Kexin Hao, Gwenael Layec, Corey Hart, Christopher Conlin, Kristi Carlston, Vivian Lee, Jeff Zhang

This study examined the relationship between R₂* measurements from BOLD MRI and deoxyhemoglobin (HHb) measurements from near-infrared spectroscopy (NIRS) in calf muscle of subjects with varying degrees of peripheral artery disease (PAD). Following plantar-flexion exercise, the time required for R₂* and HHb to recover to resting-state values was recorded. Linear regression was used to relate recovery time between R₂* and HHb. This quantitative relationship enables estimation of HHb from MRI-measured R₂*, which can help to improve the assessment of PAD since MRI can easily be performed for muscle tissue that is too deep for NIRS evaluation.

Robert Kraft, Craig Hamilton, Peter Brubaker, W. Scott Hoge, M. Constance Linville, J. Thomas Becton, Richard Thompson, Mark Haykowsky, Dalane Kitzman

The pathophysiology of Heart Failure Patients with Preserved Ejection Fraction is poorly understood but there is increasing evidence that skeletal muscle blood flow and metabolism play important roles in this disease. Accurately and non-invasively measuring skeletal muscle blood flow with sufficient temporal resolution to measure skeletal muscle blood flow dynamics in individual muscles is challenging.  We present a optimized version of pseudo-Continuous ASL capable of measuring blood flow map of the calf every 16 seconds.  Data from two healthy adults is presented.

Celine Baligand, Jedrzej Burakiewicz, Melissa Hooijmans, Olivier Scheidegger, Matt Hall, Paola Porcari, Erik Niks, Pierre Carlier, Christopher Clark, Andrew Blamire, Jan Verschuuren, Hermien Kan

Cellular sizes in skeletal muscle are significantly larger than in the brain. Therefore standard spin-echo (SE)-DTI with inherently short diffusion times may lack sensitivity for the study skeletal muscle of neuromuscular disorders (NMDs). Alternatively, stimulated-echo (STE-)DTI allows for much longer diffusion times, increasing sensitivity to cell size. Due to the challenges presented by fat replacement STE-DTI has not been previously applied in NMDs. Here, we show that STE-DTI is feasible in Becker Muscular Dystrophy patients, and can detect FA differences compared to healthy controls in mildly affected muscles.

Xingui Peng, Shenghong Ju

This study aimed to measure the BOLD response in the calf muscle in T2DM patients during post-occlusive reactive hyperemia and to study whether T1ρ MR Imaging of calf muscle could differentiate T2DM patients from normal subjects.  Twenty-two T2DM patients and twenty age-matched healthy volunteers were performed MR scanning. T1ρ relaxation time and maximal ΔT2* change (ΔT2*max) and time to peak (TTP) were measured. Our results showed that the lower degree of the increase (ΔT2*max and TTP) in calf muscles of DM patients. In addition, T1ρ relaxation time in TA muscle was significant higher in DM patient than in healthy subjects. 

Friedemann Freitag, Thomas Baum, Michael Dieckmeyer, Jan Kirschke, Holger Eggers, Christian Buerger, Cristian Lorenz, Dimitrios Karampinos

Chemical shift encoding-based water-fat MRI derived proton density fat fraction (PDFF) of the paraspinal muscles has been emerging as important surrogate marker in subjects with intervertebral disc disease, osteoporosis, sarcopenia, and neuromuscular disorders. However, measurements of paraspinal muscle PDFF are currently limited in clinical routine due to the required time-consuming manual segmentation procedure. The present study aimed to develop an automatic segmentation algorithm of the paraspinal muscles at the lumbar spine based on water-fat MRI and compared the performance of this algorithm to ground truth data based on manual segmentation.

Radka Klepochová, Ladislav Valkovic, Martin Gajdošík, Thomas Hochwartner, Norbert Bachl , Harald Tschan, Michael Krebs, Siegfried Trattnig, Martin Krššák

Carnitine plays an important role in fat metabolism. A long-echo time proton magnetic resonance spectroscopy protocol was implemented for detection of skeletal muscle acetylcarnitine during the day and after exercise on a clinical 7T scanner in the thigh (vastus lateralis) muscle. Our observation point towards diurnal changes of acetylcarnitine concentration which tended to be higher in the morning than after lunch. Moreover, following 10 minutes of high-intensity exercise the concentration significantly increased and again significantly decreased 15 minutes after cessation of the exercise. Our data emphasize the need for strict standardization,physical activity and dietary conditions for the measurement of the acetylcarnitine/carnitine.

Chiara Giraudo, Stanislav Motyka, Michael Weber, Manuela Karner, Christoph Resinger, Siegfried Trattnig, Wolfgang Bogner

STEAM-based DTI was applied to investigate lower limbs’ muscle tears in athletes using the contralateral muscles as reference.To account for possible physiological differences in DTI metrics between right and left limb, a ratio between two ROIs on the injured side (i.e.,one on the tear and one on a healthy area) and two ROIs on the contralateral limb (i.e.,both on healthy areas) was used. The ratio showed that structural changes, expressed by modifications in MD, FA, RD, fibers’ number and length, occur in muscle tears and are quantifiable by DTI.These findings are expected to improve the therapeutic management of muscle injuries.

Li Yiwen, Yuan Huishu, Xie Lizhi

The purpose of the current study is to assess the potential difference of multifidus muscle between non-specific chronic low back pain patients and the healthy individuals using DTI and to compare the sensitivity of DTI to conventional lumbar MRI in detecting muscle pathological changes. DTI and conventional MRI parameters were obtained including FA, ADC, MD and tCSA, fCSA, fCSA/tCSA ratio. Compared to the healthy individuals, NCLBP patients demonstrated differences in DTI parameters of bilateral multifidus muscles. We conclude that DTI is more sensitive in detecting paraspinal muscle pathological changes in the early stage of lumbar degeneration than conventional lumbar MRI.

Junichi Hata, Kanehiro Fujiyoshi, Osahiko Tsuji, Yuji Komaki, Keigo Hikishima, Masaya Nakamura, Hideyuki Okano

We developed a technology that the muscle composition ratio can be non-invasively visualize at q-space imaging. And, these MR image confirmed validation by comparison to the skeletal muscle histology. We scanned diffusion data using 7T MRI scanner and performed analysis to calculate QSI index. The mice lower leg was stained by several solutions to enable muscle typing. As a result, the cell size by sections showing the correlation between the QSI indices. Moreover, the visualization in a staining compared, it is possible to obtain the same image. We confirmed validation by comparing the stained image to QSI.

Martin Schwartz, Petros Martirosian, Guenter Steidle, Michael Erb, Bin Yang, Fritz Schick

Simultaneous multi-slice diffusion-weighted imaging (DWI) was applied on human right calf for imaging Spontaneous Mechanical Activity in Musculature (SMAM) in multiple slices in order to improve assessment of the spatial extension of these spontaneous activities. For data validation, diffusion-tensor images (DTI) were acquired with subsequent fiber tractography to fuse anatomical fiber orientation to spontaneous events in DWI. High accordance between both modalities and reliable application of simultaneous multi-slice diffusion-weighted imaging is demonstrated.

Sarah Keller, Jin Yamamura, Shaheen Ahmed, Gerhard Adam, Nancy Rollins, Zhiyue Wang

This study evaluates and compares a pixel-based and ROI-based quantification of DTI-metrics for skeleton muscles in healthy subjects. Besides SNR, an “intra-ROI diffusion direction dispersion angle" is evaluated as a quantitative metric to assess reliability of ROI-based DTI-metrics

HASAN ALSAID, Mary Rambo, Tinamarie Skedzielewski, Alan McDougal, Fritz Kramer, Beat Jucker

The purpose of this study was to longitudinally and non-invasively assess the effect of eccentric contraction induced muscle damage in the Mdx mouse as a model for Duchenne Muscular Dystrophy using non invasive MRI and MRS. Mdx mice showed a significant increase in absolute T2 value at baseline and a severe increase in the exercised leg at Day 2 following injury compared to the Wild type group.  PCr/Pi ratios decreased in the Mdx group acutely upon exercise induced damage and resolved by day 7. The fraction of Undamaged Limb Force is correlated negatively with T2 and positevely with the PCr/Pi ratios.

Rajakumar Nagarajan, Youssef Jaber, Miles Bartlett, Liam Fitzgerald, Julia Miehm, Frank Sup IV, Jane Kent

The goal of this project was to develop an MR-compatible, multi-modal ergometer for the reliable measurement of human skeletal muscle torque, velocity, power and joint angle during 31P MRS studies of knee extensor muscle energetics.  Intracellular [PCr], [Pi] and pH were determined in the vastus lateralis with 4-s time resolution during 4 min of maximal voluntary isokinetic contractions at 240 degrees per second, with a 30 degree range of motion.  High S/N for both the MRS and power data indicate that this tool will be useful in future studies of in vivo muscle bioenergetics.  

Jiufa Cui, Mingqian Huang, Mark Schweitzer

Multifidus muscles (MF) atrophy are common in patients with Low back pain (LBP). Degenerative diseases of the lumbar spine, such as disc herniation, disc degeneration and facet joint osteoarthritis, are leading cause of LBP. Various studies have previously focused on the relationship between MF atrophy and disc degeneration, disc herniation. However, the results are inconsistent. Besides, no study for the correlation between MF atrophy and facet joint osteoarthritis has previously been conducted. This study will investigate the correlation between MF atrophy and disc degeneration, disc herniation, facet joint osteoarthritis using MRI.

Xeni Deligianni, Michele Pansini, Meritxell Garcia, Anna Hirschmann, Arno Schmidt-Trucksäss, Oliver Bieri, Francesco Santini

Stimulation of the quadriceps muscle group of the thigh and synchronous phase contrast imaging at a 3T MRI scanner were applied to six healthy volunteers, to assess repeatability of the dynamic strain and strain rate maps. The repeatability was higher for strain (ICC=0.665-0.751) than for strain rate (ICC=0.242-0.571) and the correlation of the results increased with longer intra-scan rest periods. In conclusion, strain and strain rate measured with synchronous MRI of EMS-controlled muscle contraction are repeatable, though attention should be paid to intra-stimulation rest periods. 

Martin Schwartz, Guenter Steidle, Petros Martirosian, Ander Ramos-Murguialday, Alto Stemmer, Bin Yang, Fritz Schick

Spontaneous mechanical activity in musculature (SMAM) can be observed from time to time in diffusion-weighted images (DWI) of the human lower leg. In DWI, motion sensitivity is usually restricted to a time window between diffusion-sensitizing dephasing and rephrasing gradients. Capabilities to detect SMAM occurring outside this time window by DWI are expected to be clearly reduced. The temporal sensitivity of diffusion-weighted sequences to SMAM is evaluated by varying diffusion-sensitizing time. In addition, concurrent surface electromyography (sEMG) measurements were performed in order to reveal the temporal correlation of the events in both modalities.

Luuk Voskuilen, Valentina Mazzoli, Jos Oudeman, Ludi Smeele, Alfons Balm, Ferdi van der Heijden, Martijn Froeling, Gustav Strijkers, Aart Nederveen

Tongue muscle architecture is suspected to be important in the prediction of speech and swallowing complications after surgery. The tongue contains areas of crossing muscle fibres unable to be resolved by diffusion tensor imaging (DTI). We show that constrained spherical deconvolution (CSD) is able to distinguish these crossing fibres ex vivo and in vivo using a clinically acceptable scan time of 10 min. Also, we show improved tractography in CSD compared to DTI, allowing segmentation of different tongue muscles which conforms to known anatomy.

Alexandra Grimm, Heiko Meyer, Mathias Nittka, Esther Raithel, Oliver Chaudry, Andreas Friedberger, Michael Uder, Wolfgang Kemmler, Klaus Engelke, Harald Quick

Intramuscular adipose tissue directly affects physical performance. 56 subjects (80 ± 5 yrs) with sarcopenia and 23 physically well-trained subjects (28 ± 4 yrs), all male, were examined at the thigh on a 3T MR system using quantitative MRI and MRS sequences. The results show that the use of spectroscopy involves challenges with regard to representative assessment of the entire muscle and might overestimate fat in low-fat tissues as muscle tissue. Furthermore, 2pt in comparison to 6pt Dixon sequences should be used with caution for quantitative evaluation, while multi-echo Dixon sequences are capable of quantifying intramuscular adipose tissue.

Toshiaki Oda, Vadim Malis, Taija Finni, Shantanu Sinha

The relative contributions of the four compartments of the quadriceps to force production are clinically very important information. The spatial and temporal heterogeneity of velocity and strain, (surrogate biomarkers of neural activation) was determined, within and between different compartments of normal quadriceps and along the proximo-distal (Z) axis, during isometric contraction using gated VE-PC imaging. Statistically significant differences were determined, within the same muscle compartment, across compartments and between different Z axis positions. Determining how these change in the diseased state e.g. post-ACL tear will be important in tailoring rehabilitative strategies, with particular relevance to preventing early onset of osteoarthritis.

Alexander Gussew, Martin Krämer, Kevin Moll, Jürgen Reichenbach

We present a new ³¹P-MR spectroscopy pulse sequence, the so called Multi-SliCe-Localized-Excitation approach (MUSCLE), which enables time resolved, interleaved non-spin-echo acquisitions of spectra in multiple muscle slabs. The accuracy of slab selection was successfully verified at 3 T by in vitro measurements in a multiple compartment phantom as well as by in vivo measurements of moderately loaded human calf muscles.

Teresa Gerhalter, Pierre-Yves Baudin, Noura Azzabou, Eriky Caldas, Harmen Reyngoudt, Pierre Carlier, Benjamin Marty

Muscle water T2 is currently being used to assess and monitor the pathology of neuromuscular disorders. The vascular signal of water T2 is close to the one of fat, which might have an impact on the fat fraction quantification using a 2-component fitting approach on MSME data. Here, we examined the impact of long water T2 variations during exercise on fat quantification using the 2-component extended phase graph (EPG) model. Exercise increased the short T2 and the ratio between the amplitudes of short and long T2 signals suggesting an impact of the vascular space on the fat fraction quantification.

Sarah Schlaeger, Elisabeth Klupp, Dominik Weidlich, Barbara Cervantes, Marcus Deschauer, Benedikt Schoser, Sarah Bublitz, Federica Montagnese, Christoph Katemann, Hendrik Kooijman, Ernst Rummeny, Claus Zimmer, Jan Kirschke, Dimitrios Karampinos

The assessment of fatty infiltration and edema in the whole body musculature of patients with neuromuscular diseases typically requires the separate performance of a T₁-weighted sequence and a fat suppressed T₂-weighted sequence. T₂-weighted Dixon TSE enables the generation of T₂-weighted fat-separated and water-separated images, which could be used to simultaneously assess fatty infiltration and edema and to reduce total scan time. The present study examines the diagnostic performance of whole body T₂-weigthed Dixon TSE imaging in 10 patients with neuromuscular diseases.

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

Emerging evidence suggests that intermuscular fat (IMF) accumulation is associated with reduced muscle quality and increased risk of physical limitation. However, the impact and mechanism of IMF in sarcopenia or sarcopenic obesity (SO) are still unclear. MRI is a promising tool for early detection of sarcopenia and SO. This may translate to use in clinical trials and in future clinical practice, where quantitative assessment may become standard of care.  . This study aims to study a new index that we term “IMF density”, shows promise as an important quantitative variable that reflects patients’ physical performances.

Takamasa Sugiura, Toshimitsu Kaneko, Tomoyuki Takeguchi, Kensuke Shinoda, Takuya Fujimaki, Hiroshi Takai

For high quality knee MRI image acquisition, the coil must be centrally aligned with the knee. However, precise alignment can suffer from patient motion and is currently performed by eye. We propose a method to automatically measure the misalignment between coil and knee to alert the clinical operator. This is done by calculating the distance between the coil and the knee joint gap by processing the localizer image with a machine learning technique, which was achieved with a mean accuracy of 3.3 mm. Our experiments further indicated a safe margin for knee-to-coil misalignment within a threshold of 20 mm.

Neil Kumar, Cesar Netto, Lew Schon, Jan Fritz

We demonstrate the negative effects of increasing echo train lengths on total implant-related artifact in a setting of controlled bandwidth, echo spacing and effective echo time. For the practical purpose of metal artifact reduction sequence MR imaging with use of turbo spin echo pulse sequences, high receiver bandwidth can be recommended as the first line means, whereas long echo train length may not be recommended and used cautiously due to the potential of substantial degradation of image quality.

Jan Fritz, Benjamin Fritz, Gaurav Thawait, Wesley Gilson, Christoph Forman, Esther Raithel, Mathias Nittka, Robert Sterling, Paul Khanuja

Because susceptibility artifacts increase with field strength, MRI of knee arthroplasty implants is commonly performed at 1.5T. However, 3T MRI offers substantially higher SNR and may be the only available option. SEMAC can achieve substantial metal artifact reduction at 3T, but requires prolongs scan times. Capitalizing on the inherent sparsity of SEMAC data, compressed sensing-based pseudo-randomized undersampling and iterative reconstruction can substantially accelerate data acquisition. We show the clinical feasibility of highly accelerated 3T MRI of CoCr knee arthroplasty implants using a compressed sensing SEMAC TSE sequence with metal artifact reduction capabilities and acquisition times similar to 1.5T.

Anthony Tadros, Justin West, Amin Nazaran, Ya-Jun Ma, Heinz Hoenecke, Jiang Du, Eric Chang

Lamellar bone is poorly evaluated using conventional magnetic resonance (MR) imaging secondary to its inherently short T2 relaxation time. Rather, the contours of lamellar bone are often inferred based on marrow signal. In the setting of shoulder instability or pre-operative planning for arthroplasty, rotator cuff integrity and glenoid bone defects are frequently assessed using both MRI and computed tomography (CT), respectively. An MR imaging technique to directly image lamellar bone could potentially eliminate the need for a CT scan and be particularly useful for young patients with acute shoulder instability.

Alexandra Cristobal-Huerta, Dirk Poot, Mika Vogel, Juan Hernandez-Tamames

Accelerated 3D-FSE using Compressed Sensing (CS) with a 30% scanning time reduction has been recently introduced and evaluated for knee MR images. 3D-GRASE is a hybrid FSE-EPI sequence that can achieve higher time-efficiency scans, since it acquires more k-space data per refocusing pulse. The purpose of this work is to present CS 3D-GRASE to achieve even faster musculoskeletal MRI acquisitions.

Bénédicte Delattre, Maria Vargas, Sana Boudabbous

Synthetic MRI is a very promising method to generate different contrasts used in clinical practice from quantitative T1, T2 and PD measurements. In this study we confirmed the feasibility of Synthetic MR in knee examinations, allowing generation of T1, PD and STIR images in faster time than conventional imaging with appropriate quality and good diagnosis confidence.

Feifei Gao, Yinghui Ge, Yi Wei, Shufang Wei, Xiaojing Kan, Panli Zuo, Dingxin Wang, Tianyi Qian

The turbo spin echo sequence is one of the most frequently used MR sequences in routine musculoskeletal exams. Its short scan time has allowed it to become a popular clinical choice because it reduces the possibility of motion artifact especially in patients with low tolerance for MR exams. In order to further shorten the scan time and increase temporal and/or spatial resolution, simultaneous multi-slice technique has been widely applied during brain image acquisition. In this study we tried to apply a prototypical SMS-TSE sequence to hand and foot imaging. Compared to the standard TSE sequence, the SMS-TSE had the same image quality and a shorter acquisition time. 
 

Gaspar Delso, Michael Carl, Graeme McKinnon

The objective of the present study was to improve three-dimensional visualisation of ZTE-based bone images by incorporating a-priori anatomical information in the rendering process. 

Mayuko Haraikawa, Masashi Suzuki, Yuki Hara, Kayu Takezawa, Nanami Okano, Iichiro Osawa, Kaiji Inoue, Eito Kozawa, Junji Tanaka, Keisuke Watarai, Taishi Unezawa, Atsushi Kondo, Hiroshi Imai, Thomas Beck, Dingxin Wang, Mamoru Niitsu

Simultaneous-Multi-Slice Turbo-Spin-Echo (SMS TSE) protocols were added to our conventional (CNV) hip joint MR examination in 21 patients. Image quality of acetabular labrum, articular cartilage, round ligament and bony trabeculae were evaluated by three reviewers and showed comparable image quality, whereas SMS was slightly better for bony trabeculae. If CNV is substituted by SMS, total scan time can be reduced by approximately 40%. Although SMS protocols showed higher specific absorption rate (SAR), it only accounted for 20% of scans which exceeded the first level of SAR limit. SMS could be applied to clinical examination with advantage of acquisition time reduction.

Xeni Deligianni, Christopher Klenk, Meritxell Garcia, Michele Pansini, Anna Hirschmann, Arno Schmidt-Trucksäss, Oliver Bieri, Francesco Santini

Stimulation of the quadriceps muscle group of the thigh and synchronous phase contrast imaging at a 3T MRI scanner were applied to six young and 13 elderly volunteers, to assess age-related differences. Dynamic strain and strain rate maps were reconstructed. Age-related differences both for strain and strain rate were observed and the significance of the difference increased when the vastus intermedius muscle was included. 

Aiming Lu, Joel Felmlee, Krzysztof Gorny

MR imaging with UTE/ZTE sequences has attracted significant clinical interest in recent years due to their many inherent merits, such as resilience to motion and flow artifacts, capability to achieve high acceleration factors and minimize acoustic noise, as well as capability to capture signal from tissues with ultra-short T2s/T2*s. However, ZTE acquisitions and many UTE acquisitions require the use of low flip angles and, as a consequence, deliver mostly proton density weighted contrast. Magnetization preparation such as fat suppression with UTE/ZTE is time consuming as k-space center data needs to be acquired every TR. Therefore, exploiting the other inherent information such as signal phase is important. In this work, we demonstrate that phase images obtained with UTE can be exploited to enhance the tissue contrast such as fat/water differentiation and enable improved cortical bone visualization, and generate susceptibility map in the volunteer knee on a clinical scanner at 3T. 

Takayuki Sakai, Masami Yoneyama, Atsuya Watanabe, Iain Ball, Toshiaki Miyati, Noriyuki Yanagawa

Diffusion-sensitized driven-equilibrium with phase-cycling T1-turbo field-echo (pc-DSDE) enables the visualization of peripheral nerves. However, pc-DSDE has several problems, such as low image stability, poor reproducibility, and partially remaining venous signals.  To solve these problems, we improved DSDE pre-pulse module (iDSDE) including B1-insensitive RF pulse and orthogonally combined motion- and diffusion-sensitized gradient scheme.  iDSDE showed better visualization of peripheral nerves without contamination of veins.

S Kaushik, Andrew Huettner, Peter LaViolette, Andrew Nencka, Kevin Koch

A nonlinear iterative optimization algorithm was used to design an adiabatic inversion pulse with a bandwidth of 3.2 kHz. With a larger bandwidth, the new pulse maintains the same SAR as the original inversion pulse and also has an improved spectral profile. Images obtained on a phantom, and in-vivo, show improved fat suppression, and reduced ripple artifacts in the slice domain. In addition to improving image quality, the optimized RF pulse may improve the diagnostic ability of STIR with 3D multi spectral imaging.  

Paul Weavers, Matt Frick, Erin Gray, David Stanley, Joshua Trzasko, Shengzhen Tao, Yunhong Shu, Derrick Doolittle, John Huston III, Thomas Foo, Matt Bernstein

A compact, low-cryogen 3T MRI system with high-performance gradients has been developed and tested on healthy volunteers. This compact 3T MRI unit has the potential to dramatically impact MRI by offering simplified siting and strong gradient performance at lower cost. In addition to brain and pediatric imaging, the scanner offers an ideal platform for musculoskeletal (MSK) imaging of the extremities. 

Sunghoon Park, Young Ju Lee, Sung-Min Gho, Seungnam Back, Kyu-Sung Kwack

Synthetic MR is able to acquire T1-, T2-, proton density-weighted image and quantitative map simultaneously and has the potential to reduce the overall examination time. Synthetic MR image have comparable image qualities with that of conventional MR images for the knee joint.

Sergey Magnitsky, Jaskanwaljeet Kaur, Yu-An Evan Lay, Geetha Mohan, Jinjin Zhang, Djaudat Idiyatullin, Michael Garwood, Nancy Lane

Mesenchymal Stem Cells (MSCs) have high potentials for a treatment of bone diseases. T2*w-MRI in combination with iron labeling of MSCs has shown promising results for the detection of therapeutic cells. However, this method is not applicable for the detection of MSCs in knee joints because both the iron labeled cells and bones produce a hypointense signal. We have shown that the SWIFT sequence overcomes this limitation and generates a distinct and quantifiable signal from iron labeled cells in a knee joint in vivo. Proposed protocol opens new opportunities for in vivo monitoring of cell therapy of bone disorders.

Yoshikazu Okamoto, Kiyoshi Maehara, Kenta Tanaka, Tetsuya Kanahori

This presentation clarified the clinical interpretation of 'asymptomatic MCL injury of the elbow observed on MRI among adolescent baseball players' by comparing the findings of MRI with those of standard clinical orthopedic examinations including palpation and US. Our results suggested the finding  includes a broad spectrum of injuries; namely, a group of injuries that are characterized by changes associated with 'adaptation' and group of a 'pre-injury' characterized by changes to symptomatic MCL injury.

Keizo Tanitame, Takahiro Sueoka, Yukiko Honda, Yuji Takahashi, Akira Naito, Kazuo Awai

Radial images through the center of the acetabulum in the plane including the entire acetabular rim are useful for evaluating acetabular labral injuries, and those perpendicular to the center of the femoral head through the central axis of the femoral neck enable evaluation of the morphological findings of femoroacetabular impingement. Continuous thin-slice images from optimized 3D fat-suppressed multi-echo gradient-recalled-echo allow 360° radial reformation of hip joints, offering precise evaluation of the range of acetabular labral injury and femoroacetabular impingement morphology.

yujiao zhao, zhizheng zhuo, wen shen

Currently, the abnormal morphology of LAM is assessed with an unaided subjective diagnosis. But T2 mapping can quantitatively evaluate the injury muscle and indicate the injured degree and region of the LAM. In this study, we investigate whether the quantitative MR T2-mapping can evaluate birth-related levator ani muscle injury. The results showed that T2-mapping can quantitatively assess birth-related levator ani muscle injury and T2-mapping color-coded images show the range and degree of LAM injury visually. Moreover, it is helpful for detecting micro lesions which is difficult for just using PDWI images.

Shufang Wei, yinghui Ge, Xiaojing Kan, Feifei Gao

T2 mapping imaging, as one of the MRI functional imaging, is sensitive to the changes of early cartilage components in the early stage of HA, hinting that T2 mapping imaging may be used as a tool to diagnose the cartilage disease in the early stage of HA.

Hyungseok Jang, Fang Liu, Richard Kijowski, Alan McMillan

T2* analysis is used in musculoskeletal imaging to characterize tendon, meniscus, and cartilage in human joints. With the development of high performance gradient systems, ultrashort time echo (UTE) imaging has become more feasible, allowing robust bi-component of short and long T2* tissue components. Many studies have been performed to realize robust and clinically feasible bi-component T2* imaging, but the long acquisition time required to obtain multiple echo images remains challenging. In this study, we propose a novel, rapid imaging scheme for bi-component T2* analysis, based on ramped hybrid encoding (RHE) that allows robust bi-component T2* estimation within a single scan.

Daehyun Yoon, Brian Hargreaves

Previous studies with nerve samples have demonstrated the existence of multiple signal components with different T2 or T2* relaxation times in peripheral nerves. The short- T2* signal component has received significant research attention, based on its correlation with myelin health of nerve fiber in many neurological diseases. However, little research has been conducted with in vivo human scans to separate the short-T2* component and the long-T2* component in peripheral nerves. Using a 3D ultra-short echo time (UTE) cones sequence, we demonstrate the feasibility of capturing and separating both bi-exponential T2* signal components from in vivo human nerve scans

Lin Yuan, Zha Yunfei, Lin Hui, Wu Bing

    To explore the effect of type 2 diabetes on bone marrow fat contnent(BMF) and marrow blood flow, as well as the association of the bone marrow fat contnent and marrow perfusion in type 2 diabetes mellitus (T2DM) patients. 26 healthy nondiabetic subjects and 24 T2DM patients underwent lumbar IDEAL-IQ and DCE-MRI. The marrow fat content(BMF) and the marrow perfusion parameters (Ktrans, Kep, Ve) of lumbar vertebra all showed significant difference between T2DM patients and the healthy individuals. In addition, transfer constant (Ktrans) was negatively correlated with BMF in T2DM patients. 

Naoki Ohno, Tosiaki Miyati, Shuto Suzuki, Hirohito Kan, Toshitaka Aoki, Yoshitaka Nakamura, Yuki Hiramatsu, Toshifumi Gabata

In general, it is difficult to obtain functional information about water and lipid in tissues at the same time. We, therefore, developed a novel method using chemical shift displacement and recovery-based separation of lipid tissue (SPLIT) with different inversion times, echo times, and b-values to simultaneously acquire diffusion, perfusion, T₁, T₂, and lipid fraction in the calf. All parameters obtained with the SPLIT were consistent with previously reported values. This method enables simultaneous acquisition of functional information without special pulse sequence.

Jakob Örtegren, Pernilla Peterson, Jonas Svensson, Carl Tiderius

The longitudinal effects of Slipped Capital Femoral Epiphysis (SCFE) on hip cartilage integrity and hip function are poorly understood. In this study, 44 hips were evaluated with delayed Gadolinium-enhanced MRI of cartilage (dGEMRIC) in average 11 years after SCFE. A low dGEMRIC index was detected in SCFE hips compared to unaffected hips, with gradually lower dGEMRIC index anteriorly in the hip joint. Furthermore, a low dGEMRIC index correlated both with impaired hip function and femuroacetabular impingement (FAI), which further strengthens the theory of FAI as a mediator of osteoarthritis after SCFE.

Jose Raya, Uran Ferizi, Amparo Ruiz, Steven Abramson, Jenny Bencardino, Svetlana Krasnokutsky Samuels

The objective of this work was to investigate differences in cartilage matrix composition and structure across subjects with different stages of OA severity and test if the changes in the collagen network are concomitant or subsequent to the changes in proteoglycan.

Yinghua Zhao, Yajun Ma, Michael Carl, Xing Lu, Yanchun zhu, Eric Y Chang, Jiang Du

The zone of calcified cartilage (ZCC) is a thin layer between articular cartilage and bone. The ZCC plays an important role in the pathogenesis of osteoarthritis (OA) but has never been imaged in vivo with magnetic resonance (MR) imaging techniques. In this study we aimed to investigate the feasibility of direct imaging of the ZCC in healthy volunteers using a three dimensional (3D) ultrashort echo time (UTE) Cones sequence on a clinical whole body 3T scanner.

Roberto Colotti, Patrick Omoumi, Gabriele Bonanno, Jean-Baptiste Ledoux, Ruud van Heeswijk

The goal of this study was to compare the precision and accuracy of a novel isotropic 3D T₂-prepared gradient-echo T₂ mapping technique (Iso3DGRE) with the clinical standard 2D multi-slice turbo spin-echo (MS-TSE) for T₂ mapping of knee cartilage at 3T. A phantom study was performed to determine the accuracy of both techniques against the reference standard spin echo (SE). T₂ mapping of knee cartilage was then performed in 13 healthy volunteers and 5 patients with late-stage osteoarthritis. Compared to MS-TSE, Iso3DGRE T₂ mapping resulted in T₂ values with equivalent precision and slightly higher accuracy at a higher spatial resolution.  

Ashley Williams, Matthew Titchenal, Constance Chu

This work examines the use of UTE-T2* profile analysis to assess sub-surface knee cartilage structural changes in 26 ACL-reconstructed subjects and compares UTE-T2* metrics to kinetic and kinematic measures of walking. UTE-T2* profile characteristics detect differences between ACL-reconstructed and uninjured knees. Side-to-side differences in an individual’s UTE-T2* profile metrics correlate with side-to-side differences in their gait metrics. The results suggest that UTE-T2* profile characteristics of cartilage are a useful metric for identifying cartilage subsurface changes early after ACLR and may reflect matrix changes resulting from altered loading.

Marcus Raudner, Tom Hilbert, Tobias Kober, Vladimir Juras, Ewald Moser, Claudia Kronnerwetter, David Stelzeneder, Siegfried Trattnig

The quantitative measurement of the T2 relaxation time has been shown to be a useful tool for radiological diagnosis. However, the use of quantitative MRI (qMRI) in clinical routine is often hindered due to long acquisition times. Here, we assess T2 parameters in the lumbar and cervical spine as well as the knee using GRAPPATINI, a model-based accelerated T2 mapping sequence. Additionally, synthetic T2-weighted (T2w) images are derived from the quantitative maps. The T2 maps and synthetic T2w images are compared to conventional T2w and T2 mapping sequences, yielding an overall 5.8-fold time-saving.

Mustapha Bouhrara, David Reiter, Kyle Sexton, Christopher Bergeron, Linda Zukley, Richard Spencer

We demonstrate the clinical feasibility of high-resolution (HR) in-vivo mapping of proteoglycan water fraction (PgWF) in human knee cartilage by combining the mcDESPOT protocol for data acquisition and Bayesian Monte Carlo (BMC) analysis for data analysis. For all subjects, PgWF maps derived from low resolution datasets exhibited partial volume and magnetic susceptibility effects leading, respectively, to an overestimation and an underestimation of PgWF values in several cartilage regions. These issues were absent in HR PgWF maps. Further, BMC-mcDESPOT demonstrates high reproducibility and stability in the estimation of PgWF as compared to the conventional stochastic region contraction (SRC) algorithm.

Michael Carl, Amin Nazaran, Jiang Du, Graeme Bydder

The T₂ relaxation of MRI signals is an important parameter in assessment of pathology. Here we analyze the effects that Fat Saturation pulses of various bandwidths have on the values of T₂quantification. We found that Fat Saturation can have a notable effect on the measured T₂ values of multi-component tissues. Since the dispersion is less for smaller FS bandwidths, longer FS pulses can help to minimize the effects.

Xin Cheng, Yajun Ma, Eric Y Chang, Jiang Du

In this study, we aimed to evaluate UTE-MT derived macromolecule fractions in articular cartilage subject to sequential collagenase enzymatic treatment. The preliminary result suggests that UTE-MT imaging and signal modeling allows for quantitative evaluation of macromolecular fractions in articular cartilage. Furthermore, results from UTE-MT imaging and signal modeling are insensitive to the magic angle effect, which is a huge advantage over the conventional T2 and T1rho measures. The water and macromolecular changes in both short and long T2 tissues in the knee joint using UTE-MT provides a “whole-organ” approach, and may be useful in the diagnosis and treatment of OA.

Ashley Williams, Matthew Titchenal, Constance Chu

Identification of patients with early cartilage degeneration who are at greater risk for poor clinical outcomes is critical for development of interventions to reduce osteoarthritis risk after ACL injury. This study tested the hypothesis that UTE-T2* profile analysis of knee cartilage correlates with patient reported outcomes (PRO) in ACL-reconstructed subjects 2 years after surgery. UTE-T2* mean values and profile characteristics in 27 ACL-reconstructed subjects correlated with patient reported pain and symptoms. Side-to-side differences in UTE-T2* profiles of some high functioning individuals suggest that this UTE metric may provide earlier warning of cartilage at risk for progressive degeneration than PRO.  

Markus Schreiner, Sebastian Apprich, Vladimir Mlynarik, Pavol Szomolanyi, Martin Zalaudek, Benedikt Hager, Vladimir Juras, Michael Weber, Reinhard Windhager, Siegfried Trattnig

Assessment and adequate treatment of articular cartilage lesions are a common challenge in clinical orthopaedic routine. To allow for better disease prediction and thus evidence-based treatment selection, there is a strong need for objective predictive markers. In this study we demonstrate the predictive potential of T2 mapping in the assessment of untreated patellar cartilage lesions over an average follow up time of four years.

Markus Schreiner, Kitty Ohel, Livnat Ben-Zur, Sebastian Röhrich, Martin Zalaudek, Pavol Szomolanyi, Vladimir Juras, Vladimir Mlynarik, Reinhard Windhager, Siegfried Trattnig

The treatment of femoral cartilage lesions still remains a challenge. Established cartilage repair techniques include microfracture (MFX), acellular scaffolds and cell based therapies such as ACI and MACI, which differ in associated morbidity and outcome. Therefore, there have been strong research efforts to develop novel treatment alternatives. In this study, we demonstrate that GelrinC, a novel acellular biodegradable implant, allows a successful treatment of both chondral and osteochondral femoral lesions in a minimal invasive one-step procedure. For both lesion types a substantial improvement of MOCART scores as well as T2 values has been demonstrated over a 24-month period.

Paul de Heer, Robert Hemke, Cristina Lavini, Jasper Schoormans, Bram Coolen, Anouk Barendregt, Gustav Strijkers, Mario Maas, Jaap Stoker, Aart Nederveen, Jurgen Runge

Juvenile Idiopathic Arthritis (JIA) is the most common rheumatic disease in childhood and represents one of the leading causes of pediatric acquired disability. The aim of our study was to evaluate feasibility of high spatiotemporal resolution GRASP DCE-MRI in children with JIA and secondly to compare image quality between GRASP and conventional DCE-MRI in evaluating synovitis. In this pilot study, GRASP DCE-MRI proved to be feasible in a child with JIA. Moreover, for the evaluation of synovitis significantly higher spatial resolution and much cleaner signal-enhancement plots could be obtained using GRASP compared to conventional DCE-MRI.

Hon Yu, Alex Luk, Jimmy Ton, Edward Kuoy, Jeff Russell, Kelli Sharp, Hiroshi Yoshioka

This study demonstrates an angular-dependent T2 and T1ρ profile of talar dome cartilage at 3T using novel angular-segmentation methodology for the potential of quantitative functional assessment of cartilage in vivo. The results in this study indicate T2 values over the posterior weight-bearing portion were higher in young dancers than age-matched healthy volunteers even though cartilage thickness and volumes were not significantly different between two cohorts.

Gerd Melkus, George Grammatopoulos, Kawan Rakhra, Paul Beaulé

In this study, we investigated whether the T1ρ profile of the hip cartilage changes over time in a subject group with asymptomatic cam-type femoroacetabular impingement (FAI). After the initial T1ρ data acquisitions, the scans were repeated on the same group in a mean time interval of 3.3 years. For the majority of the subject group there were no significant T1ρ changes in the whole joint and in different hip cartilage regions. However, 1 patient (out of 12) showed significant (>20%) increased T1ρ values (i.e. proteoglycan reduction).

Dongyeob Han, Taehwa Hong, Dong-Hyun Kim

Magnetic resonance fingerprinting (MRF) provides rapid quantification of proton density, T1 and T2 mapping using spiral acquisition. However, for high resolution imaging, spiral imaging can be limiting due to its relatively long readout time. In this study, we implemented high resolution (0.5x0.5mm²) MRF-FISP using golden angle random rotating radial acquisition.

Shan Wang, Cui-Ping Ren, Jing-Liang Cheng, Zhi-zheng Zhuo

We tried to evaluat  OA by using the T2 mapping and the texture characteristics. Thirty-seven patients and sixteen healthy volunteers were recruited in this study. The results showed that the T2 value is higher in patients than in controls and some texture characteristics in two groups are different. It can be concluded that texture analysis combined with T2 maping are an useful tool for diagnosis of OA patients.

Nina Hänninen, Jari Rautiainen, Lassi Rieppo, Simo Saarakkala, Mikko Nissi

Classical and several rotating frame quantitative MR relaxation parameters have been used for evaluation of composition and structure of articular cartilage, and demonstrated to have variable sensitivity to orientation of the tissue in magnetic field. The orientation dependence of several relaxation parameters in articular cartilage have been previously investigated and were now further analyzed and compared to polarized light microscopy results. T₁, adiabatic T_1ρ with HS1 pulse and CW-T_1ρ at 2 kHz spin-lock demonstrated the least orientation dependence. Usefulness of the parameters for osteoarthritis diagnostics, as reported in the literature, was evaluated together with the orientation sensitivity.

Feliks Kogan, Evan Levine, Uchechukwuka Monu, Akshay Chaudhari, Garry Gold, Brian Hargreaves

Osteoarthritis (OA) is commonly a bilateral disease. While long scan time and costs have precluded separate scanning of both knees in clinical MRI, there is evidence that bilateral examinations are beneficial for evaluation of OA changes, especially for longitudinal studies. In this study, we demonstrate the feasibility of simultaneously imaging both knees with similar scan time, SNR, and quantitative accuracy compared to single knee acquisitions.

Grayson Tarbox, Joseph Valentine, Meredith Taylor, Neal Bangerter

Balanced steady-state free precession imaging using the elliptical signal model geometrical solution can be combined with a GRAPPA parallel imaging reconstruction that preserves phase information to shorten scan times.

Daniel Park, Scott Fernquest, Antony Palmer, Marija Marcan, Irina Voiculescu, Siôn Glyn-Jones

Physiological Magnetic Resonance imaging (pMRI) offers the potential of diagnosing osteoarthritis at a stage where patients may benefit from intervention, and acting as an assay of disease to test the efficacy of novel early intervention treatments. pMRI data, however, requires segmentation to allow morphological and biochemical quantitative analysis. Manual segmentation is time consuming and a viable automated segmentation method in the hip remains elusive. We have produced a fast, accurate, and reproducible semi-automated method of segmentation to allow wider implementation of pMRI for use in quantitative analysis of early OA in the hip in both research and clinical settings.

Jose Raya, Amparo Ruiz, Uran Ferizi

We aim to perform a meta-analysis of the corpus of experimental results accumulated for compositional MRI biomarkers of articular cartilage used in clinical studies. We summarized the data according to the statistical evidence that is reported. We report the correlation of MRI parameters with composition, the ability of MRI parameters to detect group differences between healthy and degraded cartilage, and the ability of MRI to detect cartilage damage.

Hon Yu, Alex Luk, Jimmy Ton, Edward Kuoy, Jeff Russell, Kelli Sharp, Hiroshi Yoshioka

This study demonstrates feasibility in manual segmentation of talar dome using MRI of the ankle and provides a systematic approach in assessment of image-based segmentation utilizing purely geometrical attributes and subsequent validation of angle-dependent analysis of T2 and T1ρ mapping of the cartilage. The results clearly demonstrates the magic angle effect of the talar dome cartilage on T2 mapping and also the important fact that repeatability assessment of segmentation should be made using the geometrical attributes rather than the underlying segmentation-based quantity.

Aditi Guha, Ashley Williams, Constance Chu

The purpose of this study is to establish the reliability of the UTE-T2* mapping method using 3DCones sequence shown to detect subsurface changes in knee cartilage and meniscus. Scans were performed on cadaver knee specimen using 3DCones acquisition at 3T with 8 and 12 TEs. Reliability was assessed by the intraclass correlation coefficient (ICC) calculated as 0.77 and 0.91 for the 8 and 12 point techniques. The method is good to excellently reproducible for both techniques. Hence, the 3DCones UTE-T2* mapping technique can reliably evaluate subsurface changes in meniscus and cartilage and help identify at-risk OA patients.

Aiming Lu, Krzysztof Gorny, Mai Lan Ho, John Huston, Robert Witte, John Lane, Dan Rettmann, Michael Carl, Gaspar Delso

Using MRI for depicting solid cortical bone structures is of increasing clinical interest. Due to its low water content and short transverse relaxation time, cortical bone appears as signal void in conventional gradient echo or spin echo pulse sequences. This allows “black bone” techniques to be used when air does not confuse the visualization of cortical bone. In cases differentiation between bone tissues and ai are desired “bright bone” techniques  utilizing Ultrashort echo time (UTE) or Zero TE (ZTE) MRI-have been proposed. Long T2-suppression methods (e.g., echo subtraction, long T2 saturation) are often applied to generate positive cortical bone contrast.  However, clinical applications of these methods are still limited due to significant increase in acquisition time and reduced SNR efficiency.  Recently a prototype proton density (PD)-weighted, zero TE (ZT) sequence has been demonstrated clinically. This work aims to improve the bright bone MRI using the ZTE sequence by optimizing the bone signal during data acquisition, minimizing partial volume effect with ultra high resolution data acquisition and optimizing the image processing for better bone/air differentiation.

Amin Nazaran, Michael Carl, Yajun Ma, Saeed Jerban, Yanchun Zhu, Eric Chang, Jiang Du

Ultra short echo time (UTE) techniques have been used to image cortical bone. However, imaging cortical bone in hip has been challenging due to limited signal-to-noise ratio (SNR), robust long T2 suppression, and long scan time. UTE sequences with TEs down to 32μs are able to acquire signal from both short and long T2* tissue. To suppress long T2* tissue, the combination of inversion recovery (IR) and UTE imaging can be used. In this report, we applied three-dimensional adiabatic inversion recovery prepared UTE with Cones trajectories (3D IR-UTE-Cones) to suppress long T2 tissue and to directly quantify cortical bone in the hip in vivo at 3T.

Atena Akbari, Shahrokh Abbasi-rad, Amirali Kazeminejad, Hamidreza Saligheh Rad

MR structural imaging is proved to be able of featuring cortical bone hierarchical structure by obtaining enough signal from hydrogen protons of short T₂^* components of bone. Extreme variability of free water quantities found in cortical bone pores during aging or bone disease, furnishes researchers with a great source of information to inspect bone health. In this study, we employed short time of echo MR imaging approach to quantify cortical bone free water T₁ in different regions of tibia to extract the porosity distribution pattern of cortical bone and its alteration with age in eight healthy volunteers.

kejun wang, Yunfei Zha, Xiao Xu

This study is to investigate whether adipocytes influence bone marrow microcirculation based on DCE-MRI and ex vivo high-resolution MAS 1H NMR spectroscopy. In this animal review committee-approved study, Rat Femurs were evaluated through DCE-MRI, 1H HRMAS NMRS, and histopathologic analysis before irradiation and on days 4 and 7 after irradiation. The results showed Ktrans and adipocytes gradually increased a peak on the 7th day after irradiation. In conclusion, bone marrow microcirculation permeability correlation with fat content after irradiation suggested for the first time that a pathophysiology mechanism based on fat- vascular permeability in the injury of bone marrow microcirculation.

Arash Latifoltojar, Margaret Hall-Craggs, Alan Bainbridge, Neil Rabin, Rakesh Popat, Ali Rismani, Kwee Yong, Shonit Punwani

Quantitative MRI assessment of treatment response using advanced novel imaging techniques have shown promises for monitoring outcome in patients with symptomatic multiple myeloma (MM), undergoing intensive chemotherapy.

In this work we are investiagting the potential of whole-body mDixon MRI's signal fat fraction early changes  as a prognostic imaging biomarker for long-term follow-up of MM patients. 

Dimitri MARTEL, Benjamin LEPORQ, Mary BRUNO, Sean BOONE, Gregory CHANG

Recent studies have shown skeletal variation of bone marrow adipose tissue (bMAT) and its role in bone remodeling. Our aim was to assess the variation in bMAT composition in five regions within the proximal femur in both controls and OP patients using a chemical shift encoded (CSE) imaging technique.

Stefan Ruschke, Andreas Hock, Dominik Weidlich, Ernst Rummeny, Jan Kirschke, Thomas Baum, Roland Krug, Dimitrios Karampinos

The assessment of vertebral bone marrow fat unsaturation is attracting growing interest for applications in bone metabolism and osteoporosis. Especially in younger subjects, the presence of a strong and broad water peak confounds the extraction of surrounding peaks (olefinic and glycerol peaks), which are used for the determination of fat unsaturation. Inversion-recovery spectroscopy allows the extraction of these peaks by differentiating the signals based on different T1 relaxation times between water and fat. The feasibility of using inversion-recovery spectroscopy was evaluated in a phantom experiment in comparison with gas chromatography and in vivo in four young and healthy volunteers. 

bing xie, jingjing li, jie wang, mingshan du, wei chen, Xiaoyue zhou, Panli zuo, Xiaodong zhong

 Avascular necrosis of thefemoral head (ANFH) is a pathological process that results from interrupted or impaired blood supply to bone. The multi-echo 3D Dixon technique provides the water/fat ratio quantification for evaluation of the bone marrow edema and the stage of ANFH. Our study demonstrated that femoral head water/fat permillage in ANFH was significantly higher than that of the healthy hips.

Xiaona Li, Zhigang Peng, Panli Zuo, Yi Sun, Nittka Mathias, Jianling Cui

To compare the clinical detection rates in local lesions using the slice-encoding for metal artifact correction (SEMAC) & view angle tilting (VAT) Turbo Spin Echo (TSE) with the standard TSE sequence in patients with titanium screws. Following surgery, patients with reported discomfort at the operation site were examined with both TSE and SEMAC-VAT TSE imaging. They were also examined by digital radiography (DR) and computed tomography (CT). All images were assessed and scored. Despite the long scan time, SEMAC-VAT TSE reduced metal-induced artifacts and may improve the diagnostic sensitivity compared to standard TSE, DR and CT.

Ying Zhan, Xinwei Lei, Yingying An, Jin Qu, Zhizheng Zhuo

The study was using fat fraction (FF) to investigate the fat deposition of sacroiliitis. 3T MRI with mDIXON Quant technique was performed. All patients were divided into three groups: simple edema group, edema-fat deposition group and simple fat deposition group. The FF of both edema and fat deposition areas were obtained on FF image. The FF of edema areas was higher in edema-fat deposition group than simple edema group. The FF of fat deposition areas was higher in simple fat deposition group than edema-fat deposition group. mDIXON Quant technique could be used for assessing the situation of the disease.

Michael Carl, Graeme McKinnon, Gaspar Delso

Many musculoskeletal tissues such as cortical bone have very short transverse relaxation times and require specialized pulse sequences such as UTE or ZTE for optimal signal acquisition. Recently, these sequences have been used to directly visualize cortical bone by suppressing surrounding long T2 tissues such as fat or muscle by either magnetization preparation using inversion recovery, or logarithmic tissue segmentation. In this work, we compare these techniques on a cadaveric bovine knee specimen. Both inversion recovery UTE as well as tissue segmented ZTE imaging proved promising method for direct bone imaging with CT-like image appearance.

Bernhard Neumayer, Matthias Schloegl, Christian Payer, Thomas Widek, Thomas Ehammer, Rudolf Stollberger, Martin Urschler

The topic of age estimation in living persons is important for sports competitions as well as unaccompanied minors without valid documents and has recently gained interest. Recommended imaging protocols are based on modalities using ionizing radiation and therefore MRI is currently investigated for its eligibility to replace these measurements. This study investigates the accuracy of MRI-based age estimation for retrospectively undersampled data to determine the degree of inaccuracies introduced by an acceleration of the acquisition technique using commercially available undersampling strategies. For this purpose the data is analyzed by a radiologist and using an automatic method.

Jules L. Nelissen, Dorien Verschuren, Larry de Graaf, Cees W. J. Oomens, Klaas Nicolay, Ralph Sinkus, Jurgen H. Runge, Aart J. Nederveen, Gustav J. Strijkers

Skeletal muscle pathology is often accompanied by abnormal fat deposition, fibrosis, and edema. Altered muscle biomechanical properties associated with these compositional changes can be quantitatively assessed with MRE. We present MRE measurements of the gluteus maximus muscle. In healthy volunteers, we have tested reproducibility and correlated the shear modulus G_dto T₂ and fat-fraction FF_dix measured using Dixon. Acceptable intra and inter reproducibility was found. Expected difference in G_d between gluteus maximus and subcutaneous fat was confirmed. Correlation plots of T₂ and FF_dix with G_d showed that MRE can derive biomechanical properties that potentially can provide additional information to characterize skeletal muscle pathology.

Kenneth Wengler, Chien-Hung Lin, Mingqian Huang, Elaine Gould, Mark Schweitzer, Xiang He

Diabetic neuropathy is a leading cause of diabetic foot ulcer and has been shown to be induced by insulin resistance. Itramyocellular lipid (IMCL) measured by MRS in large skeletal muscles has been shown to correlate with insulin resistance. In this study a generalized Lorentzian approximation is used to estimate the IMCL and EMCL frequency shift as a function of muscle fiber bundle orientation. DTI is used to measure the fiber bundle orientation and provide prior information for IMCL/EMCL peak fitting. 2D-CSI is used to quantify IMCL contents in foot muscle groups of healthy subjects and diabetic patients. 

Kevin Moll, Alexander Gussew, Maria Nisser, Steffen Derlien, Jürgen Reichenbach

^31P MR spectroscopy enables a non-invasive evaluation of a metabolic response to a given exercise. A combination of this technique with other methods like ¹H MRS, spirometry and blood lactate diagnostics improves the application field. Therefore, a broad range of metabolic parameters were acquired during an exercise of a single calf muscle to evaluate the effects of local energy demands on global parameters. We observed high adaptations resulting in good correlations between peripheral and locally measured values.

Tan Guo, Bing Wu, Dandan Zheng, Xiaoxiong Wang, Xiaoxia Wang, Yan Song, Min Chen

This study is to investigate and compare the changes of extraocular muscles in patients with active thyroid associated ophthalmopathy shown by T1ρ and T2 maps. The superior differential ability of T1ρ comparing to the currently used T2 mapping is encouraging and the flexibility in exploring the different in spin lock frequencies would be promising tool in evaluating the extraocular muscle changes with thyroid associated ophthalmopathy.

Min A Yoon, Suk-Joo Hong, Chang Ho Kang, Kyung-Sik Ahn, Baek Hyun Kim, In Seong Kim

Purpose: To identify MR parameters that are significantly associated with aging in healthy thigh muscles and investigate age-related characteristics.

Methods: Thirty healthy subjects underwent multi-parametric MRI of the right thigh, including IVIM-DWI, DTI, multi-echo Dixon imaging, DCE-MRI. Parametric maps of the thigh muscles (divided into three compartments) were analyzed. Relationships between parameters and age were assessed with simple and multiple linear regression analyses.

Results: Fractional anisotropy (slope=1.018) and V_e (slope=2.151) in anterior compartment and fat percentage in posterior compartment (slope=2.031) showed significant relationships to age (p<0.05).

Conclusion: Several MRI parameters of the thigh muscles were associated with normal aging.

Lian Ding, Fei Gao, Chengyan Wang, Wenjian Huang, Jue Zhang, Xiaoying Wang, Jing Fang

Critical limb ischemia (CLI) represents the most severe clinical manifestation of peripheral arterial disease (PAD). It has been proved that l lower extremity arterial stenosis and collateral circulation compensatory ability after occlusion play an important role on CLI. This study proposed a strategy for assessment of lower extremity arterial stenosis and collateral circulation compensatory ability by the noninvasive vessel-encoded arterial spin labeling (VEASL) to quantitatively assess perfusion territory of lower extremity arterial. The lower limb perfusion territory image and the angiosome map were obtained in this study, indicating the potential of VEASL for CLI assessment.

Brian Noehren, Richard Lawless, Peter Hardy, Anders Andersen, Moriel Vandsburger

Anterior Cruciate Ligament Injuries are associated with long term loss of quadriceps muscle strength. Accumulation of greater collagen in the extracellular matrix around muscle fibers could limit recovery. T1p applied to the quadriceps muscle could identify patients at risk for not having a good recovery because of collagen deposition. T1p imagining of the injured and non injured quadriceps of 6 subjects was performed. We found significantly higher T1p times in the injured limb as well as a significant association to greater muscle weakness. These results show the potential application of T1p to identify individuals with muscle dysfunction.

Benjamin Marty, Bertrand Coppa, Pierre-Yves Baudin, Pierre Carlier

The development of quantitative NMR outcome measures in order to monitor natural history of neuromuscular disorders or therapeutic interventions is crucial. Global muscle T1 values is strongly affected in chronic disease when healthy muscle is replaced by fat and this parameter can be used for diagnostic purposes. Nevertheless, very little is known about the effects of tissue water compartmentation and distribution on muscle T1 values. Here, we investigated the variations of skeletal muscle T1 values under various physiological conditions using a fast T1 mapping sequence and evaluated the potential of this biomarker in the context of disease monitoring.

Jin Qu, Xinwei Lei, Ying Zhan, Huixia Li, Yingying An, Zhizheng Zhuo

The purpose of this study was to evaluate fatty infiltration of supraspinatus quantitatively using fat fraction measurements and investigate the relationship between fatty infiltration, muscle atrophy and tendon tear severity. Quantitative assessment of fatty infiltration was performed using 3T MRI with a mDIXON-Quant technique in 85 patients. The degree of fatty infiltration and muscle atrophy signi?cantly increase with the extent of rotator cuff tear. The tendon tear severity correlated with fatty infiltration and muscle atrophy, and muscle atrophy correlated with fatty infiltration. mDIXON-Quant can be a reliable and accurate tool to quantify fatty degeneration of the rotator cuff muscles.

Melissa Hooijmans, Nathalie Doorenweerd, Jedrzej Burakiewicz, Celine Baligand, Jan Verschuuren, Andrew Webb, Erik Niks, Hermien Kan

Quantitative MR of muscle is increasingly important as potential outcome measure for therapy development in DMD. Since therapy is aimed at preserving or improving muscle tissue, an early marker that reflects muscle state with a suitable dynamic range is essential. Unfortunately, water T2 and %fat do not meet this criteria. Therefore, we aimed to assess whether phosphodiester (PDE)-levels detected by 31P MRS could fill this gap. We have shown a two-fold increase in PDE-levels compared to controls and its detection prior to structural changes which confirm the potential of PDE as an early marker for disease activity in DMD patients.

David Reiter, Christopher Bergeron, Richard Spencer, Luigi Ferrucci, Itamar Ronen

Micro- and ultrastructural properties of skeletal muscle have a direct impact on function and modulate the diffusion of both water and metabolites.  Anomalous diffusion models can be used to characterize non-Gaussian diffusion and specifically subdiffusive dynamics, which are expected to reflect ultra-structural tissue properties.  Here, we present fits of the single-parameter Mittag-Leffler diffusion model to diffusion weighted spectroscopy data, showing subdiffusive motions of skeletal muscle water and metabolites.

Esther Yang, Amy Kirkham, Richard Thompson

The magnetic field shift within cylindrical blood vessels can be used to estimate venous oxygen saturation, based on the magnetic susceptibility of deoxyhemoglobin. However, conduit veins in the periphery are often surrounded by fat, which has a larger magnetic susceptibility than water and the venous blood pool. It is shown that the magnetic susceptibility effects of fat can confound estimation of venous oxygen saturation. A new method to correct for these effects is described with application for plantar flexion exercise, for the measurement of muscle oxygen extraction, blood flow and calculation of oxygen consumption (VO₂).

Xiaodong Zhang, Yinxia Zhao, Yingjie Mei, Shaoyong Hu

The intervertebral disc without blood supply obtained nutrient substance diffusing from the microcirculation under vertebral endplates. Some studies showed the fat deposition of bone marrow may pressure vessels and blood sinus, which could affect the microcirculation. So the fatty content of bone marrow under vertebral endplates can reflect the degeneration of the vertebral. However, the correlation of fatty content of bone marrow with lumbar intervertebral disc degeneration is not clear. The purpose of our study was to analyze the correlation between bone marrow fatty fraction under vertebral endplates with Pfirrmann Grades and T2* value of lumbar intervertebral disc.

Raphaële charest-morin, Honglin Zhang, Michael Bond, Amy Phillips, Shannon Patterson, David Wilson, John Street

The planning of spine surgery for degenerative lumbar spondylolisthesis (DLS) is currently based on supine MR images while patients experience symptoms in the upright posture.  This study employed an upright Open MRI to determine whether the MRI-based measurements of the spinal and neural elements used in planning surgery are different in the symptomatic, upright posture than in the supine posture.  We found upright MRI scanning detected dynamic morphometric differences in a number of clinically important radiographic parameters in patients with DLS.  Upright MRI may help in planning minimally invasive surgeries for DLS.

L. Tugan Muftuler, Volkan Arpinar, Ali Ersoz

This study investigated changes in perfusion and diffusion in the cartilaginous endplates and subchondral bones around the degenerating discs. It has been suggested that such abnormalities might indicate inflammatory changes that might lead to chronic low back pain. A high spatial and temporal resolution DCE-MRI technique was implemented and tested on a group of volunteers. Pharmacokinetic model was used to quantify the changes in the regions of interest. Results demonstrated significant changes in contrast agent uptake and washout in the cartilaginous and bony endplate regions as the adjacent disc degenerated.

Munenobu Nogami, Shinsuke Shimoyama, Yuichi Wakabayashi, Utaru Tanaka, Yoshiaki Watanabe, Akihito Ohnishi, Tatsuya Nishii, Yoshiko Ueno, Atsushi Kono, Kazuhiro Kubo, Satoru Takahashi, Kazuro Sugimura

Hybrid PET/MRI scanner is an emerging modality and utilized not only for oncological or neurological purposes but also for assessment of musculoskeletal disease.  Simultaneous acquisition of PET and MRI enables precise anatomical localization of PET tracers and further understanding of mechanism of the tracer uptake by using MRI information.  Our hypothesis was that PET/MRI can reveal the pathophysiological mechanism of facet joint osteoarthritis by the simultaneous whole body imaging.  The results showed MRI features on PET/MR significantly correlated with FDG uptake in the facet joint osteoarthritis and may be superior to CT based evaluation.

Shinpei Yamaguchi, Takatoshi Aoki, Koichi Nakagami, Masami Fujii, Yoshiko Hayashida, Yosuke Okada, Yoshiya Tanaka, Yukunori Korogi

Although bone mineral density (BMD) by dual X-ray absorptiometry (DXA) has been used to predict bone strength, diabetes mellitus (DM) patients have an elevated fracture risk despite normal BMD. We evaluated the availability of the fat fraction (FF) using IDEAL-IQ for vertebral strength prediction in DM patients. The correlation between the failure load by CT-based finite-element method and the BMD with age and the FF using IDEAL-IQ was significantly higher than that between the failure load and the BMD alone (p<.001). FF using IDEAL-IQ in combination with BMD measurements can potentially be used in predicting bone strength in DM patients.

Ho-Joon Lee, Suchandrima Banerjee, Dong Eun Kim, Sung-Min Gho, Seung-Koo Lee

Application of the volumetric fast spin echo (FSE) imaging in MRI is increasing, due to innate capability for multi-planar reconstruction, and potentials for a simplified workflow.  However application to the cervical and thoracic area may be challenging because ghosting/phase encoded motion artifacts from swallowing, respiration and pulsations are frequent and severe in these regions, leading to image degradation. 3D FSE with outer volume suppression is a robust method for imaging the cervical spine, which provides improved image quality at a decreased scan time.

Miyuki Takasu, Yuji Akiyama, Kazushi Yokomachi, Yoko Kaichi, Chihiro Tani, Koichi Oshio, Kazuo Awai

We compared the potential of various diffusion parameters obtained from Gaussian and non-Gaussian diffusion models in differentiating focal lesions of malignant spinal tumors. Mean signal intensity was calculated by placing ROIs within focal lesions for 9 b-values in each subject. ADC, frac<1, frac>3, and PG(D) differed significantly between focal lesions of myeloma and LCA. Frac>3 and PG(D) was significantly different between focal lesions of myeloma and MMK. Non-Gaussian diffusion parameters may provide additional information and improve the differentiation of malignant focal lesions compared with conventional diffusion parameters, which would be helpful in improving therapy strategies.

Daisuke Nakashima, Nobuyuki Fujita, Junichi Hata, Takeo Nagura, Kanehiro Fujiyoshi, Hideyuki Okano, Masahiro Jinzaki, Morio Matsumoto, Masaya Nakamura

 Pfirrmann classification on T2WI has been the qualitative grading of intervertebral disc (IVD) degeneration which is difficult to classify subtle changes of degeneration. A quantitative and more sensitive classification system has been sought.  

 In this research, probability at zero displacement obtained from Q-space imaging (QSI) which is a quantitative diffusion-weighted MRI procedure made it possible to observe the effect of the regenerative antioxidant drug: N-Acetyl Cystaine on IVD degeneration which could not be observed by using T2 mapping.

 Probability at zero displacement obtained from QSI has the possibility to be a novel biomarker of IVD degeneration.

Xiulan Zhang, Yongmin Bi, Wanshi Zhang, Lizhi Xie

Degenerative disc disease is an occupational disease of the military pilots, which seriously influcenes  their health and normal training. Early disc degeneration begins with changes in biochemical compositions which is mainly characterized by proteoglycan lose and cannot be detected on conventional MRI imaging^[1-2]. T1rho is a quantitative imaging technique to reflect changes in the extracellular matrix, such as modifications in the intervertebral disc PG content^[3]. In this study,Bivariate correlation analysis was performed to compare T1rho values to the degenerative grade, disc space level, age and flight time of the pilots. T1rho values of Lumbar intervertebral discs in pilots demonstrated significantly negative correlations with degenerative grade, age and flight time, except for disk space levels. T1rho can be potentially used as a valid clinical method in the quantitative diagnosis of early intervertebral disc degeneration in asymptomatic Pilots. 
 

Dong Xing, Yunfei Zha, Fang Liu, Liang Li, Feifei Zeng, Yuan Lin, Wei Gong, Lei Hu, Jiao Wang, Bing Wu, Hui Lin

IVIM (Intravoxel incoherent motion) provides perfusion quantification without the need for intravenous contrast injection, and has been used to the spinal bone marrow lesions^1,2. However, diffusion weighted imaging is prone to image deformation, especially with a large FOV. Hence the quantitative measurement of IVIM in spinal bone morrow may be affected. Reduced FOV DWI is known to reduce the level of image distortion, and the purpose of this study is to compare the IVIM parameters obtained using full FOV or reduced FOV imaging.

Hitoshi Tadenuma, Kayoko Abe, Masami Yoneyama, Yasuhiro Goto, Makoto Suzuki, Mamoru Takeyama, Shuji Sakai

The role of MRI in the diagnosis of Lumbrosacral plexopathy is in depiction of the anatomical detail of pelvic nerves. This study attempted the improvement of the pelvic nervous depiction using HIRE-SHINKEI. This applies HIRE technique, and requires both SHINKEI and additional 3D heavily T2W scan to subtract the data. HIRE-SHINKEI can improve the depiction of nerves by subtracting signals of the background. This new technique has great potential to help the diagnosis for the peripheral nerve disorders of the lumbosacral region. 

Ning Lang, Huishu Yuan, Min-Ying Su

A retrospective DCE-MRI of 23 patients with confirmed myeloma and 13 patients with spinal lymphoma were found. A group of 76 patients with different metastatic cancers in the spine was used as a comparison group. Three heuristic parameters: the steepest wash-in enhancement ratio, the initial area under the curve (IUAC) enhancement ratio, and the wash-out slope were measured. In the ROC analysis based on the wash-out slope, myeloma can be differentiated from lymphoma with AUC=0.913, and from mets with AUC=0.828. The wash-out slope can also differentiate lung mets from breast mets with AUC=0.812, and from thyroid mets with AUC=0.891.

Stephen Fisher, Alfonso Rodriguez, Jing Wang, Michael Folkert, Avneesh Chhabra

Texture analysis has yet to be exploited in musculoskeletal tumors. In this study we aimed to create a novel predictive model based on features of benign and malignant musculoskeletal masses and test this model against existing methods used in other parts of the body. Our workflow shows promise for creating accurate classifiers of benign and aggressive tumors based on T2-weighted MRI images.

Marius Horger, Sebastian Werner, Wolfgang Thaiss, Christopher Kloth

Imaging diagnosis and therapy monitoring of multiple myeloma (MM) is challenging due to the combined bone and bone marrow involvement and at the same time often imperative due to possible failure of hematological markers (e.g. non-secretory myeloma). MRI is the most powerful MM-imaging technique for visualization of medullar involvement whereas CT optimally detects myeloma bone-disease (BMD). A new CT post-processing software (bone subtraction-BS) is generating subtraction (difference) maps of baseline and follow-up non-enhanced CT exams highlighting the course of BMD. Hence, the purpose of this study was to assess strengths and limitations of these two imaging modalities for longitudinal disease monitoring.  

Yitong Bian, Guohong Jin, Yanliang Wang, Gang Niu, Jian Yang

Precise differential and qualitative diagnoses for extremities soft tissue tumors(STTs) are of vital importance. Dynamic susceptibility contrast perfusion MRI(DSC-MRI) enables assessment of overall tumor vascularity, allowing indirect evaluation of the biological aggressiveness of tumors. Therefore, this study aims to discuss the feasibility of DSC-MRI to preliminarily assess in the differentiation between benign and malignant extremities STTs. Our results showed that DSC-MRI might be a non-invasive imaging technique that can play a role in identifying malignant and benign STTs in limbs and provide reliably pathological or physiological information for clinic.

Ying Li, Cuiping Ren, Jingliang Cheng, Zhizheng Zhuo

This work investigated and evaluated the role of texture analysis based on intra-voxel incoherent motion(IVIM) MR imaging to characterize the bone tumors,and furtherly evaluate the ability of the texture parameters to differentiate benign and malignant bone tumors by using a couple of classifiers, which might be helpful for clinical diagnosis and studies. The texture parameters have the ability to character the bone tumor and the naïvebayes classifier showed the best performance in the differentiation of benign and malignant bone tumors.

Ying Li, Cuiping Ren, Jingliang Cheng, Zhizheng Zhuo

This work investigated and evaluated the role of dynamic contrast enhanced magnetic resonance imaging(DCE-MRI) in characterizing the soft tissue tumors, and furtherly evaluate the ability of permeability parameters to differentiate benign and malignant tumors by using random tree and artificial neural network classifiers, which might be helpful for clinical diagnosis and studies.

Ying Li, Cuiping Ren, Jingliang Cheng, Zhizheng Zhuo

This work investigated and evaluated the role of magnetic resonance (MR) diffusion kurtosis imaging(DKI) in characterizing the musculoskeletal tumors, and furtherly evaluate the ability of DKI parameters to differentiate benign and malignant tumors by using a classifier based on random forest method, which might be helpful for clinical diagnosis and studies.

Ying Li, Cuiping Ren, Jingliang Cheng, Zhizheng Zhuo

This work investigated and evaluated the role of intra-voxel incoherent motion(IVIM) MR imaging in characterizing the bone tumors, and furtherly evaluate the ability of IVIM parameters to differentiate benign and malignant tumors by using a support vector machine (SVM) classifier, which might be helpful for clinical diagnosis and studies.

Hyun Su Kim, Young Cheol Yoon

The presence of the epidermal growth factor receptor (EGFR) gene mutation is associated with a high rate of distant metastasis and poor prognosis in patients with non-small cell lung cancer (NSCLC). EGFR signaling acts as mediator of bone metastasis by increasing tumor cell proliferation and promotes synthesis and secretion of numerous angiogenic growth factors. We propose that metastatic bone lesions with and without the EGFR mutation in primary NSCLC have different perfusion profiles and dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) parameters can reveal the differences. 

Richard Kijowski, Benjamin Beduhn, Michael Fazio, Fang Liu

This study was performed to investigate changes in meniscus T2 relaxation time at various stages of knee joint degeneration. T2 mapping was performed on the knees of 121 patients with meniscus tears.  T2 of the torn and untorn portions of the medial and lateral meniscus were measured.  The severity of radiographic osteoarthritis was assessed using the Kellgren-Lawrence (KL) grading scale.  There was a significant difference (p<0.001) in meniscus T2 between KL0, KL1, and KL2 subjects in both the torn and untorn portions of the meniscus with KL2 subjects having the highest T2 and KL0 subjects having the lowest T2.  

Marianne Black, Garry Gold, Marc Levenston, Brian Hargreaves

The menisci of the knee are important for distributing load at the knee joint, and meniscal damage has been shown to precede cartilage degeneration in the knee. We examined radial and circumferential meniscal variation in T2, T2* and T1rho relaxation times in osteoarthritic menisci. Menisci were divided into 3 circumferential regions (anterior, body, and posterior) and then further into 3 radial regions (inner, middle, and outer). Significant differences were found between circumferential and radial regions for T2, but only between circumferential regions for T2* and T1rho. Changes in meniscal regional variations could be important in tracking osteoarthritis disease progress.

Susanne Eijgenraam, Frans Bovendeert , Yvonne Bastiaansen , Duncan Meuffels, Jamal Guenoun , Stefan Klein, Max Reijman, Edwin Oei

To validate meniscal T2-mapping, which is suggested to detect early meniscal degeneration, T2 relaxation times of ten menisci (five traumatically torn and five degenerative menisci from 10 patients) were compared to histopathology as the gold standard to assess meniscal degeneration. T2  relaxation times were found to correlate well with histopathological degree of degeneration in meniscal tissue (rs = 0.64, P = 0.001). Degenerative meniscal tissue was found to exhibit significantly higher T2 relaxation times compared to non-degenerated meniscal tissue (22.7±3.0 ms and 18.2 ±5.1 ms (P = 0.02) respectively). Therefore, T2-mapping is a promising quantitative imaging biomarker for meniscal degeneration.