2. US & Doppler US in liver transplantation
Surgical techniques of LT
Normal US & Doppler US in LT
Reversible Doppler findings in post-operative period
Doppler US of LT complications
US of LT complications
4. Types of liver graft
• Full cadaveric graft
• Split cadaveric graft
• Reduced cadaveric graft
• Living donor graft
• Domino transplantation
5. Liver transplant anatomy
Singh AK et al. RadioGraphics 2010; 30: 339 – 351
Orthotopic liver transplant Living donor liver transplant
6. Surgical techniques of LT
• Surgical procedure Whole liver, single lobe, segmental
• Gallbladder Normally removed
• PV, HA, & BT End-to-end anastomoses usually
• IVC Piggy-back technique
Avoids clamping IVC during surgery
• Conduit vessels Discrepancies in vessel diameter
Portal vein thrombosis
Increased risk of thrombosis
It is important to know type of surgical procedure performed,
but it is rarely available
7. Vascular complications are the most frequent
adverse events after LT
Early correction of vascular complications could
permit complete recovery or may save the graft
Timely detection is important
9. Imaging evaluation of LT
Disease Initial study Subsequent study Final invasive study
Vascular Doppler US MR angiography
CT angiography
CEUS
Angiography
Biliary Doppler US MRCP
CT scan
Scintigraphy
ERCP
PTC
Ajay K. Singh RadioGraphics 2010; 30: 339 – 351.
11. Frequency of Doppler US exam
• First exam 24 – 48 hour after transplantation
Confirm patency of hepatic vessels
• Then Every 3 – 5 days for first 2 weeks
• Additional exam 4 week after transplantation
Piscaglia F, Sidhu P, Brabrand K and Borghi A
EFSUMB – European Course Book – Liver Transplantation – 2011.
No RCT investigates optimal frequency
Each centre decides its own policy
More frequent exam in patients at higher risk
12. US & Doppler US of LT
• US exam Hepatic parenchyma
Bile ducts
• Doppler exam Hepatic vessels Hepatic artery
Portal vein
Hepatic veins & IVC
Splenic artery
Piscaglia F, Sidhu P, Brabrand K and Borghi A
EFSUMB – European Course Book – Liver Transplantation – 2011.
13. Normal hepatic artery
Piscaglia F, Sidhu P, Brabrand K and Borghi A
EFSUMB – European Course Book – Liver Transplantation – 2011.
Intercostal approach Epigastric approach
Right hepatic artery Left hepatic artery
14. Normal hepatic artery
Resistance index (RI) or Pourcelot’s index
RI: S – ED / S
Normal: 0.5 – 0.8
Buscarini E et al. Ultraschall Med 2004 ; 25 : 348 – 55.
15. Normal hepatic artery
Accleration Time (AT) or Rise Time (RT)
Time in seconds from onset of systole to peak systole
Normal value: ≤ 0.08 second
16. Normal spectral Doppler of HA
* Buscarini E et al. Ultraschall Med 2004 ; 25 : 348 – 55.
Diameter* 5 ± 1 mm
PSV 70 ± 10 cm/sec
RI 0.50 – 0.80
RT < 0.08 sec
17. Normal hepatic artery
One or two systolic peaks
Piscaglia F, Sidhu P, Brabrand K and Borghi A
EFSUMB – European Course Book – Liver Transplantation – 2011.
RI Calculated from highest peak, early or late
AT Calculated considering first peak
18. Normal portal vein
• Diameter Upper limits of normal: 13 – 16 mm
> 20 – 30% increase with food & inspiration
• Flow direction Towards liver (hepatopetal)
Throughout entire cardiac cycle
• Velocity Varies greatly (Max – Mean – Min – TAMV)
Mean velocity: 15 – 18 cm/s
Varies with cardiac & respiration activity
Undulating appearance of waveform
Goyal N et al. Clin Radiology 2009 ; 64 : 1056 – 1066.
19. Normal portal vein
Normal monophasic waveform with mild phasicity
Sanyal R et al. RadioGraphics 2012 ; 32 : 199 – 211.
Duplex US of main PV
20. Helical portal vein flow
Donor PV > recipient PV
If not properly recognized, it can produce
the mistaken impression of PV flow reversal
Robinson KA et al. Ultrasound Quarterly 2009 ; 25 : 3 – 13.
21. Helical portal vein flow
Mimic of hepatofugal flow
Wachsberg RH et al. RadioGraphics 2002 ; 22 : 123 – 140.
Hepatopetal flow within liver confirms that net flow is hepatopetal
22. Causes of helical portal vein flow
Near bifurcation
• Normal subjects 2%
• Severe liver disease 20%
• TIPS
• Post-liver transplantationDonor PV > recipient PV
• Portal vein stenosis
Robinson KA et al. Ultrasound Quarterly 2009 ; 25 : 3 – 13.
23. Piggy-back anastomosis of the IVC
Schematic image
Subcostal scan to visualize
the anastomosis
US & color Doppler US
Piscaglia F, Sidhu P, Brabrand K and Borghi A
EFSUMB – European Course Book – Liver Transplantation – 2011.
–
24. Normal hepatic vein
Normal triphasic waveform flow
Spectral Doppler of hepatic vein
Piscaglia F, Sidhu P, Brabrand K and Borghi A
EFSUMB – European Course Book – Liver Transplantation – 2011.
25. Normal hepatic vein waveform – 3 components
Kruskal JB et al. RadioGraphics 2004 ; 24 : 657 – 675.
A Atrial systole
S Ventricular systole
D Atrial diastole
A
S D
S wave > D wave
Commonly described as triphasic
28. Starry sky pattern
Sanyal R et al. RadioGraphics 2012 ; 32 : 199 – 211.
US on 1st post-operative day US 3 days after OLT
Normal hepatic echotexture
Echogenic portal venules & diminished
parenchymal echogenicity (edema)
29. Pneumobilia
Sanyal R et al. RadioGraphics 2012 ; 32 : 199 – 211.
US image on first postoperative day after OLT
Normal finding after bilio-enteric anastomosis in OLT
30. Pleural effusion
Sanyal R et al. RadioGraphics 2012 ; 32 : 199 – 211.
Moderate right pleural effusion, a common finding
Usually resolve within few days
US image on 1st post-operative day after OLT
31. Elevated PSV in hepatic artery
Sanyal R et al. RadioGraphics 2012 ; 32 : 199 – 211.
1st postoperative day of OLT
PSV: 283 cm/sec – normal RI
Due to anastomotic edema
Perivascular vibration is seen
PSV: 192 cm/sec
Resolution of anastomotic edema
No peri-vascular vibration
3 days after OLT
32. 1st postoperative day of OLT
Sanyal R et al. RadioGraphics 2012 ; 32 : 199 – 211.
Decrease resistance index in hepatic artery
Elevated PSV: 303 cm/sec
Low RI: 0.45
3 days after OLT
Decreased PSV: 118 cm/sec
Increased RI: 0.56
Resolution of narrowing secondary to anastomotic edema
33. Reversed diastolic flow in hepatic artery
Sanyal R et al. RadioGraphics 2012 ; 32 : 199 – 211.
1st postoperative day of OLT 3 days after OLT
Normal PSV: 55 cm/sec
Reversed or absent diastolic flow
Normal waveform
Improved RI: 0.87
34. Tardus parvus waveform in hepatic artery
Sanyal R et al. RadioGraphics 2012 ; 32 : 199 – 211.
1st postoperative day of OLT 3 days after OLT
Normalization of tardus parvus
Increased PSV: 53 cm/sec
Improved RI: 0.62
Tardus parvus waveform
Low PSV: 23 cm/sec
Low RI: 0.43
35. Increased velocity in portal vein
Sanyal R et al. RadioGraphics 2012 ; 32 : 199 – 211.
1st postoperative day of OLT
Increased PV velocity: 149 cm/sec
Decreased portal resistance
3 days after OLT
Improved turbulence
Normal PV: 54 cm/sec
36. Pulsatile flow in portal vein
Common finding in congestive heart failure
Sanyal R et al. RadioGraphics 2012 ; 32 : 199 – 211.
1st postoperative day of OLT
Pulsatile PV waveform
due to altered hemodynamics
3 days after OLT
Normal monophasic flow
37. Monophasic flow in hepatic veins
Sanyal R et al. RadioGraphics 2012 ; 32 : 199 – 211.
1st postoperative day of OLT
Monophasic flow in MHV
Graft edema
3 days after OLT
Normal triphasic waveform
38. Turbulence at HV-IVC anastomosis
Sanyal R et al. RadioGraphics 2012 ; 32 : 199 – 211.
1st postoperative day of OLT
Turbulence at HV-IVC anastomosis
3 days after OLT
Resolution of turbulence
40. Vascular complications of LT
• Hepatic artery Stenosis – Thrombosis – PSA
• Portal vein Stenosis – Kinking – Thrombosis
• Hepatic veins & IVC Stenosis – Kinking – Thrombosis
• Splenic artery Splenic artery steal syndrome (SASS)
Piscaglia F, Sidhu P, Brabrand K and Borghi A
EFSUMB – European Course Book – Liver Transplantation – 2011.
41. Presentation of vascular complications after LT
Complication Time of presentation after LT
HA thrombosis First two weeks
Late HAT occurs but less devastating
HA stenosis Few weeks to several months
PV thrombosis Within one month
PV stenosis Usually late (> 6 months)
HV stenosis Usually late (> 6 months)
Sanyal R et al. Indian J Radiol Imag 2014 ; 24 : 360 -366.
43. HA thrombosis – Systematic review
Most severe complications especially when abrupt
• Incidence 2 – 12% of adult recipients
2 – 6% in experienced centers
• Peak occurrence Seventh day following LT
• Re-transplantation Up to 60%
• Mortality 33%
• Doppler US Identify up to 92%
Bekker J, Ploem S, de Jong KP. Am J Transplant 2009 ; 9 : 746 - 57.
44. Complications of HA thrombosis
Transplanted liver extremely sensitive to arterial ischemia
• Primary liver non-function
• Hepatic infection & abscesses
• BT ischemia Lumen filled with biliary necrotic casts
Irreversible Biliary stenosis with peritoneal spillage
Diffuse & involve all IH branches
Only biliary surgical anastomosis (often)
Piscaglia F, Sidhu P, Brabrand K and Borghi A
EFSUMB – European Course Book – Liver Transplantation – 2011.
45. Manifestations of HA thrombosis
• General malaise, fullness or fever
• Pain not usually present Denervated transpl liver
• Elevated liver enzymes Elevated γGT & AP
• Liver failure Elevated bilirubin
Prolonged PT
46. Doppler US in HA thrombosis
Visualize artery in hilum & both lobes
• Fasting examination Arterial buffer vasoconstriction
• Adjust color scale
• Doppler gate near PV
• Wider Doppler gate Normal arterial spikes within PV
Arterial thump in thrombosis
• CEUS 1.2 – 2.4 ml SonoVue IV
Low mechanical index
• Further investigations CECT – angiography
Piscaglia F, Sidhu P, Brabrand K and Borghi A
EFSUMB – European Course Book – Liver Transplantation – 2011.
47. Doppler US in HA thrombosis
• HA in hilum Absence of visualization
• Intra-hepatic branches RI ˂ 0.50
AT ˃ 0.08 sec
Identification of just one parameter is enough to
prompt rapid further investigations
49. Doppler US in HA thrombosis
Sanyal R et al. Indian J Radiol Imag 2014 ; 24 : 360 - 366.
Tardus parvus in LHA
Flow in LHA does not exclude HAT
CT angiogram
Thrombosis of main HA
Doppler ultrasound
50. Hepatic artery stenosis
Horrow M et al. AJR 2007; 189 : 346 – 351.
Flow in portal vein
No flow in hepatic artery
Power Doppler at porta hepatis
Complete occlusion
of hepatic artery
CT angiogram
51. Biliary cast syndrome
First described in 1975
• Incidence 2.5% after OLT – Less than sludge & stones
• Morphology Hard dark material in biliary ducts
Similar shape to BD
• Symptoms High fever, jaundice, cholestasis
• Characterized Multiple intra-hepatic biliary strictures
Ductal dilatation
Intrahepatic abscesses
Biliary anastomotic leakage
• Treatment Surgery is treatment of choice
Endoscopic techniques successful & safe
Yang Ylet al. World J Gastroenterol 2013 ; 19 (43): 7772 – 77.
52. Biliary cast syndrome
Ha SI et al. Korean J Gastroenterol 2012 ; 60 : 382 – 385.
Biliary cast
removed endoscopically
Hyperechoic material in CBD
Initially thought as ascariasis
Gray scale US
Longitudinal tubular
filling defect in CBD
ERCP
53. Biliary cast syndrome
Biliary duct necrosis
Rubens DJ. Ultrasound Clin 2007 ; 2 : 391 – 413.
Linear echogenic debris
with acoustic shadows
Transverse US
Low RI (<0.5)
HA stenosis/thrombosis
Color Doppler US
Extensive BT necrosis
Resulting liver abscess
CT scan
Abscess obscured on US because of shadowing from air in the ducts
54. Hepatic artery stenosis
Milder effect than thrombosis
• Incidence Up to 10%
• Site Most often at anastomostic site
Consequence of arterial kinking
• Manifestation Bile duct strictures from ischemia
Piscaglia F, Sidhu P, Brabrand K and Borghi A
EFSUMB – European Course Book – Liver Transplantation – 2011.
High degree stenosis leads to biliary ischemia
55. Doppler US of HA stenosis
• At stenosis Aliasing on color Doppler
PSV ˃ 2m/sec
• Post-stenosis Tardus-parvus wave
RI ˂ 0.5
AT ˃ 0.08 sec
Stenosis could be corrected radiologically or surgically
Piscaglia F, Sidhu P, Brabrand K and Borghi A
EFSUMB – European Course Book – Liver Transplantation – 2011.
56. Hepatic artery stenosis
Main hepatic artery
Turbulent flow & high PSV (4.7 m/s)
Intra-hepatic artery
Tardus-parvus, low RI & long AT
Angiogram: high degree HA stenosis
Piscaglia F, Sidhu P, Brabrand K and Borghi A
EFSUMB – European Course Book – Liver Transplantation – 2011.
57. HA pseudo-aneurysm (PSA)
Extra-hepatic PSA considered as surgical urgency
• Incidence Less than 1%
• Symptoms Usually asymptomatic
Rupture with life-threatening hemoperitoneum
• Causes Extrahepatic Infection (mycotic PSA)
Defective reconstruction
Intra-hepatic Percutaneous interventions
Focal infection of parenchyma
• US US diagnosis is difficult
Hypoechoic collection near arterial anastomosis
should be evaluated with CDUS or CEUS
Piscaglia F, Sidhu P, Brabrand K and Borghi A
EFSUMB – European Course Book – Liver Transplantation – 2011.
58. HA pseudo-aneurysm
Leong L. Biomed Imaging Interv J 2006; 2(2):e17.
High PSV at neck of PATurbulent flow in a lesion near HA
DSA of celiac axis: pseudoaneurysm
59. O’Briena J et al. European J Radiol 2010; 74 : 206 – 213.
HA pseudo-aneurysm / yin-Yang pattern
Selective arteriography
Gray-scale US
Echopoor lesion in the liver
Color Doppler US
Swirling or “yin-yang” pattern
60. Splenic artery steal syndrome (SASS)
First described by Manner in 19911
• Clinic Graft ischemia in early postoperative period
non-specific2 Less fulminant than HAT
Elevated liver enzymes first
Then cholestasis, biliary damage, rejection
• Exclude Hepatic arterial thrombosis
Hepatic arterial thrombosis
Acute rejection
• Treatment Splenic artery embolization
1Manner M et al. Transpl Int 1991; 4 : 122 – 124.
2Sanyal R, Shah SN. J Ultrasound Med 2009; 28: 471 – 477.
61. US Doppler of SASS
• Hepatic artery High RI in IH & EH arteries
RI usually 0.8 & 1 in diastolic reversal
Can be transient post-operative finding
Can be indicator of acute rejection
• Splenic artery Increased flow in splenic artery
• Portal vein High portal vein velocity
Sanyal R, Shah SN. J Ultrasound Med 2009 ; 28 : 471 – 477.
HAT & stenosis are 2 other causes of graft ischemia
Doppler US very sensitive for their diagnosis
Low-resistance or absent flow distal to obstruction
62. Doppler US of SASS / Hepatic artery
Sanyal R, Shah SN. J Ultrasound Med 2009; 28 : 471 – 477.
Right hepatic artery
Diastolic reversal
Left hepatic artery
Diastolic reversal
Main hepatic artery
Diastolic reversal
63. Doppler US of SASS / PV & splenic artery
Sanyal R, Shah SN. J Ultrasound Med 2009 ; 28: 471 – 477.
Hyperdynamic splenic artery
PSV: 272 cm/s
Hyperdynamic main PV
Mean PV velocity 115 cm/s
65. Portal vein
Stenosis – Kinking – Thrombosis
• Incidence 1 – 2% of patients
• Picture Portal hypertension
Hepatic failure
Ascites
or all of these
Do not usually lead to liver failure or graft loss
66. Doppler US of PV thrombosis
• Ultrasound Internal echoes within PV
• Color Doppler No flow at all – Flow around thrombus
• Differential dg Fresh thrombus vs very slow flow
Benign vs malignant thrombus
• CEUS Fresh flow: absence of flow
Very slow flow: presence of flow
Benign thrombus: no enhancement
Malignant thrombus: arterial enhancement
Piscaglia F, Sidhu P, Brabrand K and Borghi A
EFSUMB – European Course Book – Liver Transplantation – 2011.
67. Portal vein thrombosis
Echogenic thrombus in main PV with lack of color-filling
Sanyal R et al. Indian J Radiol Imag 2014 ; 24 : 360 – 366.
69. Diagnosis of malignant PV thrombosis
• “AASLD” guidelines1 PV > 23 mm in diameter
Arterial-like flow on Doppler
Increased serum α-FP
• Piscaglia criteria2 Mass-forming features of thrombus
Disruption of veins walls
Thrombus vascularization (US-CT-MRI)
• FNA CT- or US-guided
1 DeLeve L et al. Vascular disorders of the liver. Hepatology 2009 ; 49 : 1729 – 1764.
Piscaglia F et al. Liver transplantation 2010 ; 16 : 658 – 667.
70. Malignant PV thrombosis / CEUS
38 pts (15 benigns - 23 malignants) – Conclusive (37/38)
Dănilă M et al. Medical Ultrasonography 2011 ; 13 : 102 – 107.
Gray-scale US
Malignant PVT Arterial phase
Enhancement
Portal phase
Wash-out
Late phase
Wash-out
Contrast-Enhanced US
71. Malignant PV thrombosis
Piscaglia criteria
Piscaglia F et al. Liver transplantation 2010 ; 16 : 658 – 667.
Low-resistance pulsatile
arterial flow in thrombus
Thrombus occupying part of the left portal vein
Mass-forming features of thrombus
Disruption of veins walls
72. Doppler US of significant PV stenosis
• Color Doppler Aliasing at stenosis
• Pulsed Doppler PSV ˃ 1 m/s at stenosis
3 – 4 increase in velocity at stenosis
site compared to 2 cm upstream
Piscaglia F, Sidhu P, Brabrand K and Borghi A
EFSUMB – European Course Book – Liver Transplantation – 2011.
73. Portal vein stenosis
Color aliasing at vascular anastomosis
Sixfold velocity in poststenotic segment relative to prestenotic segment
Significant stenosis
Long axis of main portal vein
Crossin JD et al. RadioGraphics 2003; 23:1093 – 1114.
74. Portal venous gas in LT
• Causes Common transient finding in early postop period
Serious disease Bowel necrosis
Intra-abdominal abscess
Small-bowel obstruction
Sepsis
• Diagnosis CT scan
Doppler US Useful for PV gas detection
Does not necessarily indicate severe pathology
Abboud B et al. World J Gastroenterol 2009 August 7; 15(29): 3585 – 3590.
75. Portal vein gas
Acute trans-mural mesenteric infarction
Wiesner W et al. Radiology 2003 ; 226 : 635 – 650.
Intra-hepatic PV gas in periphery of both lobes
CECT scan
76. Portal vein gaz
Piscaglia F, Sidhu P, Brabrand K and Borghi A
EFSUMB – European Course Book – Liver Transplantation – 2011.
Bright areas in liver parenchyma
Accumulation of gas bubbles
Gray-scale US
Vertical bidirectional spikes
At laparotomy: bowel perforation
Spectral Doppler US
Doppler US is useful for detection of PV gas
78. Hepatic veins & IVC
Stenosis – Kinking – Thrombosis
• Causes Narrowing of anastomosis
Kinking of vessels
Transplant organ torsion (size mismatch)
• Manifestation Liver failure
Portal hypertension
Ascites & pleural effusion
• Biology Increase liver enzymes & bilirubin
Impairment of hepatic synthetic activities
Piscaglia F, Sidhu P, Brabrand K and Borghi A
EFSUMB – European Course Book – Liver Transplantation – 2011.
79. Doppler US of significant HV stenosis
• Color Doppler Aliasing at site of anastomosis
Flow reversal in IVC
• Pulsed Doppler Upstream Monophasic wave
PSV ˂ 15 – 20 cm/s
3 – 4 fold velocity increase at stenosis
site compared to few cm upstream
Piscaglia F, Sidhu P, Brabrand K and Borghi A
EFSUMB – European Course Book – Liver Transplantation – 2011.
Monophasic wave seen in absence of stenosis
Serial exams: new appearance of monophasic waveform
80. HV stenosis at piggyback site
Piscaglia F, Sidhu P, Brabrand K and Borghi A
EFSUMB – European Course Book – Liver Transplantation – 2011.
HV stenosis with aliasing Upstream anastomosis: flattened flow (14 cm/s)
Within piggyback: turbulent flow (100 cm/s)
81. IVC stenosis
End-to end IVC anastomosis
Crossin JD et al. RadioGraphics 2003; 23: 1093 – 1114.
Gray-scale US
Focal narrowing of
IVC lumen
Spectral Doppler US
Twofold velocity increase
between pre-stenotic &
post-stenotic segment
Turbulence at distal
IVC anastomosis
Color Doppler US
82. IVC thrombosis
Echogenic thrombus of RHV
extending into IVC
Subcostal oblique US Right paramedian sagittal US
IVC thrombus
Crossin JD et al. RadioGraphics 2003; 23: 1093 – 1114.
83. Doppler US in hepatic rejection
• Parenchymal texture irregularities not specific
Their presence may have several cause
• Doppler indices unreliable for diagnosis of rejection
Biopsy of transplanted liver required for diagnosis
of rejection
Piscaglia F, Sidhu P, Brabrand K and Borghi A
EFSUMB – European Course Book – Liver Transplantation – 2011.
86. Hepatic abscess
Crossin JD et al. RadioGraphics 2003; 23: 1093 – 1114.
Focal mass in left hepatic lobe
Highly echogenic air & dirty shadowing
Could be mistaken for gas in bowel
Transverse US image Corresponding CECT
87. Acute and sub-acute fluid collections
Crossin JD et al. RadioGraphics 2003; 23: 1093 – 1114.
Echogenicity similar to adjacent liver
Difficult to detect
Acute hematoma Sub-acute hematoma
Complex septated fluid collection
in hepatorenal space
88. Biloma after LDLT
Diagnosed by US guided aspiration
Hypoechoic collection in
right hepatic lobe
Tip of needle during US guided
aspiration
89. Hepatic infract
Echogenic focus with hypoechoic
rim in left hepatic lobe
Biopsy: hepatic infarct
Corresponding CECTMidline transverse US
Crossin JD et al. RadioGraphics 2003; 23: 1093 – 1114.
90. CBD stone
Dilated CBD
Echogenic calculus distal acoustic shadowing
Right para-median sagittal US
Crossin JD et al. RadioGraphics 2003; 23: 1093 – 1114.
91. Anastomotic stricture of bile duct
Corresponding ERCP
Normal waveform
Spectral Doppler of HA
CBD stenosis
Sagittal US
Crossin JD et al. RadioGraphics 2003; 23: 1093 – 1114.
CBD stenosis
92. Recurrent hepato-cellular carcinoma
Crossin JD et al. RadioGraphics 2003; 23: 1093 – 1114.
Median sagittal US Corresponding CECT
Large mass of mixed echogenicity
in right hepatic lobe
93. Post-transplant lympho-proliferative disease
Crossin JD et al. RadioGraphics 2003; 23:1093 – 1114.
Large heterogeneous mass
displacing porta hepatis
Biopsy: PTLPD
Transverse US image Contrast-enhanced CT
Mass encases vasculature
at porta hepatis
94. Recurrent sclerosing cholangitis
Right para-median sagittal US
Mural thickening of CBD
Magnified view
Crossin JD et al. RadioGraphics 2003; 23:1093 – 1114.
95. Adrenal hemorrhage
Crossin JD et al. RadioGraphics 2003; 23: 1093 – 1114.
Corresponding CECT
Hypoechoic nodule in hepatorenal space
Focal adrenal hemorrhage secondary to
intra-operative venous infarction
Transverse US image
Low-resistance profile: - Broad systolic peak
- Gradual deceleration from systole to diastole
- Well-maintained diastolic flow throughout the cardiac cycle.
Undulating:
Variation of PV diameter with inspiration:
Lack of caliber variation of the splenic and mesenteric vein during respiration is another parameter that has been investigated. In 1 study, this approach had a sensitivity of 80% and specificity of 100% in diagnosing portal hypertension. However, it is a method that has not gained widespread use, likely because of difficulties in measurement accuracy and interobserver variability.
PV velocity:
Significantly lower mean portal venous velocity was noted in cirrhotic patients (13 ± 3.2 cm/s versus 19.6 ± 2.6 cm/s in controls) by Zironi et al & 15 cm/s was considered as best cut-off value in detection of PHT, showing sensitivity & specificity of 88% and 96%, respectively.
51. Zironi G, Gaiani S, Fenyves D, et al. Value of measurement of mean portal flow velocity by Doppler flowmetry in the diagnosis of portal hypertension. J Hepatol 1992;16:298-303.
Triphasic waveform due to transmitted cardiac activity & Similar to waveform for the jugular vein.
Two negative waves and another positive wave.