Traditional Posters: Body Imaging

Christian Geppert¹, Rolf Janka², Berthold Kiefer¹, Michael Uder², Evelyn Wenkel<sup>2

1</sup>MR Oncology, Siemens Heatlthcare, Erlangen, Germany; ²Radiologisches Institut, Universitätsklinikum Erlangen, Erlangen, Germany

In non-fatsuppressed dynamic breast imaging, it is a well accepted recommendation to acquire data at or close to echo times that fulfil the in-phase condition for fat and water, such as 4.7ms at 1.5T, in order to avoid partial volume effects that lead to signal cancellation at fat/water interfaces. Thus it is usually suggested of using either in-phase TE or “TE less than 1.2ms” resulting in a phase difference of below 90°. In a comparable parameter setting this would result in a decrease of 50% of the total acquisition time. With current gradient systems and fast imaging sequences this has now become possible without compromising the matrix size or the bandwidth. In this work we have set up an interleaved protocol approach to achieve a direct comparison of a minimum TE acquisition with a clinical standard protocol.

2476. Improved Diagnostic Accuracy in DCE MR-Mammography by Normalization of Kinetic Parameters Following AIF Deconvolution

Endre Grøvik¹, Kjell-Inge Gjesdal², Kathinka Kurz Dæhli³, Atle Bjørnerud<sup>4

1</sup>University of Oslo, Oslo, Norway; ²Sunnmøre MR-klinikk, Aalesund, Norway; ³Stavanger University Hospital, Stavanger, Norway; ⁴Rikshospitalet University Hospital, Oslo, Norway

This work presents a method for improving diagnostic accuracy in DCE MR-mammography by normalization of kinetic parameters following AIF deconvolution. The permeability related kinetic parameter Ktrans and the Ktrans-ratio between cancer tissue and breast parenchyma were investigated and compared based on their ability to differentiate between malignant and benign lesions. The result showed that employing a normalization approach may improve the diagnostically performance of the pharmacokinetic model by diminishing the prospective errors in the extracted AIF.

2477. Influence of Contrast Arrival Time and Temporal Resolution in Diagnosis of Breast Cancer with DCE-MRI

Hendrik Laue¹, Anja Hennemuth¹, Volker Diehl^1,2, Markus Thorsten Harz¹, Horst Karl Hahn¹, Heinz-Otto Peitgen<sup>1

1</sup>Fraunhofer MEVIS, Bremen, Germany; ²Institute of Magnetic Resonance Imaging, Central Hospital St.-Juergen-Strasse, Bremen, Germany

The consensus on diagnosis of breast cancer with DCE-MRI is the use of sequences with high spatial and low temporal resolution, because of the in inhomogeneous distribution of pharmacokinetic properties in the tumor and the requirement to detect small lesions. The diagnostic in breast MRI today is therefore based on simple curve shapes rather than pharmacokinetic modeling. In this work, some pharmacokinetic modeling of contrast arrival time (CAT) and variation of low temporal resolution are carried out to identify pitfalls in the application and to identify techniques beneficial for the diagnostic performance of breast MRI.

2478. Preliminary Results Using a Split Dynamic Time Series for DCE MR-Mammography

Kjell-Inge Gjesdal¹, Endre Grøvik², Atle Bjørnerud³, Kathinka Kurz Dæhli<sup>4

1</sup>Sunnmøre MR-klinikk, Aalesund, Norway; ²University of Oslo, Oslo, Norway; ³Rikshospitalet University Hospital, Oslo, Norway; ⁴Stavanger University Hospital, Stavanger, Norway

This work presents the preliminary results of an ongoing MR-mammography study. In this study two dynamic sequences are run in an interleaved fashion during contrast enhancement. By using this approach both high temporal and high spatial resolution images can be produced and analyzed for the evaluation of breast cancer using one single dose of a Gd-based contrast agent. A comprehensive list of biomarkers is presented along with their statistical values.

2479. Can Diffusion Weighted Imaging/Apparent Diffusion Coefficient Mapping and Dynamic Contrast Magnetic Resonance Imaging Provide Histological Phenotyping of Breast Cancer in Basal and Luminal Subtypes?

Michael A. Jacobs¹, Riham H. El Khouli², Katarzyna J. Macura¹, Sarah Mezban¹, Ihab Kamel¹, David A. Bluemke<sup>2

1</sup>The Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, MD, United States; ²Department of Radiology and Imaging Sciences, National Institutes of Health, Bethesda, MD, United States

By using a combined DWI/ADC and DCE approach to investigate histological characteristics of breast cancer a better understanding of breast cancer aggressiveness can be realized. Functional imaging such as DWI and DCE-MR is feasible and thus, combined DWI/ADC mapping, and DCE-MR provides radiological biomarkers of molecular environment and could provide targets for image-guided biopsy of highly aggressive tumor regions.

2480. Principal Component Analysis of Breast DCE-MRI: Evaluation of Clinical Protocols at Two Temporal Resolutions

Daria Badikhi¹, Myra Shapiro-Feinberg², Erez Eyal³, Edna Furman-Haran⁴, Dov Grobgeld¹, Hadassa Degani<sup>1

1</sup>Biological Regulation, Weizmann Institute of Science, Rehovot, Israel; ²Radiology, Meir Medical Center, Kfar Sabah, Israel; ³Biological Regulation, Weizmann Institute of Science, Israel; ⁴Biological Services, Weizmann Institute of Science, Rehovot

Principal component analysis (PCA) of clinical breast DCE MRI datasets, recorded at two different temporal resolutions (80 s and 120 s), was tested and evaluated for its diagnostic ability. We found that PCA can differentiate with high accuracy between benign and malignant lesions at both temporal resolutions, however, discriminative ability between invasive ductal and lobular carcinoma can be reached only at the higher temporal resolution. Overall, PCA was found to be a useful, standardized, fast, and objective tool for computer aided diagnosis of breast lesions

2481. Diffusion Weighted and Dynamic Contrast Enhanced MRI in Evaluation of Treatment Effects During Neoadjuvant Chemotherapy in Breast Cancer Patients

Line R. Jensen¹, Benjamin Garzon¹, Mariann G. Heldahl¹, Tone F. Bathen¹, Pål E. Goa¹, Steinar Lundgren^1,2, Ingrid S. Gribbestad<sup>1

1</sup>Department of Circulation and Medical Imaging, Norwegian University of Science and Technology, Trondheim, Norway; ²Department of Oncology, St. Olavs University Hospital, Trondheim, Norway

The purpose of this study was to use MRI for early evaluation of treatment effects in breast cancer patients undergoing neoadjuvant chemotherapy, and to identify MRI parameters at 3T that correlate to treatment response. In addition, the reproducibility of diffusion weighted MRI was assessed. The ADC values from two baseline examinations showed good reproducibility, with ICC of 0.84. The best predictors of pathologic treatment response were the change in the longest diameter measured on MRI, followed by mean and skewness of ADC, and Ktrans entropy.

2482. Assessing 3D Resolution of DCE-MRI for Optimization and Standardization of Breast Screening Protocols

Marco Borri¹, Maria Schmidt¹, Erica Scurr¹, Toni Wallace¹, Steven Allen¹, Nandita deSouza¹, Martin O. Leach<sup>1

1</sup>CR-UK and EPSRC Cancer Imaging Centre, Institute of Cancer Research and Royal Marsden Hospital, Sutton, Surrey, United Kingdom

Spatial resolution of 3D fat-suppressed DCE pulse sequences depends on many parameters, and parity of protocols across breast screening centres is highly desirable. The objective of this work was to propose methods for quality assurance in breast screening programmes. We compared the image quality achieved with two different k-space sampling patterns, Radial and Linear, on a breast screening sequence. Resolution was evaluated with Test Objects and on Clinical Data, and, considering all three directions, was superior for Linear. The Image Analysis methodologies used were found to be robust and reproducible, and are therefore candidates to become quality assurance tools.

2483. Influence of Spatial Heterogeneity on the Diagnostic Accuracy of DCE-MRI in Breast Tumor Characterization