Suresh Anand Sadananthan, Mya Thway Tint, Navin Michael, Kuan Jin Lee, Lynette Shek, Yap Fabian, Keith Godfrey, Melvin Leow, Yung Seng Lee, Michael Kramer, Peter Gluckman, Yap Seng Chong, Christiani Jeyakumar Henry, Marielle Fortier, S. Sendhil Velan

In this study, we used MR-based estimation of abdominal fat distribution and the degree of adipocyte hypertrophy to study sex and ethnic differences in 4.5-year-old Asian children. Our results show sexual dimorphism in abdominal fat distribution in preschool children. Girls had higher subcutaneous fat depot volumes and lower adipose tissue hydration than boys. We also found that at 4.5 years, both deep and superficial subcutaneous fat volumes in Indian children were higher, while the ethnic difference in internal fat was non-significant. These differences may help explain why Indians are more susceptible to metabolic and cardiovascular diseases.

Navin Michael, Varsha Gupta, Suresh Anand Sadananthan, Aparna Sampathkumar, Li Chen, Hong Pan, Mya Thway Tint, Kuan Jin Lee, Lynette Shek, Yap Fabian, Keith Godfrey, Melvin Leow, Yung Seng Lee, Michael Kramer, Yap Seng Chong, Christiani Jeyakumar Henry, Marielle Fortier, Peter Gluckman, Neerja Karnani, S. Sendhil Velan

A large intramyocellular lipid (IMCL) pool is associated with early pathogenesis of insulin resistance and type 2 diabetes. Studies from mother-offspring cohorts indicate that, like obesity and metabolic traits, IMCL is also highly heritable. However, here have been not many studies on the effect of genetic variation on IMCL. Although a number of genome-wide association studies (GWAS) have established associations between several genetic loci and metabolic disorders, it is not yet known if these loci also contribute to IMCL levels, and help explain ethnic difference in IMCL levels. In this study, we examined the ethnic differences (Indian, Malay and Chinese) in IMCL in Singaporean children and the genetic risk variant(s) associated with these differences.

Sanjay Kumar Verma, Jadegoud Yaligar, Navin Michael, Tian Xianfeng, Venkatesh Gopalan, Suresh Anand Sadananthan, Rengaraj Ananthraj, S. Sendhil Velan

Non-Invasive Imaging of Brown Adipose Tissue is of significant interest due to its potential to combat obesity and diabetes. In this study, we have utilized diffusion spectroscopy to estimate the droplet size distribution in chow and high-fat diet fed brown adipose tissues obtained from rodents. The high-fat diet BAT exhibited reduction in the restriction due to the increase in droplet size. The histology results confirm the droplet size distribution in both control and high-fat diet tissues.

Rosa Tamara Branca, Andrew McCallister, Hong Yuan, Le Zhang, Alex Burant, Michael Antonacci

Despite histological evidence that all humans have brown adipose tissue, the detection of this tissue in overweight and obese subjects has proven to be a challenge. Here we demonstrate the combined used of hyperpolarized xenon gas (HP129Xe) MRI and xenon enhanced CT for the detection of BAT thermogenic activity and mass in lean and obese mouse phenotypes as well as our preliminary results in healthy young volunteers.

Maj Hedehus, Mark Chen, Jose Zavala-Solorio, Lance Kates, Oded Foreman, Junichiro Sonoda, Richard Carano

Anti-FGFR1/KLB is a novel experimental therapy to treat metabolic disorders and reverse lipid accumulation in the liver.  MRI estimates of proton density fat fraction demonstrated a dose-dependent anti-FGFR1/KLB treatment effect in a murine model of NAFLD.

Daniela Franz, Dominik Weidlich, Friedemann Freitag, Christina Holzapfel, Thomas Baum, Holger Eggers, Ernst Rummeny, Hans Hauner, Dimitrios Karampinos

Proton density fat fraction (PDFF) mapping has been emerging as important metabolic phenotyping parameter in obesity enabling spatially-resolved fat quantification in multiple organs. PDFF of adipose tissue has also recently gained significant attention due to the interest in developing biomarkers of brown fat which is assumed to be present in the adult supraclavicular fossa. However, it remains unknown how adipose tissue PDFF relates to other fat depots and anthropometric parameters. The present study aims to investigate the relationship of the supraclavicular and gluteal fat PDFF with SAT and VAT volumes and anthropometric obesity markers.

Junjie Ren, Shengzhang Ji, Chunxia Li, Zhizheng Zhuo, Hao Wang

Till now the type 2 diabetes (T2DM) is more and more prevalent, and diabetic nephropathy (DN) has become the main leading cause of end-stage renal disease (ESRD). However the onset of DN is always ambiguous. In recent years, many studies focused on the change of renal oxygenation in diabetes and showed renal hypoxia especially in medulla. Blood oxygen level dependent magnetic resonance imaging (BOLD-MRI) is a non-invasive method that can assess hypoxia in prostate gland by utilizing the endogenous contrast generated by paramagnetic deoxyhemoglobin.
 

Jonathan Andersson, Emma Kjellberg, Elin Lundström, Mathias Engström, Josefine Roswall, Stefan Bergman, Pär-Arne Svensson, Håkan Ahlström, Jovanna Dahlgren, Joel Kullberg

The purpose of this study was to characterize and compare brown and white adipose tissue in 7 year-old overweight/obese and normal weight children using whole-body water-fat MRI. Correlations were also performed between the brown adipose tissue measurements and other measurements, such as VAT and SAT volumes. Results overall showed expected differences and associations to several measures relevant for obesity. We conclude that whole-body water-fat MRI of 7 year-old children is feasible and allows characterization of brown and white adipose tissue. 

Wang Zhening, Liang Jiahao, Huang Yao, Ma Changchun, Wu Renhua, Yang Jurong, Liu Xingmu, Lin Yan

After our fecal metabonomic study of colorectal cancer (CRC) patients recently published in Oncotarget , we profiled urine metabolites from the same group of CRC patients, 40 age-matched healthy controls (HC), 18 esophageal cancers (EC), using proton nuclear magnetic resonance spectroscopy in conjunction with a multivariate statistics technique. OPLS-DA revealed that each stage of CRC could be clearly distinguished from HC and EC based on their different metabolomic profiles. These altered urine metabolites of CRC patients from HC potentially involved in the disrupted common pathways, and the different metabolites in CRC compare to EC indicated the special of the CRC.

Ronald Ouwerkerk, Aaron Cypess, Kong Chen, Peter Herscovitch, Robert Brychta, Brooks Leitner, Ahmed Gharib

¹H-MRS was used to measure relaxation properties, lipid peak ratios and water content of white adipose tissue (WAT) and brown adipose tissue (BAT) in humans with the aim of providing information that can be used to improve MRI based methods for identifying BAT.

Terence Jones, Sarah Wayte, Narendra Reddy, Oludolapo Adesanya, Thomas Barber, Charles Hutchinson

Lower fat content within brown adipose tissue (BAT) compared to white adipose tissue (WAT) has been exploited using Dixon-based MRI imaging methods to visualize BAT but is subject to inter-rater variability. To determine the optimal fat fraction threshold for identifying BAT, receiver operating characteristic (ROC) analyses of fat fraction maps derived from 3 point IDEAL MRI scans were performed for sixteen subjects.

This method had good-to-excellent accuracy in four cases, and fair accuracy in two, but failed in ten. A single universal cut-off point to differentiate BAT and WAT could not be identified, instead the optimal thresholds varied between individuals.

Alison Sleigh, Ajay Thankamony, Albert Koulman, Vlada Bokii, Graham Kemp, Leanne Hodson, David Dunger

We have investigated the response of different fat deposits to a 28 h fast in healthy nonobese males and shown significant increases in CH₂ IMCL in both the soleus and tibialis anterior muscles, and significant decreases in subcutaneous fat. Increases in TA and SOL IMCL correlated with oleic and palmitic acid FFA concentrations respectively. The compositional change of IMCL during the fast related inversely to the baseline composition, suggesting a selective efflux of unsaturated shorter chain IMCLs for preferential oxidation, which is in agreement with rat biopsy data, and supportive of the idea of IMCL as a flexible lipid store.

Kyu-Ho Song, Song-I Lim, Min Young Lee, Chi-Hyeon Yoo, Bo-Young Choe

Non-alcoholic steatohepatitis (NASH) is associated with metabolic syndrome as a result of insulin resistance and the accumulation of lipid droplets within hepatocytes. There is a need to diagnose and to accurately assess the progressive severity of hepatic steatosis with non-invasive biomarkers that are distinguishable from those in non-alcoholic fatty liver disease (NAFLD). Our findings demonstrate that fatty acid metabolism (saturated- and unsaturated-fatty acids) of hepatic steatosis induced by a methionine-choline diet can be distinguished from progressive NAFLD by using high-resolution magnetic resonance spectroscopy (MRS).

Venkatesh Gopalan, Jadegoud Yaligar, Sanjay Kumar Verma, Suresh Anand Sadananthan, Anna Ulyanova, Navin Michael, Anantharaj Rengaraj, Tian Xianfeng, S. Sendhil Velan

Exercise is an important intervention for correction of irregular fat-partitioning and treatment of metabolic dysfunction. There is a large interest in development of non-invasive methods for activation of brown adipose tissue (BAT) due to its potential to combat obesity. In this study we have investigated exercise induced BAT activation and IMCL from skeletal muscle of rodents fed with control and high fat diet. Our results show that exercise modulates the brown fat with reduction in fat fraction, increased UCP1 expression and reduction in “white” like adipocytes in control and high fat diet fed rats.

Venkatesh Gopalan, Sanjay Kumar Verma, Jadegoud Yaligar, Anantharaj Rengaraj, Tian Xianfeng, Bhanu Prakash K N, Suresh Anand Sadananthan, Navin Michael, S. Sendhil Velan

There is a global interest in healthy aging and also to avoid metabolic dysfunction.   BAT and WAT play an important role in modulating the energy expenditure.   In this study we have investigated the interscapular BAT and abdominal adipose tissues in young and old rats.  During aging the iBAT activity is reduced due to the increase in “white” like adipocytes.  The abdominal adipose tissues including VAT and SAT show increase in adipocyte size resulting in hypertrophy. Modulating these fat depots with nutritional interventions is of significant clinical interest.

Nicolas Linder, Alexander Schaudinn, Nikita Garnov, Roland Stange, Kilian Solty, Thomas Rakete, Nora Dipper, Sophia Michel, Thomas Karlas, Matthias Blüher, Stefanie Lehmann, Andreas Oberbach, Rima Chakaroun, Thomas Kahn, Harald Busse

The last decades have seen an increasing socioeconomic impact of obesity and obesity-related diseases. Noninvasive measures like subcutaneous and visceral adipose tissue (SAT, VAT) amounts and are also increasingly correlated with other, often clinical or metabolic findings as well as independent patient characteristics, even interventional complication rates. MRI fat quantification is common but manual processing is often laborious and time consuming while fully automatic segmentation is prone to errors. This work takes a custom-made semiautomatic MRI tool and prospectively analyzes the processing and interaction times for readers with different experience as well as patients from different BMI groups. 

Satoshi Goshima, Kimihiro Kajita, Tomoyuki Okuaki, Keita Fujimoto, Shoma Nagata, Yoshifumi Noda, Hiroshi Kawada, Nobuyuki Kawai, Hiromi Koyasu, Masayuki Matsuo

We successfully quantified fatty acid composition in the liver, subcutaneous, and visceral fat tissue using modified Dixon technique with flexible six echo times and seven-peak spectral model with lipid components. Our results suggested that fatty acid composition of depot fat was varied among the patients with different metabolic status. We also demonstrated the possible relationship of unsaturated fatty acid in depot fat to cholesterol level and insulin tolerance.

Alessandra Bierwagen, Daria Caspari, Maik Rothe, Klaus Straßburger, Jong-Hee Hwang, Michael Roden, Regina Ensenauer

This study assessed energy and fat metabolism in a well phenotyped cohort of patients with organic acidemias using non-invasive MR spectroscopy. ³¹P and ¹H spectra of the liver as well as ¹H spectra of the muscle were acquired in 27 patients and 30 healthy controls (age-, sex-, BMI-matched). We found higher liver fat content in patients with propionic acidemia. The level of creatine in the soleus muscle was higher in patients with methylmalonic acidemia and propionic acidemia. In conclusion, the results provide evidence for previously unknown abnormalities of liver fat and muscle energy metabolism in patients with organic acidemias.

Yu Xin Yang, Wee Shiong Lim, Mei Sian Chong, Laura Tay, Suzanne Yew, Audrey Yeo, Cher Heng Tan

The demand for measurements of fat quantities is driven by the rising prevalence of sarcopenia and sarcopenic obesity (SO). In order to reduce the time and the cost of image processing, several studies have estimated the subcutaneous fat (SF) and visceral fat (VF) volume from a single slice. However, the population of studies may not have necessarily included patients with either sarcopenia or SO. This study aims to determine the correlation between the cross-sectional areas in a single slice at different vertebra levels and the volumes of SF and VF in the abdomen for sarcopenic and SO populations using MRI.

Amanda MacCannell, Kevin Sinclair , Lannete Friesen-Waldner, Charles McKenzie, James Staples

Hibernating mammals use brown adipose tissue (BAT) as a primary source of heat production. Volumes of both white adipose tissue (WAT) and BAT increase in the autumn even when temperatures are warm. Between Aug 19th and Oct 13th we used water-fat MRI to measure the dynamics of BAT and white adipose tissue as ground squirrels prepared for hibernation under either cold or thermoneutral temperatures. We found that the volume of a tissue that resembles BAT around the eye, increased significantly in cold exposed animals to warm exposed in October, as the animals are preparing for winter.

Rui Wang, Zhiyong Lin, Xueqing Sui, Kai Zhao, Feng Wei

Our study was to investigate the feasibility of using blood oxygen level dependent (BOLD), oxygen extraction fraction (OEF) and arterial spin labeling (ASL) techniques for the detection of renal hemodynamics and oxygenation changes in rabbits with diabetic nephropathy (DN).

Stephen Bawden, Jack Sargeant, Liz Simpson, Mehri Kaviani, Myra Nimmo, Penny Gowland, Ian MacDonald, James King, Guruprasad Aithal

In this study, 9 obese male participants underwent 6 weeks of sprint interval training (SIT) and changes in visceral, subcutaneous and intra-hepatocellular fat were measured using MRI and MRS at baseline, control (>4 weeks later) and post exercise. Change in liver lipid composition was also assessed.

Manil Chouhan, Tim Bray, John Connell, Jane MacNaughtan, Alan Bainbridge, Helen Jones, Abeba Habtieson, Nathan Davies, Rajiv Jalan, Shonit Punwani, Tammy Kalber, Mark Lythgoe, Margaret Hall-Craggs, Rajeshwar Mookerjee, Stuart Taylor

There is a growing interest in the development of new animal models of non-alcoholic fatty liver disease.  In this study, we use T1, proton density fat fraction (PDFF) and R2* mapping to characterise hepatic parenchymal tissue and the evolution of MR properties over time in a high-fat, high-cholesterol diet model of fatty liver disease.

Curtis Wiens, Cristobal Arrieta, Ignacio Osorio, Ben Ratliff, Timothy Colgan, Alan McMillan, Nathan Artz, Luke Funk, Guilherme Campos, Jacob Greenberg, Daniela Esparza, Sergio Uribe, Claude Sirlin, Scott Reeder

This work monitored longitudinal changes in visceral (VAT) and subcutaneous (SCAT) adipose tissue in response to weight loss.  Twenty-one patients undergoing clinical weight loss surgery (WLS) were recruited for 5 MRI studies: 2-3 weeks prior, 1 day prior to WLS and 1, 3, and 6 months post-WLS. Single breath-hold, chemical shift encoded acquisitions were analyzed using an Osirix semi-automated segmentation software to monitor changes in VAT and SCAT volumes.  Continual reductions in VAT and SCAT were measured over the five visits.  At every visit, each patient’s relative body fat distribution remained relatively constant despite overall reductions in both VAT and SCAT.

Alessandra Borgheresi, Davinia Ryan, Simone Krebs, Sarah Eskreis-Winkler, Lorenzo Mannelli

Chemotherapy is hepatotoxic. Since steatosis is an early sign of hepatotoxicity, an accurate estimation of the changing of fat liver concentration would be useful in the management of oncologic patients. The purpose of this study was to compare fat liver concentration estimated by T1-weightened-in-and-out-of-phase (IOP) imaging with the one obtained by IDEAL-IQ method in an oncologic patients population with unknown liver iron concentration. A statistical difference was demonstrated between fat fraction estimated with conventional IOP imaging and IDEAL-IQ method.

Yoshihiko Fukukura, Yuichi Kumagae, Hiroto Hakamada, Koji Takumi, Kiyohisa Kamimura, Masanoari Nakajo, Tomoyuki Okuaki, Takashi Yoshiura

We compared directly acquired diffusion-weighted imaging (DWI) at b-values of 1500 s/mm² and 2000 s/mm² with computed DWI (cDWI) at the same b-values, which was calculated from directly acquired DWI data at b-values of 0 s/mm² and 1000 s/mm². Our main result is that the incidence of clear hyperintense pancreatic adenocarcinomas was significantly higher on cDWI at a b-value of 1500 s/mm² than on directly acquired DWI at a b-value of 1000 s/mm² (P < 0.001) and was comparable to the incidence on directly acquired DWI at a b-value of 1500 s/mm², suggesting that cDWI to a b-value of 1500 s/mm² has diagnostic merit.

Uffe Kjærgaard, Christoffer Laustsen, Thomas Nørlinger, Emmeli Mikkelsen, Rasmus Tougaard, Qi Haiyun, Lotte Bertelsen, Niels Jessen, Hans Stødkilde-Jørgensen

Hepatic regulation of glucose homeostasis is of pivotal importance and thus in vivo interrogation of hepatic energetic alterations in disease and treatment non-invasively using [1-13C] pyruvate has been proposed as a novel modality for assessing metabolic status. Here we investigated the metabolic effect of a glucose challenge on the porcine liver. A hepatic metabolic shift towards a reduced gluconeogenesis (increased lactate pool size) was observed following the glucose challenge, confirming hyperpolarized 13C MR’s ability to detect such changes. These findings support the use of hyperpolarized MR in metabolic challenge test in patients. 

Zixin Deng, Wensha Yang, Jianing Pang, Richard Tuli, Behrooz Hakimian, Robert Reznik, Xiaoming Bi, Benedick Fraass, Debiao Li, Zhaoyang Fan

Stereotactic body radiation therapy with a simultaneous integrated boost (SBRT-SIB) has been used to improve tumor resection rate by sterilizing cancerous tissue that are surrounding the vessels. Accurate tumor imaging and tumor motion assessment will enhance the potential for SBRT-SIB. 4D-MRI (respiratory resolved, 3D volumetric images) has emerged as a promising imaging technique for characterizing tumor motion due to the absence of ionizing radiation and its superior soft tissue contrast. This study explored a slab-selective excitation approach to increase the blood vessel to tissue contrast with the goal of improving the accuracy of boost volume definition in radiation therapy.

Bang-Bin Chen, Yu-Wen Tien, Ming-Chu Chang, Mei-Fang Cheng, Shih-Hung Yang, Tiffany Ting-Fang Shih

The purpose of this study is to evaluate the association of imaging biomarkers from PET/MR with overall survival in pancreatic cancer patients. Sixty-four patients with pathologically-proven pancreatic adenocarcinoma underwent PET/MRI before treatment. The imaging biomarkers included Ktrans and Peak from DCE-MRI, minimal apparent diffusion coefficient from DWI, choline from MR spectroscopy, standard uptake values, metabolic tumor volume, and total lesion glycolysis of the tumors. Among all imaging parameters, Peak was found to be an independent predictor for overall survival in these patients. Thus, the imaging biomarkers from PET/MRI reflect different tumor characteristics and may predict survival outcome in these patients.

Shannon Donnola, Kimberly McBennett, David Weaver, Lan Lu, Xin Yu, James Chmiel, Michael Konstan, Mitchell Drumm, Chris Flask

Liver disease is the third leading cause of death in Cystic Fibrosis (CF). Unfortunately, conventional liver function tests cannot sensitively detect it.^1-3 Liver stiffness measurements via MRI and ultrasound have shown promise but are unfortunately impacted by other factors (e.g., hepatic fat) potentially resulting in over-estimation of fibrosis.^4,5 We recently validated a T1-MRI assessment of biliary dilatation and fibrosis in a rat model of congenital hepatic fibrosis (Figs. 1-3).⁶ In this clinical study, we show that T1-MRI can be used to sensitively detect increased percent bile duct volumes in CF patients in comparison to control subjects with normal liver function. 

Gaelle Diserens, Roland Kreis, Dino Kroell, Philipp Nett, Guido Stirnimann, Peter Vermathen, Reiner Wiest

Bile exerts multiple functions in the liver and gut with a crucial role for triglyceride-, sterol- and carbohydrate-metabolism and is a key player in disease processes. The study purpose was to develop a reliable MRS protocol and to assess variability of bile acid determination in human gallbladder. Our study demonstrated higher stability and reliability of gallbladder spectra with subjects measured  in prone position compared to back position. Relatively small coefficients of variation were obtained in a reproducibility study particularly within subjects, suggesting clinical applicability of the method, especially for longitudinal studies.

Nikhar Kinger, Peter Harri, Lauren Alexander, Courtney Moreno, Pardeep Mittal

Wide spectrum of hepatobiliary and pancreatic diseases can lead to development of benign and malignant biliary strictures such as cholangiocarcinoma, pancreatic adenocarcinoma, ampullary carcinoma, PSC, autoimmune pancreatitis, ischemic strictures, post cholecystectomy, trauma etc. MRI characteristic of malignant strictures such as length, location, wall thickness, asymmetry, luminal regularity and enhancement will be discussed. CE_MRI helps to reach specific diagnosis and narrow differential diagnosis which is important for management and treatment planning

Yu Shi, qiyong guo, yin liu, yanqing liu

An accurate early diagnosis(<24h of admission) of acute pancreatitis is clinically important. Our work shows that MR elastography has significantly better diagnostic performance for detecting AP than that achieved using the conventional CT/MR imaging, with improved sensitivity and accuracy. Early MRE is a promising technique to diagnose AP in a noninvasive fashion on admission.

Soudabeh Fazeli Dehkordy, Saya Igarashi, Carolina Lamas Constantino, Jonathan Hooker, Cheng Hong, Adrija Mamidipalli, Alan Hemming, Claude Sirlin

Gadoxetate-disodium (Gd-EOB-DTPA)-enhanced 3D T1- weighted (T1W) MR cholangiography (MRC) is recognized as an efficient method for evaluation of biliary anatomy, which is critical in the preoperative evaluation of living liver donors. We hypothesize that bile duct visualization could be improved by acquiring Gd-EOB-DTPA-enhanced T1W multi-echo (ME) gradient-echo (GRE) images and generating parametric R2* map cholangiograms. In 10 liver donor candidates, we retrospectively compared biliary duct visualization on T1W-R2* maps vs. 3D T1W cholangiograms obtained 20 minutes after IV administration of gadoxetate disodium. T1W-R2* maps provided comparable visualization of the first-order bile duct branches and better visualization of the second-order branches (p<0.05).

Puneet Sharma, Xiaodong Zhong, Marcel Nickel, Hiroumi Kitajima, Pardeep Mittal

This investigation evaluates the performance and accuracy of a fast inversion recovery Look-Locker method for in vivo liver T1 mapping. Several parameters were assessed using T1 phantoms to describe accuracy trends and prevalence for artifacts. The method was also applied in vivo to demonstrate feasibility of fast T1 mapping of liver parenchyma and blood pool. The results offer insight into optimal imaging parameters, and showed good agreement with known T1 values at 1.5T.

Huimin Lin, Weibo Chen, Li Jiang, Lyu Li, Ruokun Li, Fuhua Yan

The purpose is to implement high resolution black blood T2-weighted TSE liver imaging in order to facilitate focal liver lesion detection and characterization. DANTE black blood preparation module, T2 weighted Multivane XD multi-slice acquisition and respiratory trigger were combined together. 8 healthy volunteers underwent MRI scanning on 3T Ingenia MR Syste. The black blood T2-weighted sequence showed high image quality and no artifacts. Hepatic veins, portal vein and their main branches were all suppressed successfully. No significant difference was shown in the SNR between black blood and routine T2-weighted images. In conclusion, the black blood T2-weighted imaging could provide robust and good imaging quality.

Chen-Te Chou, Ran-Chou Chen

The purpose of our study was to investigate the relationship between splenic MR elastography (MRE) and liver fibrosis stages. 109 patients underwent histological examination and abdominal MR examination within 3-months interval were enrolled in our study. MRE was performed with passive driver on right and left chest wall separately. The mean stiffness value of liver and spleen was determined and showed good correlation between hepatic/splenic stiffness and liver fibrosis stage. Our results demonstrated that spleen stiffness measured by MRE was significant correlated with liver fibrosis stage. Combination of the spleen/liver stiffness provide higher diagnostic value than liver stiffness alone.

Yoshifumi Noda, Satoshi Goshima, Tomoyuki Okuaki, Kimihiro Kajta, Hiroshi Kawada, Nobuyuki Kawai, Hiromi Koyasu, Masayuki Matsuo

The hepatocyte fraction (HeF) is based on simple pharmacokinetics and can quantitatively estimate the fraction of hepatocyte. In our study, the HeF, quantitative liver-to-spleen contrast ratio (Q-LSC), and delta T1 value were compared and correlated with Child-Pugh and MELD score. The HeF demonstrated the highest correlations with Child-Pugh score (r = -0.58, P < 0.0001) and MELD score (r = -0.57, P < 0.0001). The HeF could be a useful biomarker for the evaluation of liver function, compared to conventional imaging based quantitative methods.

Manil Chouhan, Alex Menys, Alan Bainbridge, David Atkinson, Shonit Punwani, Rajeshwar Mookerjee, Stuart Taylor

Liver stiffness measured with elastography has useful clinical applications but requires the use of expensive, specialist equipment.  In this study, we acquire dynamic ‘cine’ data of the liver to capture cardiac-induced liver motion during cardiac cine MRI.  We quantify these data by applying a registration algorithm and use the deformation fields as a surrogate for liver stiffness. We demonstrate feasibility and good seven-day reproducibility and evaluate the effects of physiological haemodynamic changes using a liquid meal challenge. This technique would be widely applicable to hospital MRI scanners without elastography equipment. 

Lucian Purvis, William Clarke, Ladislav Valkovic, Christina Levick, Michael Pavlides, Eleanor Barnes, Jeremy Cobbold, Stefan Neubauer, Matthew Robson, Christopher Rodgers

Phosphorus (³¹P) metabolites have potential value as markers in liver disease. The increase in field strength from 3 to 7T allows more accurate quantitation of the liver ³¹P-MRS spectrum. Ten volunteers and eleven patients with liver cirrhosis were scanned using a 16-channel array and a 3D UTE-CSI sequence. Metabolite concentrations were calculated using an endogenous 2.5mM ATP reference. Significant reductions in inorganic phosphate and phosphoenolpyruvate/phosphatidylcholine concentrations were seen, as well as an increase in glycerophosphoethanolamine (P<0.05). The splitting of PDE into its constituent peaks allows more insight into changes in metabolism.

Xueqin Zhang, Jian Lu, Tao Zhang, Jifeng Jiang, Ding Ding, Sheng Du, Weibo Chen

The purpose of this study was to investigate the ability of T1 mapping on Gd-EOB-DTPA-enhanced MRI for the assessment of liver function of HBV-induced cirrhosis. We used Look-Locker sequences to acquire T1 mapping images pre and post-contrast at 5, 10, 15 and 20 minutes after Gd-EOB-DTPA administration, T1 relaxation times of the liver parenchyma were measured, reduction rates of T1 relaxation times between pre- and post-contrast enhancement were calculated, our study showed that Gd-EOB-DTPA-enhanced T1mapping MRI is useful for the evaluation of Liver function of HBV-induced cirrhosis.

Aaryani Tipirneni-Sajja, Ruitian Song, M. Beth McCarville, Ralf Loeffler, Jane Hankins, Claudia Hillenbrand

Extraction of liver parenchyma is an important step in the evaluation of R2*-based hepatic iron content. Traditionally this is performed by radiologists via thresholding, an iterative, time consuming process susceptible to interrater variability. Here, a new method based on Frangi vesselness filtering is presented that automatically removes hepatic vessels from liver tissue, thereby reducing potential bias and improving workflow. The method was evaluated in digital liver phantoms and 42 iron overloaded patients. Excellent agreement between manual and automated liver parenchyma segmentation was found which demonstrates accuracy and robustness of the proposed method. 

Kelly Tung, Alvin Silva, Marcela Salomao, Christine Menias, Christine Zwart, Sukhdeep Singh, Amy Hara

Hepatocellular carcinoma (HCC) has specific imaging criteria such as arterial hyperenhancement, contrast washout, and pseudocapsule that allow it to be diagnosed with confidence and relative accuracy.  However, a novel HCC variant, steatohepatitic hepatocellular carcinoma (SH-HCC), has been described which tends to not exhibit the classic HCC imaging features. In this study, we explored alternative secondary MR features of HCC such as T1 and T2 signal intensity, intralesional fat, and restricted diffusion which may be more applicable in diagnosing steatohepatitic hepatocellular carcinoma.

Yoon-Chul Kim, Eunju Kim, Gabrielle Beck, Hans Peeters, Young Kon Kim

We apply a 3D continuous golden-angle radial sparse parallel (GRASP) sequence to gadoxetic acid-enhanced imaging of the liver at 3 T.  Arterial phase imaging may need high spatial and temporal resolution as well as correct timing of capturing arterial enhancement to obtain hemodynamic information of the tumor. Continuous golden-angle radial sampling provides a flexible retrospective selection of temporal window. We develop a technique that identifies the arterial peak from high temporal resolution data and reconstructs arterial phases with different temporal windows. The characteristics of hepatic arterial images after retrospective temporal resolution selection are demonstrated.

Ely Felker, Steven Raman, Bradley Bolster, Holden Wu, Kyung Sung, Ning Jin, Brenda Brown, David Lu

Conventional GRE-based MR elastography requires a breath hold of approximately 18 seconds per slice, which is difficult for some patients.  We compared a rapid GRE-based sequence (9 second breath hold) to conventional GRE in terms of quantitative liver stiffness (LS) measurement and image quality score (IQS), based on wave propagation and confidence mask coverage, determined by two independent radiologists.  The two sequences were equivalent in terms of LS measurement, but the rapid GRE sequence had significantly higher IQS for both readers.  Rapid GRE-based MR elastography may be an improved alternative to GRE in patients with limited breath hold capacity.

Di Zhu, Xianlun Zou, Hao Tang, Xiao Chen, Xiaoyan Meng, Zhen Li, Daoyu Hu

To evaluate the ability of magnetic resonance angiographic inflow-sensitive inversion recovery (IFIR-MRA) to assess hemodynamics of portal vein system in patients with portal hypertension, we compared visualized portal vein branching grade scores at different blood suppression inversion time (BSP TI) settings and signal intensity contrast ratio of the vessles and the liver parenchyma with color Doppler ultrasonograghy (CDUS) measured hemodynamics. Statistically significantly correlation demonstrated that IFIR-MRA of portal vein system has the potential to suggest hemodynamic changes, especially for RPV.

Na Yeon Han, Min Ju Kim, Beom Jin Park, Deuk Jae Sung, Ki Choon Sim, Ki Choon Sim, Sung Bum Cho

We performed the study to develop and validate a method for measuring the depth of tumor invasion (DoI) on magnetic resonance imaging (MRI) and to investigate the diagnostic performance of the measured DoI for stratifying T classification in patients with distal bile duct cancer. Our result showed that this newly developed method reliably measured DoI on T2-weighted MR images, and can be used for the preoperative T classification of distal bile duct cancer patients.

Katsuyoshi Ito, Akira Yamamoto, Kazuya Yasokawa, Minoru Hayashida, Daigo Tanimoto, Akihiko Kanki, Tomohiro Sato, Hidemitsu Sotozono, Takeshi Fukunaga, Koji Yoshida, Kazunori Moriya, Tomoyuki Okuaki

This study assessed the correlation between pancreatic exocrine function estimated by cine dynamic MRCP with a spatially selective IR pulse and T1 mapping of the pancreatic parenchyma on 3T MR imaging. There was a statistically significant correlation between the secretion grade of the pancreatic juice in cine-dynamic MRCP and T1 relaxation time of the pancreatic parenchyma. Therefore, T1 mapping of the pancreatic parenchyma will be used as collaborative, noninvasive technique of cine-dynamic MRCP with a spatially selective IR pulse for the estimation of pancreatic exocrine function.