Document Detail


The impact of hepatic pressurization on liver shear wave speed estimates in constrained versus unconstrained conditions.
MedLine Citation:
PMID:  22170769     Owner:  NLM     Status:  MEDLINE    
Abstract/OtherAbstract:
Increased hepatic venous pressure can be observed in patients with advanced liver disease and congestive heart failure. This elevated portal pressure also leads to variation in acoustic radiation-force-derived shear wave-based liver stiffness estimates. These changes in stiffness metrics with hepatic interstitial pressure may confound stiffness-based predictions of liver fibrosis stage. The underlying mechanism for this observed stiffening behavior with pressurization is not well understood and is not explained with commonly used linear elastic mechanical models. An experiment was designed to determine whether the stiffness increase exhibited with hepatic pressurization results from a strain-dependent hyperelastic behavior. Six excised canine livers were subjected to variations in interstitial pressure through cannulation of the portal vein and closure of the hepatic artery and hepatic vein under constrained conditions (in which the liver was not free to expand) and unconstrained conditions. Radiation-force-derived shear wave speed estimates were obtained and correlated with pressure. Estimates of hepatic shear stiffness increased with changes in interstitial pressure over a physiologically relevant range of pressures (0-35 mmHg) from 1.5 to 3.5 m s(-1). These increases were observed only under conditions in which the liver was free to expand while pressurized. This behavior is consistent with hyperelastic nonlinear material models that could be used in the future to explore methods for estimating hepatic interstitial pressure noninvasively.
Authors:
V Rotemberg; M Palmeri; R Nightingale; N Rouze; K Nightingale
Related Documents :
17307439 - Prosthetic replacement of the ascending aorta increases wall tension in the residual ao...
19046649 - Aortic pulsatile distention in young healthy volunteers is asymmetric: analysis with ec...
10952649 - Kawasaki disease complicated by renal artery stenosis.
8733869 - Reduction of aneurysm pressure and wall stress after endovascular repair of abdominal a...
20947409 - The effect of vessel material properties and pulsatile wall motion on the fixation of a...
17150059 - Utility of static pressure ratio recording during angioplasty of arteriovenous graft st...
11434939 - Six-month comparison of bimatoprost once-daily and twice-daily with timolol twice-daily...
15875139 - Successful management of cesarean section in a patient with romano-ward syndrome using ...
17005059 - The effects of apparatus dead space on p(aco2) in patients receiving lung-protective ve...
Publication Detail:
Type:  Comparative Study; Journal Article; Research Support, N.I.H., Extramural     Date:  2011-12-14
Journal Detail:
Title:  Physics in medicine and biology     Volume:  57     ISSN:  1361-6560     ISO Abbreviation:  Phys Med Biol     Publication Date:  2012 Jan 
Date Detail:
Created Date:  2012-01-05     Completed Date:  2012-04-19     Revised Date:  2012-05-10    
Medline Journal Info:
Nlm Unique ID:  0401220     Medline TA:  Phys Med Biol     Country:  England    
Other Details:
Languages:  eng     Pagination:  329-41     Citation Subset:  IM    
Affiliation:
Duke University, Durham, NC 27708, USA. veronica.rotemberg@duke.edu
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Descriptor/Qualifier:
Animals
Biomechanics
Dogs
Elasticity
Liver / pathology*,  physiopathology*
Liver Diseases / pathology,  physiopathology
Mechanical Processes*
Organ Size
Venous Pressure
Grant Support
ID/Acronym/Agency:
R01 CA-142824/CA/NCI NIH HHS; R01 CA142824/CA/NCI NIH HHS; R01 EB-002132/EB/NIBIB NIH HHS; R01 EB002132/EB/NIBIB NIH HHS; T32 GM007171/GM/NIGMS NIH HHS; T32 GM007171/GM/NIGMS NIH HHS

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine


Previous Document:  Paranasal sinus and skull base fibro-osseous lesions: when is biopsy indicated for diagnosis?
Next Document:  Improving the performance of diffusion-weighted inner field-of-view echo-planar imaging based on 2D-...