Purpose: To investigate the capabilities of a modern pseudo-continuous arterial spin labeling (PCASL) technique for non-invasive assessment of the temporal and spatial distribution of the liver perfusion in healthy volunteers on a clinical MR system at 3T.
Materials And Methods: A 2D-PCASL multi-slice echo planar imaging sequence was adapted to the specific conditions in liver: a) labeling by PCASL was optimized to the flow characteristics in the portal vein, b) background suppression was applied for reduction of motion related artifacts, c) post labeling delays (PLDs) were varied over a large range (0.7-3.5s) in order to get better insight in the temporal and spatial distribution of tagged blood in the liver, and d) a special timed-breathing protocol was used allowing for recording of 16 to 18 label-control image pairs and a reference M0 image for each of 4 to 6 slices within approx. 5min for one PLD.
Results: Measurements with multiple PLDs showed dominating perfusion signal in macroscopic blood vessels for PLDs up to 1.5 s, whereas pure liver parenchyma revealed maximum perfusion signal for a PLD of approx. 2 s, and detectable signal up to PLDs of 3.5 s. Data fitting to a perfusion model for liver provided a mean global perfusion of 153±15ml/100g/min and a mean transit time of 1938±332ms in liver parenchyma. Measurements with a single PLD of 2 s demonstrated that portal-venous and arterial perfusion components can be measured separately by two measurements with two different positions of the labeling plane (one for labeling of the global hepatopetal blood flow and one for selective labeling of the portal blood flow only). Relative contribution of blood from the hepatic artery to the global liver perfusion, the hepatic perfusion index (HPI), amounted to approx. 23%.
Conclusion: Modern and adapted protocols for assessment of liver perfusion by PCASL have the potential to provide perfusion and blood transit time maps in reasonable acquisition time.
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http://dx.doi.org/10.1016/j.zemedi.2018.08.004 | DOI Listing |
J Clin Med
December 2024
Department of General, Visceral and Transplantation Surgery, LMU University Hospital, LMU Munich, Marchioninistr. 15, 81377 Munich, Germany.
Hypothermic oxygenated machine perfusion (HOPE) has emerged as a critical innovation in liver transplantation (LTx), offering significant protection against ischemia-reperfusion injury (IRI). This study focuses on quantifying and characterizing immune cells flushed out during HOPE to explore its effects on graft function and post-transplant outcomes. Fifty liver grafts underwent end-ischemic HOPE.
View Article and Find Full Text PDFFood Chem Toxicol
January 2025
INSERM, Univ Rennes, INRAE, Institut NUMECAN (Nutrition, Métabolismes et Cancer) UMR_A 1341, UMR_S 1317, F-35000, Rennes, France; Laboratoire de toxicologie biologique et Médico-légale, CHU Rennes, Rennes, France.
Objective: Recently, the pig liver model perfused ex vivo using a normothermic machine perfusion (NMP) has been proposed as a suitable model to study xenobiotic metabolism and biliary excretion. The aim of our study is to describe the metabolism of NPS such as cathinones (with a focus on 4-Cl-PVP and eutylone) in blood and bile, using a normothermic perfused pig liver model.
Methods: Livers (n = 4) from male large white pigs, 3-4 months of age and weighing approximately 75-80 kg, were harvested and reperfused onto an NMP (LiverAssist®, XVIVO) using autologous whole blood at 38 °C.
Liver Transpl
January 2025
Abdominal Center Department, Istituto di Ricovero e Cura a Carattere Scientifico-Istituto Mediterraneo per i Trapianti e Terapie ad alta specializzazione (IRCCS ISMETT), University of Pittsburgh Medical Center Italy (UPMCI), Palermo, Italy.
Indian J Nucl Med
November 2024
Department of Nuclear Medicine, All India Institute of Medical Sciences, Rishikesh, Uttarakhand, India.
Hepatopulmonary syndrome (HPS) is a rare pulmonary vascular complication of chronic liver disease characterized by dilatation of pulmonary capillaries leading to vascular shunting and systemic hypoxemia. Diagnosis of HPS requires documentation of intrapulmonary vasodilation (IPVD), the two most common imaging studies performed for the detection of IPVD include transthoracic contrast echocardiography (TTCE) and 99m-Tc-macroaggregated albumin scintigraphy (99mTc-MAA scan). TTCE has high sensitivity and thus, is the preferred initial investigation, while 99mTc-MAA scan is highly specific and plays an adjuvant role in diagnosis.
View Article and Find Full Text PDFSci Rep
January 2025
Center for Engineering in Medicine and Surgery, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA.
Static cold storage of donor livers at 4 °C incompletely arrests metabolism, ultimately leading to decreases in ATP levels, oxidative stress, cell death, and organ failure. Hydrogen Sulfide (HS) is an endogenously produced gas, previously demonstrated to reduce oxidative stress, reduce ATP depletion, and protect from ischemia and reperfusion injury. HS is difficult to administer due to its rapid release curve, resulting in cellular death at high concentrations.
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