Colin Kim¹, Cody Johnson¹, James Rice², and Alejandro Roldán-Alzate^1
1Medical Physics and Radiology, University of Wisconsin-Madison, Madison, WI, United States, ²Mechanical Engineering, University of Wisconsin-Madison, Madison, WI, United States

Lower urinary tract symptoms (LUTS) and changes in bladder function occur frequently as individuals age, requiring a non-invasive method of imaging the bladder. This study utilized 3D MRI acquisition on both an in vitro bladder model and an in vivo human subject to analyze deformation patterns during the bladder voiding process and validated results with high-speed optical imaging. Both quantitative and qualitative analyses were conducted. This study serves to discover novel methods of in vivo MRI bladder imaging during the voiding process.

Bohong Cao¹, Qing Li¹, Peirong Xu², Pu-Yeh Wu³, Shuai Jiang², and Jianjun Zhou^1
1Radiology, Zhongshan Hospital Fudan University, Shanghai, China, ²Urology, Zhongshan Hospital Fudan University, Shanghai, China, ³MR Research, GE Healthcare, MR Research, Beijing, China

In this study, we expanded the target population by including patients after treatment and with recurrent bladder cancer to further evaluate the diagnostic performance of VI-RADS. The diagnostic performances of VI-RADS were good in all subgroups including the primary, post-treatment and recurrence groups (AUC > 0.90). No significant differences were observed in diagnostic efficacy of VI-RADS between the primary group and the post-treatment group, and between the primary group and the recurrence group. Overall, this study demonstrated that VI-RADS can be considered an effective preoperative imaging staging tool for a wider range of bladder cancer patients.

Shichao Li¹, Ping Liang¹, Yanchun Wang¹, Yaqi Shen¹, Xuemei Hu¹, Daoyu Hu¹, Xiaoyan Meng¹, and Zhen Li^1
1Department of Radiology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China

This study explored the clinical value of volumetric apparent diffusion coefficient (ADC) histogram analysis and Vesical Imaging Reporting and Data System (VI-RADS) in differentiating muscle-invasive bladder cancer (MIBC) from non-muscle-invasive bladder cancer (NMIBC), and demonstrated that both are helpful and the volumetric ADC histogram can provide additional value to VI-RADS.

Qian Cai¹, Huan jun Wang¹, Yi ping Huang¹, Long Qian², Yan Guo¹, Zhi hua Wen¹, Long yuan Ouyang¹, and Mei qin Li^1
1Department of Radiology, The First Affiliated Hospital of Sun Yat-sen University, Guangzhou, China, ²MR Research, GE Healthcare, Beijing, China

The prospective study aims to investigate the value of Synthetic MRI in evaluating the grading of bladder cancer (BCa). A total of 31 patients with pathologically confirmed BCa were enrolled. Regions of interest were manually drawn by two radiologists. Our results indicated that there were significant differences in the mean T2 and PD values between high- and low-grade BCa. The area under the ROC curve of the mean T2 and PD values were 0.761 and 0.880, respectively. Synthetic MRI is helpful for discriminating low- and high-grade BCa.

Bo Dai¹, Meiyun Wang ¹, Fengshan Yan¹, Zhiwei Shen², Yan Bai¹, and Nan Meng^1
1Henan Provincial People's Hospital, Zhengzhou, China, ²Philips healthcare, Beijing, China

In the preliminary experiment, we found that there were hyperintense amide proton transfer weighted (APTw) signal in urine, which may interfere with the contrast of APTw signal in bladder lesion. In this study, we aim to explore the feasibility and features of urine APTw imaging in vitro and in vivo, and inhibite the urine APTw signal for better display of bladder lesions using optimal parameters.

Wenhao Fu¹, Yang Peng¹, Guanglei Tang¹, Weibo Chen², Kan Deng³, Zhongping Zhang³, Yingjie Mei³, and Jian Guan^1
1Department of Radiology， the First Affiliated Hospital of Sun Yat-Sen University, Guangzhou, China, ²Philips Healthcare, Shanghai, China, ³Philips Healthcare, Guangzhou, China

Functional MRI, such as DWI and MTI, have been used to evaluate male infertility. Amide proton transfer (APT) is a novel MRI technique in the level of molecular imaging, which employs the chemical exchange of endogenous amide proton. This study investigated the relationship between amide proton transfer (APT) signal intensity (SI) changes with age in adults. According to the initial results of this research, we found that APT SI of testes was positively correlated age, which suggested that APT could be a potential biomarker for spermatogenic function.

Xue Ren¹, Ailian Liu¹, Lihua Chen¹, Shuang Li¹, Yue Wang¹, Jiazheng Wang², Qingwei Song¹, Sun Peng², Renwang Pu³, and Yuanfei Li^1
1The First Affiliated Hospital of Dalian Medical University, Dalian, China, ²Philips Healthcare, Beijing, China, ³First Affiliated Hospital of Dalian Medical University, Dalian, China

Accurate identifying prostate cancer (PC) from benign prostatic hyperplasia (BPH) is of great significance for timely and proper treatment. Amide proton transfer (APT) is a novel MRI method sensitive to several kinds of cancers. mDIXON-Quant is a powerful quantitive technique for simultaneous fat quantification and R2* mapping, which can reflect the tissue contents and properties. This study aims to assess the diagnostic performance of APT and mDIXON-Quant on differentiating prostate cancers and benign prostate hyperplasia. Results indicate that the combination of APT and mDIXON-Quant can enhance the differential diagnosis of PC and BPH.

Aritrick Chatterjee^1,2, Xiaobing Fan¹, Aytekin Oto ^1,2, and Gregory Karczmar^1,2
1Department of Radiology, University of Chicago, Chicago, IL, United States, ²Sanford J. Grossman Center of Excellence in Prostate Imaging and Image Guided Therapy, Chicago, IL, United States

This study introduces a new quantitative mapping technique referred to as Four Quadrant mapping of Hybrid Multi-dimensional MRI data and evaluates its use for diagnosis of prostate cancer. Each image voxel can be represented as a vector in a 2D plot with components ‘∆T2/∆b’ and ‘∆ADC/∆TE’. Cancers contain a significantly higher percentage of voxels in quadrant 4 (PQ4), and a lower percentage of voxels in quadrant 2 (PQ2), smaller amplitude and angle compared to benign tissue. The quadrant analysis metrics resulted in AUC of 0.893 for differentiation of cancer from benign tissue, and showed moderate correlation with Gleason score (|ρ|=0.38-0.61). 

Stephanie Alley¹, Uulke Van der Heide², Cynthia Ménard³, and Samuel Kadoury^1,3
1Biomedical Engineering, Polytechnique Montréal, Montréal, QC, Canada, ²Radiation Oncology, The Netherlands Cancer Institute, Amsterdam, Netherlands, ³Centre Hospitalier de l’Université de Montréal, Montréal, QC, Canada

Multi-parametric magnetic resonance imaging has come to play an important role in the diagnosis and treatment of prostate cancer. Despite numerous advances in the acquisition, processing, and analysis of these images, a great deal of variability still exists in the reliability of imaging-based information. In an effort to initialize a framework for standardizing the processing of prostate imaging data, we present a systematic evaluation of the effect that bias field correction and intensity normalization of T2w images have on downstream analyses. We show that this assessment allows us to achieve improved accuracy for tumor localization within the prostate.

Nila Mu¹, Ailian Liu¹, Lihua Chen¹, Pengyun Zhang¹, Yunsong Liu¹, Changjun Ma¹, Jiazheng Wang², Liangjie Lin², Qingwei Song¹, and Renwang Pu^1
1The First Affiliated Hospital of Dalian Medical University, Dalian, China, Dalian, China, ²Philips Healthcare, Beijing, China, Beijing, China

 It is difficult to identify prostate tumors and prostate hyperplasia in clinical practice with conventional MR imaging methods. T2mapping is a non-invasive technique, which can analyze the T2 value of the organization quantitatively. In this study, we aimed to evaluate the correlation between T2 mapping and Intravoxel incoherent motion. The results show that T2 values were significantly associated with all parameters of IVIM except fast ADC mono, and have no concern with prostate cancer or benign prostatic hyperplasia. 

Ethan Leng¹, Joseph Koopmeiners², Lin Zhang², and Gregory John Metzger^1
1Center for Magnetic Resonance Research, Minneapolis, MN, United States, ²School of Public Health, Division of Biostatistics, University of Minnesota, Minneapolis, MN, United States

It is important to not only identify prostate cancer (PCa) when it is present, but also to determine the aggressiveness of PCa. In this work, we developed a novel two-stage classification model for simultaneous detection of PCa on prostate MRI and localization of aggressive, high-grade PCa, using both quantitative MRI and radiomic features. The first-stage classifier was trained to detect cancer on a voxel-wise basis, and achieved an AUC of 0.818. The second-stage classifier was trained to predict the aggressiveness of candidate regions automatically derived from the voxel-wise predictions of the first stage, and achieved an AUC of 0.779.

Lihua Chen¹, Ailian Liu¹, Pengyun Zhang¹, Nila Mu¹, Yunsong Liu¹, Changjun Ma¹, Jiazheng Wang², Qingwei Song¹, and Renwang Pu^1
1The First Affiliated Hospital of Dalian Medical University, Dalian, China, ²Philips Healthcare, Beijing, China

It is difficult to differentiate prostate tumors and prostate hyperplasia using conventional MR imaging methods. Amide proton transfer-weighted  imaging is a novel MRI imaging tool for detection of amide protons in mobile cellular proteins and peptides. We aimed to evaluate the differential diagnosis of prostate cancers and benign prostatic hyperplasia using APT and IVIM. Results showed that prostate cancers were associated with higher APT values than benign prostate hyperplasia, while diffusion and perfusion parameters of IVIM were lower in prostate cancers. The diagnostic efficiency between prostate cancer and prostatic hyperplasia was higher with combinational use of APT and IVIM parameters.

Lihua Chen¹, Ailian Liu¹, Yan Guo², and Xin Li^2
1The First Affiliated Hospital of DaLian Medical University, Dalian, China, ²GE Healthcare, China, Beijing, China

DWI might be used as a biomarker for tumor aggressiveness, and various reports have been made on using DWI in distinguishing PCa from BPH. The primary parameter of DWI, ADC must be obtained with a high b value DWI, to limit the perfusion effect. The term radiomics has attracted increased attention in recent years, which was presented by Lambin in 2012. The aim of this study was to establish and evaluate the efficiency of radiomics model in distinguishing PCa from BPH based on DWI sequence and clinical information, and to compare the efficiency of ROI sketched by two different methods.

Shintaro Horii¹, Yoshiko Ueno², Yuichiro Somia¹, Ryuji Shimada¹, Keitaro Sofue², Yasuyo Urase², Wakiko Tani¹, Yu Ueda³, Akiko Kusaka¹, and Takamichi Murakami^2
1Center for Radiology and Radiation Oncology, Kobe University Hospital, kobe, Japan, ²Department of Radiology, Kobe University Graduate School of Medicine, Kobe University Hospital, kobe, Japan, ³Philips Japan MR Clinical Science, tokyo, Japan

This study aimed to compare the image quality and the quantitative DCE-MRI parameters using the k-space weighted image contrast reconstruction with variable-density golden angle stack-of-stars acquisition (4D-FB) to those of the conventional 3D-T1W turbo field echo sequence (e-THRIVE) in prostate cancer (PCa). Image quality assessment and the receiver operating characteristic curve (AUC) analysis of quantitative DCE-MRI parameters in discrimination PCa from normal tissue were performed. 4D-FB showed significantly higher SNR compared to e-THRIVE. No significant differences were observed in AUCs for each quantitative DCE-MRI parameter. 4D-FB may improve image quality of DCE-MRI with keeping effective pharmacokinetic information in PCa assessment.

Xiaobing Fan¹, Aritrick Chatterjee¹, Jay M Pittman¹, Ambereen Yousuf¹, Tatjana Antic², Gregory S Karczmar¹, and Aytekin Oto^1
1Radiology, The University of Chicago, Chicago, IL, United States, ²Pathology, The University of Chicago, Chicago, IL, United States

We evaluated dynamic contrast enhanced MRI with a split injection protocol for diagnosis of prostate-cancer. We injected 30% of the standard dose, followed after two mins by 70% of the standard dose of gadoterat-meglumine. A signal intensity form of the standard Tofts model was used to extract physiological parameters. On average cancer had larger K^trans and smaller v_e than normal tissue obtained from both doses. Receiver operating characteristic analysis showed that area under curve was 0.776 for a combination of all parameters from the 30% and 70% doses. The split injection protocol combined with quantitative analysis may increase diagnostic accuracy.

Anne Adlung¹, Fabian Tollens², Nadia Karina Paschke¹, Jennifer Hümsch¹, Niklas Westhoff³, Daniel Hausmann^2,4, Lothar Rudi Schad¹, Dominik Nörenberg², and Frank Gerrit Zöllner^1,5
1Computer Assisted Clinical Medicine, Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany, ²Department of Radiology and Nuclear Medicine, Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany, ³Department of Urology and Urosurgery, Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany, ⁴Department of Radiology, Kantonspital Baden, Baden, Switzerland, ⁵Mannheim Institute for Intelligent System in Medicine, Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany

Prostate cancer is the most common tumor in men. ²³Na-MRI provides complementary information to multiparametric-MRI. Tissue sodium concentration (TSC) quantification depends on sodium references-usually external phantoms.

This study investigates TSC-quantification based on internal references (iliac-artery).

²³Na-MRI of 19 male patients with suspected PCa was included. TSC in the prostate was quantified based on external reference vials and based on the iliac artery.

Three patients showed a PI-RADs-5 lesion and had an elevated TSC which is in alignment with prvious studies. No significant differences between both methods were found in the whole prostate.

Internal references for TSC quantification could simplify ²³Na-MRI.

Huijia Yin¹, Dongdong Wang¹, Ruifang Yan¹, Xuekun Li¹, Kaiyu Wang², and Dongming Han^1
1MR, the First Affiliated Hospital of Xinxiang Medical University, Xinxiang, China, ²MR Research China,GE Healthcare, Xinxiang, China

This study explored the diagnostic value of APT and DKI in prostate cancer(PCa) and benign prostatic hyperplasia(BPH), and compared the diagnostic advantages of the two techniques and their relationship with the risk of prostate cancer. Our study have shown that APT and DKI both can differentiate PCa and BPH, but DKI has higher diagnostic value, and have strong correlation with Gleason score.They all have the potential to be used in routine clinical practice as new indicators to evaluate the risk of PCa, and to help early diagnosis and personalized diagnosis and treatment of PCa.

Yachao Liu¹, Hongkai Yu², Jiajin Liu¹, Xiaojun Zhang¹, Mu Lin³, Holger Schmidt⁴, Jiangping Gao², and Baixuan Xu^1
1Department of Nuclear Medicine, Chinese PLA General Hospital, Beijing, China, ²Department of Urology Surgery, Chinese PLA General Hospital, Beijing, China, ³MR collaborations, Diagnostic Imaging, Siemens Healthcare, Shanghai, China, ⁴MR Education, Customer Services, Siemens Healthcare, Erlangen, Germany

The purpose of this study is to evaluate the feasibility and diagnostic performance of ¹⁸F-PSMA PET/CT-ultrasound (PET/CT-US) or PET/MRI-ultrasound (PET/MRI-US) fusion targeted biopsy for intra-prostatic PET-positive lesions. 55 candidates were prospectively enrolled for PET/CT-US or PET/MRI-US fusion targeted biopsies at solitary PET-positive lesions. A total of 178 core biopsies were performed on 55 patients. 146 biopsy cores (82.0%, 146/178) from 51 (92.7%, 51/55) patients were positive for prostate cancer; 47 (85.5%, 47/55) were clinically significant prostate cancer. 18F-PSMA PET/CT-US or PET/MRI-US fusion-targeted prostate biopsy are feasible for prostate cancer diagnosis and has high detection rate of clinically significant prostate cancer.

Melline Gabrielle Maria Schilham¹, Patrik Zamecnik¹, Bas Israel¹, Bastiaan Privé¹, Mark Rijpkema¹, Jelle Barentsz¹, James Nagarajah¹, Martin Gotthardt¹, and Tom Scheenen^1
1Medical Imaging, Radboudumc, Nijmegen, Netherlands

In this head-to-head comparison study, 45 prostate cancer patients underwent both USPIO-enhanced MRI (nano-MRI) and prostate-specific membrane antigen PET/CT for the purpose of lymph node staging. The results of both scans were compared on number, size and location of suspicious lymph nodes. Both modalities identified suspicious LNs which were missed by the other. Both modalities identified suspicious LNs in all anatomical regions of the pelvis, however nano-MRI appeared to be superior in detecting smaller suspicious LNs.