAPHIC CHARACTERISTICS
• Exact prevalence not known
• Slightly higher in females
• Not hereditary
• Mostly 2nd or 3rd decade of life
• 2nd peak in middle aged women

8. CLINICAL FEATURES
• Positionality of symptoms – hallmark (Doppler Ultrasound + physical findings)
• Hematuria (MC) – rupture of thin-walled varices (elevated venous pressure)
• Abdominal and left flank pain (clot colic, gonadal vein pain syndrome radiating to
posteromedial thigh and buttock)
• Varicocoele in 9.5% of affected men
• Orthostatic proteinuria
• Chronic fatigue syndrome in NS associated with high LRV:IVC pressure gradient
• Pelvic congestion – chronic pelvic pain a/w dyspareunia, dysuria, dysmenorrhoea,
pelvic varicocoele

9. DIAGNOSIS
• Doppler Ultrasound (DUS)
• CT venography (CTV)/ MR venography (MRV)
• Contrast venography (CV) + Intravascular ultrasound (IVUS)

10. DUS
• First line study
• Sensitivity 69-90%
• Specificity 90-100%
• Aorto- mesenteric : hilar PSV > 4.2 to 5.0 → one of the diagnostic criteria

12. • Advantage- real time assessment of flow and peak velocities
• Disadvantages-
• Variability with positional changes
• Technical difficulty from small sampling area
• Inter-observer variability
• Transducer compression artifacts

13. CT /MR VENOGRAPHY
• Bird beak sign
• AMA angle <35 degrees
• LRV hilar diameter: aorto-mesenteric diameter >4.9 – highest
diagnostic accuracy (Specificity – 100%)

17. • Disadvantage
• Not Dynamic modality
• Does not measure Flow velocity & Direction
• Radiation exposure

18. CV + IVUS
• Gold standard
• Allows visualization and selective catheterization of collaterals like LGV
• Renocaval pressure gradient >3mmHg (normal = 0-1 mmHg) → Diagnostic of NS
• IVUS allows real time visualization of dynamic LRV compression and guides the
selection of size and location of stent placement (Specificity – 90%)

19. Diagnostic
Modalities
DUS
Aorto-mesenteric:
hilar PSV >4.2 to 5.0
CTV/MRV
LRV hilar: aorto-
mesenteric
diameter > 4.9
SMA branching
angle <35 degrees
CV and IVUS
Renocaval pressure
gradient >3mm Hg
A systematic review on management of nutcracker syndrome

20. Current management approach for left renal vein entrapment
syndrome: the so-called ‘Nutcracker’ syndrome

21. Current management approach for left renal vein entrapment
syndrome: the so-called ‘Nutcracker’ syndrome

23. A systematic review on management of nutcracker syndrome
TREATMENT
MODALITIES
NON OPERATIVE
YOUNG PATIENT
WITH MILD
SYMPTOMS
OPEN SURGICAL
LRV Transposition
Renal auto-transplant
Gonado-caval bypass
LAPAROSCOPIC
EXTRAVASCULAR
STENT PLACEMENT
ENDOVASCULAR
HYBRID

24. Indications of Surgery
• Gross Hematuria (Especially Recurrent)
• Severe Symptoms :
• Flank pain
• Anemia
• Persistent Orthostatic proteinuria
• Ineffective Conservative Mx > 24 mths in pt < 18 years or after 6
months in adults

25. Conservative Management
• Pt < 18 yrs of age →growth → ↑ intraabdo. Fibrous tissue at SMA
origin → Release entrapped LRV
• Weight gain → ↑ Retroperitoneal Adipose tissue
• Medical Treatment
• ACE inhibitors → proteinuria
• Aspirin → Improve renal perfusion

26. Open Surgery
• LRV Transposition → Gold standard treatment (M/C)
• Auto Transplantation
• Pelvic Venous disease prior to LRV hypertension (LGV embolization &
ligation)

27. LRV Transposition
LRV transposed to caudal location on IVC , AMA angle and distance are wider and larger respectively

28. LRV Transposition with patch venoplasty
Patch venoplasty → Permanent injury to LRV post long standing entrapment (fibrosis/ fixed stenosis/ thrombosis)

29. LRV Transposition with Saphenous vein cuff
Extension Cuff →Inadequate vein length

30. Left Gonadal Vein Transposition
LGV transposition → NCS with LGV incompetence with symptomatic Pelvic venous disease (varicocoele or PCS)

31. • Left Gonadal Vein preferably preserved → subsequent coil
embolization or secondary surgical bypass

32. Renal Autotransplant
• Advantage – Corrects posterior Nephroptosis
• Disadvantage –
• Extensive dissection
• Long period of renal ischemia
• Additonal anastomoses of renal artery and ureter

33. Laparoscopic Surgery
• Laparoscopic Extravascular stent placement
• Stent – expanded PTFE graft
• Laparoscopic LRV – IVC transposition

34. Endovascular Stenting

35. •Endovascular stenting – preferably used in treatment
of NCS with PCS
•Complication depends on Type/ size of stent, Surgeon
experience
•Stent migration – MC complication
•Other complications:
• In stent re-stenosis
• Thrombosis
• Kinking
• fracture

36. Hybrid Repair
• Open + Endovascular stenting
• LRV Transposition with Patch venoplasty (GSV) + Inra op stenting with
slight over sized self-expanding stent

38. Advantages
•Transpositon - removes LRV from max compression
•Patch venoplasty – allows use of large caliber stent →
patency
•Self- expanding stent - prevents sustained/ recurrent
extrinsic compression
•Transfixation – prevents stent migration

42. • 34 yr old female
• c/o occasional left flank pain
• One episode of hematuria
• No other complaints
• Family complete – 4 children
• h/o TL done

43. Blood Investigation
• Hb – 11.8
• TLC – 5400
• Platelet – 153000
• Creat – 0.7

44. Ultrasound
Right kidney Left kidney
8.4 x 3.6 cm 8.6 x 3.9 cm
normal 2.9 x 2.7 cm simple cyst at MP

45. Urine rm
• NAD

46. CT Urography

51. CT Urography
• RK – 8.4 x 4.7 x 4.9 cm
• LK – 9.3 x 5 x 4.8 cm, simple cyst 3 x 2.5 cm at mid pole
• B/L good nephrogram with prompt excretion of contrast
• LRV compressed by SMA, AMA 30 degree, compression ratio 1.3
• Bilateral pelvic and ovarian veins dilated