Kristen Zakian¹, William Hatfield², Omer Aras², Kun Cao³, Derya Yakar⁴, Debra Goldman², Chaya Moskowitz², Amita Shukla-Dave², Yousef Mazaheri Tehrani², Samson Fine², James Eastham², and Hedvig Hricak^2
1Memorial Sloan-Kettering Cancer Center, New York, NY, United States, ²MSKCC, NY, United States, ³Peking University Cancer Hospital, Beijing, China,⁴Radboud University of Nijmegen Medical Centre, Nijmegen, Netherlands

The value of prostate cancer metabolic data for predicting clinical outcome is of high clinical interest. In the current study, we sought to confirm the prognostic potential of 1H-MRSI in a large surgical population with long-term followup. We examined data from 262 subjects who underwent endorectal MRI/MRSI followed by radical prostatectomy from 2003-2007. The data indicate that the volume of metabolic abnormality detected by MRSI is correlated with treatment failure and is an independent predictor of failure in a multivariate analysis which includes an NCCN-based clinical risk score and the number of positive biopsy cores.

Devkumar Mustafi¹, Sophie-Charlotte Gleber², Urszula Dougherty³, Marta Zamora¹, Tatjana Antic⁴, Stefan Vogt², Gregory S Karczmar¹, and Aytekin Oto^1
1Radiology, The University of Chicago, Chicago, IL, United States, ²Advanced Proton Source, Argonne National Laboratory, Lemont, IL, United States,³Medicine, The University of Chicago, Chicago, IL, United States, ⁴Pathology, The University of Chicago, Chicago, IL, United States

DCE-MRI is a standard component of multi-parametric prostate MRI protocols. Analysis of DCE-MRI data from prostate is usually based on the model that gadolinium distributes into two well-mixed compartments and assumes that gadolinium does not enter into the glandular lumen. However, this assumption has not been directly tested. The purpose of our study was to measure concentrations of gadolinium in the prostatic epithelia and lumens of the normal mouse following intravenous injection, using X-ray fluorescence microscopy imaging. We have quantitatively determined gadolinium distributions in mouse prostatic epithelia and lumens and demonstrated that intravenously administered gadolinium enters into mouse prostatic lumens.

Shiyang Wang¹, Harsh Agarwal², Gregory S. Karczmar¹, and Aytek Oto^1
1Radiology, University of Chicago, Chicago, IL, United States, ²Clinical Research Development, Philips Research North America, Briarcliff, Manor, NY, United States

Accurate modeling of T2 decay in prostate may improve the prostate cancer detection. Glandular structure of prostate suggests multi-compartment T2 decay of prostate. In this manuscript multi-echo TSE MRI over TE=24 to 396msec was acquired and fitted to mono and bi-exponential T2 decay models. Individual parameters from mono and bi exponential fitting were able to show significant difference between cancer and normal prostate tissue. An accelerated ME-TSE is repeated twice and compared with un-accelerated ME-TSE MRI showed that accelerated ME-TSE is accurate but is less precise may be due to lower SNR.

Brijesh Kumar Yadav^1,2, Jaladhar Neelavalli^1,2, Uday Krishnamurthy^1,2, Yimin Shen², Gabor Szalai³, Bing Wang³, Tinnakorn Chaiworapongsa^3,4, Edgar Hernandez Andrade^3,4, Nandor Gabor Than^3,4, Ewart Mark Haacke^1,2, and Roberto Romero^3
1Department of Biomedical Engineering, Wayne State University, Detroit, Michigan, United States, ²Department of Radiology, Wayne State University, Detroit, Michigan, United States, ³Perinatology Research Branch, NICHD, NIH, DHHS, Wayne State University, Detroit, Michigan, United States,⁴Department of Obstetrics and Gynecology, Wayne State University, Detroit, Michigan, United States

Placental insufficiency is one of the leading causes of abnormal materno-fetal circulation which could lead to intrauterine growth restriction. The placenta is a dynamic structure which changes with the gestational age. Hence understanding the natural course of placental perfusion characteristics in normal mice pregnancy is critical to contrast it with changes that occur in the different pathologies at different gestational ages. This study reports the quantification of longitudinal variations in perfusion characteristics of the high and low blood perfusion compartments of normal murine placenta using DCE MRI.

Wei-Ching Lo¹, Yong Chen², Jesse I. Hamilton¹, Dan Ma¹, Yun Jiang¹, Katherine L. Wright¹, Mark A. Griswold^1,2, Vikas Gulani^1,2, and Nicole Seiberlich^1
1Dept. of Biomedical Engineering, Case Western Reserve University, Cleveland, OH, United States, ²Dept. of Radiology, University Hospitals of Cleveland and Case Western Reserve University, Cleveland, OH, United States

Motion artifact suppression is a major challenge in abdominal magnetic resonance imaging, and particularly in quantitative imaging. Here, a new technique is introduced, where 3D high-resolution abdominal T₁ maps are obtained during free-breathing by combining inversion-recovery Look-Locker method, respiratory self-navigation, and 3D golden angle through-time spiral GRAPPA reconstruction. T₁ values from different tissues are in excellent agreement with breath-hold data and literature. This technique may be beneficial for those who cannot hold their breath during MR acquisition or need a larger spatial coverage or higher spatial resolution.

Xiaoming Bi¹, Yutaka Natsuaki¹, Kevin Johnson², and Gerhard Laub^3
1Siemens Healthcare, Los Angeles, CA, United States, ²Siemens Healthcare, Tucson, AZ, United States, ³Siemens Healthcare, San Francisco, CA, United States

TrueFISP sequence allows fast liver imaging at 1.5T with good image quality. Its application at 3T remains challenging due to increased banding artifacts originating from phase dispersion. In this work a robust free-breathing liver imaging method was developed using TrueFISP sequence by incorporating multiple phase-cycled acquisitions and non-rigid motion correction before averaging. Protocol was optimized from numerical simulation and validated from in-vivo studies. Using the proposed method, high spatial resolution, high blood-liver contrast, artifact-free liver images were acquired at 3T under free breathing.

Valentina Taviani¹, Daniel Litwiller², Andreas M. Loening¹, Manojkumar Saranathan¹, Brian A. Hargreaves¹, and Shreyas S. Vasanawala^1
1Radiology, Stanford University, Stanford, CA, United States, ²GE Healthcare, Rochester, MN, United States

Reduced-FOV Single-Shot Fast Spin Echo (SSFSE) can provide high-resolution images of targeted regions free from motion artifacts and with improved sharpness due to the reduced echo train length. Outer volume suppression using quadratic phase pulses can be used to effectively restrict the phase-encoded FOV. The associated SAR penalty can be offset using variable refocusing flip angles. Although the large saturation bands needed for body applications cause misregistration artifacts between fat and water even for relatively high RF bandwidths, several novel approaches presented here can mitigate this effect. The performance of the proposed technique is illustrated in phantoms and specific clinical cases.

Jouke Smink¹, Marco Nijenhuis¹, and Jan P Groen^1
1Philips Healthcare, Best, Netherlands

Silent ZTE imaging with a large FOV and the standard available prepulses to modify the contrast was investigated on standard 1.5T clinical scanners. With an echo time of 60 µs and standard B1 limitations, the readout gradient had to be kept low enough to both limit the number of missed samples as well as to excite a FOV of at least 500 mm. We obtained motion compensated; fat-suppressed, T1- and T2-weighted scans in the abdomen. ZTE imaging with a large FOV seems feasible. The limitations of the standard clinical scanner were overcome by using a straight forward sequence adaptation.

Aliya Gifford^1,2, Theodore F Towse^1,3, and Brian Welch^1,4
1Institute of Imaging Science, Vanderbilt University, Nashville, Tennessee, United States, ²Chemical and Physical Biology Program, Vanderbilt University, Nashville, TN, United States, ³Department of Physical Medicine and Rehabilitation, Vanderbilt University School of Medicine, Nashville, TN, United States,⁴Radiology and Radiological Sciences, Vanderbilt University, Nashville, TN, United States

This report shows the results of three methods of computing fat-water separation and how the resulting fat-water MRI derived fat-signal-fraction (FSF) values correlate to CT Hounsfield Units in human white adipose tissue. These results show that the FSF values as calculated using 6 echoes, 9 fat peaks, and R₂* correction, are tightly correlated (R²=0.887) to the density of tissue as measured by differences in CT Hounsfield Units values for subjects with BMI < 24 after exposure to cold. The strength of correlation drops dramatically for worse fat-water separation models.

Brice Masi^1,2, Teodora-Adriana Perles-Barbacaru^3,4, Caroline Laprie⁵, Helia Dessein^1,2, Monique Bernard^3,4, Alain Dessein^1,2, and Angèle Viola^3,4
1INSERM U906, Marseille, France, ²GIMP UMR_S 906, Aix-Marseille Université, Marseille, France, ³CRMBM UMR CNRS 7339, Marseille, France, ⁴Aix-Marseille Université, Marseille, France, ⁵Laboratoire VET-HISTO, Marseille, France

Schistosomiasis, a tropical parasitic infection, often leads to fatal liver fibrosis. The hepatosplenic disease in a mouse model of schistosomiasis is studied in vivo by high resolution volumetric MRI and quantitative T₂-mapping. As early as 6 weeks after infestation, MRI reveals hepato- and splenomegaly, as well as portal hypertension. At 10 weeks, multifocal lesions with increased T₂ appear on MRI. The area fraction of increased T₂ in the livers correlates with the area fraction of fibrotic tissue revealed with sirius red staining. This multimodal MRI approach assesses hepatosplenic disease and liver fibrosis non-invasively and is useful for treatment monitoring.