Deborah J. Rubens, MD
Ultrasound of Liver Transplants
7/8/2015
DISCLOSURES
Ultrasound of Liver
Transplants
None
Deborah J. Rubens, M.D.
Professor of Imaging Sciences, Oncology and Biomedical
Engineering
University of Rochester Medical Center
Associate Director, Center for Biomedical Ultrasound
University of Rochester School of Medicine and Dentistry
OBJECTIVES
• Understand normal transplant
vasculature
• Distinguish abnormal Doppler
parameters as predictors of transplant
complications.
• Identify situations in which further
imaging (ie. CT, MR, Angiography) may
be useful to assess complications.
USA – Liver Transplantation 2009
Indications
• OLT – only treatment for irreversible acute liver
failure and chronic end-stage liver disease (ESLD)
• Guideline for liver transplant candidacy - based on
improved life expectancy with transplantation
• Priority - based on MELD score (bilirubin, creatinine,
INR)
• OUTCOMES (Expected per SRTR)
• Graft survival rates: 85%, 75% (1,3yr)
• Pt survival rates: 90%, 80% (1,3yr)
• Total OLT: >6.5K
• Pts on transplant waiting list: >16K
• Newly registered pts: >11K
www.seer.gov
www.srtr.org
SRTR data 2010-2012.
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Deborah J. Rubens, MD
Ultrasound of Liver Transplants
7/8/2015
LI 4.1 Total adult liver transplants
Liver Transplants: What are the
key vascular connections?
• Vascular
Anastamoses
– HA
– IVC
– PV
• Direct biliary
anastomosis vs
choledochojejunostomy
OPTN/SRTR 2011
annual report
NORMAL
PIGGYBACK
ANASTOMOSIS
LIMITS IVC TO ONE
CONNECTION
Imaging Protocol
• Grayscale liver and spleen, biliary tree,
perihepatic spaces
• Color and spectral Doppler
–
–
–
–
–
Post- operative Liver Transplant
Hepatic arteries: main, right and left
Portal vein: main, right and left
Hepatic veins: right and middle and left
Splenic vein
IVC
HEPATIC ARTERY
IMPORTANCE IN LIVER TXP
• Thrombosis or stenosis: 13%
• Major complication
Hepatic artery
thrombosis or
stenosis
• Less common
portal vein, hepatic
vein or IVC
stenosis or
thrombosis
• Leading cause of graft failure,
from bile duct necrosis,
infarction, abscess formation.*
• Dx in 10% of asx pts with
aggressive screening early
p/op **
• Rx: a. revision or re-txp
References:
*DeGaetano AM, Cotroneo AR, Maresca G, DiStasi C, Evangelisti R, Gui B, Agnes S. Journal of
Clinical Ultrasound, 28(8):373-80, 2000 October.
**Sakamoto Y, Harihara Y, Nakatsuka T, Kawarasaki H, Takayama T, Kubota K, Kimura W, et al.
The British Journal of Surgery, Volume 86(7), July 1999, pp. 886-889.
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Deborah J. Rubens, MD
Ultrasound of Liver Transplants
7/8/2015
DX OF HA THROMBOSIS/STENOSIS
HAS/HAT Disastrous
Complication
• Resistive index (RI) <.5
and/or acc time > .08sec in
any of vessels (M, R or L)
– 73-81% sensitivity for HA
T/HAS*, **
• False Positives:
– Small non-vis HA’s p/op
– Reperfusion injury with
shunting (high velocitiy/
normal acc time).
• False negatives:
– Rapid collateral formation.***
*Dodd GD, Memel DS, Zajko AB, Baron RL, Santaguida LA. Radiology 1994 192: 657-661.
**Platt JF, Yutzy GG, Bude RO, Ellis JH, Rubin JM. AJR 1997;168:473-476.
***Wolf R, Porte RJ, van der Vliet TM, Kok T. Journal of Clinical Ultrasound, 29(7):406-10, 2001 Sept.
Rising LFT’s Post–op Txp
Day 1Normal HA
Day 3-Wall
thump in HA
Low RI’s- HAS?
False Positive: Intraparenchymal Shunting
Post Operative Day 0
Post Operative Day 1
Abnormal LFT’s –HAS?
HAT with collateral flow
seen on US
Corresponding PTC shows
biliary necrosis
Adult LRD Right Lobe Allograft
HAT with Normal RIs
Saad WEA, Lin E, Ormanoski M, Darcy MD,
Rubens DJ. Noninvasive Imaging of Liver
Transplant Complications .Tech Vasc
Interventional Rad 10:191-206, 2007.
HA (arrowheads)
reconstituted from phrenic
artery collaterals (arrows)
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Deborah J. Rubens, MD
Ultrasound of Liver Transplants
7/8/2015
Spectral Doppler and RI’s First Ten
Days Post Op
Normal
(244/645)
37.8%
RI = 1
(210/645)
32.6%
RI < 0.5
(108/645)
16.7%
Absent HA
(83/645)
12.8%
Hedegard , Bhatt, Saad, Rubens, Dogra Hepatic arterial waveforms on early posttransplant Doppler
ultrasound. Ultrasound Q. 2011 Mar;27(1):49-54
Do High RI’s predict HAT?
Garcia-Criado, et al: Significance of and contributing factors for a high resistive index on Doppler sonography of the
hepatic artery immediately after surgery: prognostic implications for liver transplant recipients; AJR: 181(3): 831-8, Sept.
2003.
ABSENT DIASTOLIC FLOWUSUALLY RETURNS TO NORMAL
NO INCREASED INCIDENCE OF HAT
Spectral Waveforms of 56 Patients
with HAT Days 0-10
Nonvisualization of HA
9/108 (8.3%)
RI = 1
10/210 (4.8%)
Normal hepatic waveforms
11/244 (4.5%)
Hedegard , Bhatt, Saad, Rubens, Dogra Hepatic arterial waveforms on early posttransplant Doppler
ultrasound. Ultrasound Q. 2011 Mar;27(1):49-54
Management of Non-vis HA:
Rescan, CEUS, Angiography or OR?
Transient Nonvisualization
Rescan <24 hours
All HA’s present
4/52 (7.6%) HAT
Persistant Nonvisualization
One or more HA
22/31 (71.0%) HAT
Odds Ratio 30.00 (95% CI 8.15 to 105.65)
Hedegard , Bhatt, Saad, Rubens, Dogra Hepatic arterial waveforms on early posttransplant Doppler
ultrasound. Ultrasound Q. 2011 Mar;27(1):49-54
Day 1
Day 1
26/83 (31.3%)
Low RI < 0.5
Study 11/25 with no hepatic artery and abnormal
liver.
Initial study on 10/1 with high RI and
normal liver.
Day 14
Day 3
Hedegard , Bhatt, Saad, Rubens, Dogra Nonvisualization of Hepatic Arteries on Post-transplant Doppler
Ultrasound: Technical Limitation or Real?-RSNA 2008
IMPROVED HA VISUALIZATION
WITH US CONTRAST
• 8/72 no flow on CDUS
• 6 flow on CEUS
(Optison .5ml)
– confirmed with angio or
nl f/u US.
• 2 no flow, angiography
confirmed
• US sensitivity rose from
.91 to 1.0 (p<.014)
Benjamin K. Hom, BS, Ruchi Shrestha, MD, Suzanne L. Palmer, MD, Michael D. Katz, MD, R.
Rick Selby, MD, Zhanna Asatryan, BA, Jabali K. Wells, BS and Edward G. Grant, MD Prospective
Evaluation of Vascular Complications after Liver Transplantation: Comparison of
Conventional and Microbubble Contrast-enhanced US Radiology 2006;241:267-274
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Deborah J. Rubens, MD
Ultrasound of Liver Transplants
6 WEEKS POST ANGIOPLASTY
HAS?
Mha anastomotic stenosis
7/8/2015
balloon angioplasty
SELECTIVE HA
ARTERIOGRAM
STENT PLACED
ONE MONTH LATER
ONE MONTH
LATER
SIX MONTHS LATER
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Deborah J. Rubens, MD
Ultrasound of Liver Transplants
IVC AND HEPATIC VENOUS
OUTFLOW OBSTRUCTION
7/8/2015
IVC Thrombosis and
Stenosis
• Rare in cadaveric transplants (1.3%) due to
direct IVC-IVC anastomosis (1)
• Increased (6.7-16.6%) in live donors; small
hepatic veins anastomoses (2)
• Presentation: abd pain, ascites, poor liver fx
• Doppler dx: monophasic waveform (1,2)
• 10mm pressure gradient across stenosis
considered clinically significant (2,3)
(1) Rossi et al. Upper IVC Anastomotic Stenosis in Liver Transplant Recipients: Doppler US
Diganosis: Radiology 1993;187:387-389.
(2) Ko et al. Hepatic Vein Stenosis after Living Donor Liver Transplantation: Evaluation with Doppler
US Radiology 2003; 229: 806-810
(3) Ko et al. Endovascular Treatment of Hepatic Venous Outflow Obstruction after Living-donor
Liver Transplantation JVIR 2002; 13: 591-599
POST TRANSPLANT COMPLICATIONS IVC
POST TRANSPLANT
COMPLICATIONS:
HEPATIC VEINS
RHV dampened waveform on 2 separate
scans, however no relevant clinical symptoms
so no revision needed.
Symptomatic HV Stenosis
Elevated Hepatic Wedge Pressures
Required IVC Revision
Note 4:1 ratio of HV velocity at narrowed
area vs proximal intrahepatic velocity.
IVC STENOSIS
RELATED DONOR
Leg and abdomen swelling 3
years post txp . Treated over
15 months with multiple trials
of angioplasty, eventually
successfully stented.
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Deborah J. Rubens, MD
Ultrasound of Liver Transplants
7/8/2015
PORTAL VEIN THROMBOSIS
POST LIVER TRANSPLANT
INITIAL EXAMS NORMAL
PORTAL VEIN COMPLICATIONS
• Stenosis-common- usually asymptomatic.
• Thrombosis, relatively rare.
• HA-PV fistulae-common
– post traumatic, (liver biopsy)
– Doppler : low RI in feeding h a, arterialized
shunt flow in enlarged pv
– require embolization for sx (cardiac failure)
3 mo later
Rapidly deteriorating
liver fx, required
retransplantation
Redundant portal vein
predisposed to PV
thrombosis.
Portal Vein Stenosis
•
•
•
•
•
Day1
Usually at anastomosis
Angiographically stenosis = 8mm gradient
Stenotic velocity155 cm/sec (nl= 58cm/sec)*
3:1 ratio yields 73% sensitivity for stenosis*
Many resolve spontaneously over time
– (Grant et al 2009 RSNA)
Day 2
Day 3 post thrombectomy
*Chong, WK, Beland, JC, Weeks SM: Sonographic Evaluation of Venous
Obstruction in Liver Transplants AJR, June 1, 2007; 188(6): W515 - W521
PV Stenosis?
PORTAL VEIN STENOSIS?
Patient asymptomatic and ratio
normal, so no rx.
3 months later
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Deborah J. Rubens, MD
Ultrasound of Liver Transplants
PORTAL VEIN
STENOSIS
7/8/2015
Post Transplant Hepatic CT
Peak PV Vel >155 and ratio of 5:1
Post Stent
PORTAL VEIN THROMBOSIS?
No detectable flow in the MPV with reversed flow in R and LPVs? Doesn’t
make sense. What to do? Get a CT.
HEMATOMA COMPRESSES MPV
FOLLOWING DECOMPRESSION
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Deborah J. Rubens, MD
Ultrasound of Liver Transplants
7/8/2015
RHA TO PORTAL VEIN FISTULA
RIGHT HA-PV FISTULA
RPV
54 yr old man, 2 yrs post liver transplant with abnormal liver function.
HA- PV Fistula
• Common Complication
• Most Asymptomatic
• Seen in up to 50% of patients
within 1 week post biopsy
• Less than 10% persist beyond
a week
• Most close spontaneously
Saad WEA, Lin E, Ormanoski M, Darcy MD, Rubens DJ. Noninvasive Imaging of
Liver Transplant Complications .Tech Vasc Interventional Rad 10:191-206, 2007.
HA Pseudoaneurysms
•
•
•
•
•
Extrahepatic
Occur at anastomosis
Often missed at US
US 13% sensitivity
CTA 78%
Saad WEA, Lin E, Ormanoski M, Darcy MD,
Rubens DJ. Noninvasive Imaging of Liver
Transplant Complications .Tech Vasc
Interventional Rad 10:191-206, 2007.
Arterial Steal Syndromes
• ?Consequence of excess PV flow
• Dx by arteriography-low flow into allograft
• US shows elevated RI’s with low velocity or loss
of HA flow signal, loss of diastolic flow most
specific
• Angiography demonstrates increased flow to the
splenic a. or gastroduodenal a.
• Rx includes splenic artery embolization
Garcia-Criado AJR 2009;193(1):128–135
Sanyal and Shah JUM 2009:28:471-477
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Deborah J. Rubens, MD
Ultrasound of Liver Transplants
7/8/2015
Post Coiling
PV Steal
• Residual varices divert inflow from PV
• Cases C/O Mindy Horrow
Immediate
24 hours later
Poor portal vein flow post-operatively
Patient returned to OR
Large splenorenal varices shunted flow from PV
Ligation of varix improved PV flow
Despite revising anastomosis,
intraoperative flow is very poor
Day 1
Day 2
Horrow, etal. JUM 2010;29:125
5 months post transplant-
Portal Vein Thrombosis
Pre-operative imaging
Embolization of varices and thrombectomy of
portal vein re-establishes flow
large coronary varices
Acute thrombus
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Deborah J. Rubens, MD
Ultrasound of Liver Transplants
Conclusions
7/8/2015
THANK YOU
• Doppler US central to management of
hepatic transplants
• Critical for diagnosis of arterial and
venous thromboses and stenoses as
well as abnormal flow patterns
• Identifies post interventional sequelae
including arteriovenous fistulae and
pseudoaneurysms.
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