MSK - General

Monday 1 June 2015

Jose D Sergio Almeida¹, Flora Gröning², and Jiabao He^1
1Aberdeen Biomedical Imaging Centre, University of Aberdeen, Aberdeen, Scotland, United Kingdom, ²Anatomy and Musculoskeletal Research Programme, University of Aberdeen, Aberdeen, Scotland, United Kingdom

Masticatory system is complex, attracting significant interest in understanding its function. However, current literature evidence has limited consistency, often attributed to multifactorial nature of masticatory dysfunction. It is therefore valuable to assess the reproducibility of bone and muscle morphological measurements and muscle DTI parameters, where signal level and spatial accuracy are competing factors. We found that bone morphological parameters are highly reproducible, while muscle volume reproducibility depends on the volume magnitude. For DTI parameters, only masseter measurements are reproducible. Our finding indicates that clinical studies of masticatory system should carefully consider power calculation to ensure the validity of the conclusion.

Michael Carl¹, Jiang Du², and Graeme M Bydder^2
1GE Healthcare, San Diego, CA, United States, ²UCSD, CA, United States

Magnetization inversion is an important tool in UTE MRI to generate short T2 contrast and selectively eliminate certain long-T2 signals in the image, such as fat or muscle. Volunteer experiments were performed to demonstrate the ability of IR prepared UTE to directly image short T2 tissues such as cortical bone within clinical scantimes.

Faezeh Fallah^1,2, Christian Wuerslin¹, Fritz Schick¹, and Bin Yang^2
1Section on Experimental Radiology, University Clinic of Tübingen, Tübingen, Baden-Wuerttemberg, Germany, ²Institute of Signal Processing and System Theory, University of Stuttgart, Stuttgart, Baden-Wuerttemberg, Germany

To provide an optimal basis for automatic tissue segmentation and enhancement of visual inspection of the magnitude images, we propose an anatomic-supported, reliable and fast algorithm for mitigation of intensity inhomogeneities resulting from modern array coils and dielectric effects. The skeletal musculature consisting of different muscle groups separated by fascia is considered as reference. This method is a generalization of the previous method, by making it applicable to different image orientations, T1-weighted and fat-suppressed images. Performance in terms of the mean coefficient of the variance of the muscle tissues is compared with local entropy minimization with bi-cubic spline model (LEMS).

Taro Sakashita¹, Tamotsu Kamishima², Hiroyuki Sugimori³, Meiki Tou⁴, Atsushi Noguchi⁵, Michihito Kawano⁶, and Tatsuya Atsumi^5
1Graduate School of Health Sciences, Hokkaido University, Sapporo, Hokkaido, Japan, ²Faculty of Health Sciences, Hokkaido University, Hokkaido, Japan, ³Department of Radiology, Hokkaido University Hospital, Hokkaido, Japan, ⁴Graduate School of Health Sciences, Hokkaido University, Hokkaido, Japan, ⁵Internal Medicine 2, Hokkaido University Hospital, Hokkaido, Japan, ⁶Obihiro-Kosei General Hospital, Hokkaido, Japan

We hypothesized that pixel by pixel, time-intensity curve (TIC) shape analysis can accurately quantify the pannus of rheumatoid patents. Area of enhancing pannus (AEP) measurement via segmentation using thresholding (AEP_THRES) and via pixel by pixel TIC analysis (AEP_TIC) was compared by setting the volume of enhancing pannus (VEP) by manual contouring (AEP_MANUAL) as gold standard to evaluate accuracy of VEP quantification. Correlation coefficient between AEP_TIC and AEP_MANUAL was evaluated as better than that of AEP_THRES and AEP_MANUAL in the wrist region. Pixel by pixel TIC analysis may be an alternative to manual contouring for pannus quantification in the hand.

Junghyo Kim¹, Takashi Nishii², Hidetoshi Hamada¹, Masaki Takao¹, Takashi Sakai¹, Tetsuya Tomita³, Kazuma Futai³, Hisashi Tanaka⁴, Hideki Yoshikawa¹, and Nobuhiko Sugano^1
1Department of Orthopaedic Surgery, Osaka University Graduate School of Medicine, Suita, Osaka, Japan, ²Department of Orthopaedic Medical Engineering, Osaka University Graduate School of Medicine, Osaka, Japan, ³Departments of Orthopedic Biomaterial Science, Osaka University Graduate School of Medicine, Suita, Osaka, Japan, ⁴Department of Radiology, Osaka University Graduate School of Medicine, Suita, Osaka, Japan

The aim of the current study was to assess volume of synovial membrane and synovial fluid on non-enhanced T2 mapping and examine associations of synovial inflammation activity with clinical symptom and structural disorders of the articular cartilage and meniscus. The volumes of synovial membrane and fluid by T2-mapping were calculated similarly to the volumes by contrast-enhanced MR sequences. There is high correlation between the volume of synovial membrane and knee pain score.

Yeji Han¹, Yeon Chul Ryu², and Jun-Young Chung^1
1Department of Biomedical Engineering, Gachon University, Incheon, Incheon, Korea, ²Neuroscience Research Institute, Gachon University, Incheon, Incheon, Korea

In musculoskeletal MR imaging, fat suppression is an important factor that contributes to the visibility of bone-marrow lesions and soft-tissue masses, improves the contrast-to-noise ratio in magnetic resonance (MR) arthrography, and prevents chemical shift artifacts. In this study, a technique based on two off-resonance RF pulses is proposed as a fat suppression method that is less dependent on the field homogeneity.

HIDETOSHI HAMADA¹, Takashi Nishii¹, Kim Junghyo¹, Hisashi Tanaka², and Nobuhiko Sugano^1
1Departments of Orthopedic Surgery, Osaka University Graduate School of Medicine, Suita, Osaka, Japan, ²Department of Diagnostic and Interventional Radiology, Osaka University Graduate School of Medicine, Suita, Osaka, Japan

Radial MRI with T2 mapping and T2*- and T2-weighted sequences was useful in non-invasive reliable assessment of cartilage and labral lesions over the whole acetabular area.

Olgica Zaric¹, Pavol Szomolanyi¹, Vladimir Mlynarik¹, Vladimir Juras¹, and Siegfried Trattnig^1
1High Field MR Center, Department of Biomedical Imaging and Image-guided Therapy, Medical University of Vienna, Vienna, Austria

Recent studies has shown that removal of the entire meniscus can lead to the development of osteoarthritis in a high proportion of cases in a long run. This study used 3 Tesla gagCEST MRI for early postoperative quantitative evaluation of biochemical changes in articular cartilage adjacent to operated meniscus after PMA. We observed lower gagCEST values in cartilage adjacent to the operated meniscus than in the healthy cartilage within the same subject. This loss in GAG content could be biomarker of early cartilage degeneration. gagCEST at 3 Tesla has great potential in the investigation of early signs of osteoarthritis.

Takako Aoki¹, Hiroshi Kawaguchi², Takahiro Watanabe³, Yomei Tachibana⁴, Hiroshi Imai⁵, Benjamin Schmitt⁶, and Mamoru Niitsu^4
1Radiology, Saitama medical university hospital, Moroyama-machi, Iruma-gun, Japan, ²National Institute of Radiological Sciences, Japan, ³Saitama medical university hospital, Moroyama-machi, Iruma-gun, Japan, ⁴Saitama medical university, Japan, ⁵Siemens Japan K.K., Japan, ⁶Healthcare Sector, Siemens Ltd., Australia

Investigating the relevance of gag-CEST mapping to clinical arthroscopic findings.

Kevin D'Aquilla¹, Miltiadis Zgonis², J. Bruce Kneeland³, Hari Hariharan¹, and Ravinder Reddy^1
1Center for Magnetic Resonance and Optical Imaging, Department of Radiology, University of Pennsylvania, Philadelphia, PA, United States, ²Department of Orthopedic Surgery, Hospital of the University of Pennsylvania, Philadelphia, PA, United States, ³Department of Radiology, Hospital of the University of Pennsylvania, Philadelphia, PA, United States

T1ρ MRI is an emerging technique that is especially valuable as a tool for assessing cartilage health. The causes of patellofemoral pain, a common ailment in young adults, often include alterations to the articular cartilage of the knee that cannot be visualized by traditional MRI methods. This study assesses by T1ρ MRI the patellar and femoral cartilage in human patients diagnosed with patellofemoral overload. Findings include T1ρ increases on the lateral facet of both the femoral and patellar cartilage in subjects with patellofemoral pain and patellofemoral overload.

Hon J. Yu^1,2, Taiki Nozaki¹, Yasuhito Kaneko¹, Kayleigh Kaneshiro¹, Ran Schwarzkopf³, and Hiroshi Yoshioka^1
1Radiological Sciences, University of California, Irvine, CA, United States, ²Tu & Yuen Center for Functional Onco-Imaging, University of California, Irvine, CA, United States, ³Orthopaedic Surgery, University of California, Irvine, CA, United States

Geometrical-attribute based comparison of inter-operator manual segmentation is demonstrated using MRI of articular cartilage. When combined with Bland-Altman analysis rather than more commonly used regression approach, such inter-operator assessment could provide a more insightful comparison that is not biased by the underlying segmentation-based quantity (e.g., T2 or T1ĉvalue) and can be also extended to segmentation assessment based on semi-/automatic schemes.

Soorena Azam Zanganeh¹, Chantal Pauli², Christine B Chung³, Eric Chang³, Graeme M Bydder³, Darryl DLima², and Jiang Du^3
1Radiology, University of California, San Diego, San Diego, CA, United States, ²Department of Molecular and Experimental Medicine, the Scripps Research Institute, San Diego, CA, United States, ³Radiology, University of California, San Diego, San Diego, CA, United Kingdom

Articular cartilage with its special structure has been studied for different layers including superficial zone which fibers are parallel to surface,transitional zone with random fibers or curved fibers and deep zone fibers are perpendicular to the surface . structures which are good explanation of magic angle effect when fibers are oriented at 54 degree. As an importance of vertical striation with different magic angel effect we investigate the fiber structure of articular cartilage using polarized light microscopy and high resolution magnetic resonance imaging plus histology.for histology we used the Safranine O-Green staining with PLM of medial and lateral tibial plateau which are the surfaces are covered whit menisci.

Joanna Yuen¹, Jachin Hung², Vanessa Wiggermann^1,2, Robert McCormack³, Agnes d'Entremont^4,5, and Alexander Rauscher^1,2
1UBC MRI Research Centre, Vancouver, British Columbia, Canada, ²Department of Physics and Astronomy, The University of British Columbia, Vancouver, British Columbia, Canada,³Department of Orthopaedics, The University of British Columbia, Vancouver, British Columbia, Canada, ⁴Department of Mechanical Engineering, The University of British Columbia, Vancouver, British Columbia, Canada, ⁵Centre for Hip Health and Mobility, Vancouver, British Columbia, Canada

The frequency of susceptibility-weighted MR signal has proven to be highly sensitive to changes in tissue microstructure, which may reflect pathologic changes. We explored the potential of a multi-echo SWI to image articular cartilage damage. Four patients were scanned on a 3T scanner. MR signal magnitude, frequency, and T2* maps were generated and compared to arthroscopic video. Grade I, II, and III changes were detected in arthroscopy, average magnitude, and T2* maps, while Grade II and III changes were observable on MR frequency maps. This study demonstrates the use of different SW contrasts to visualize OA-related changes in knee cartilage.

Jae-Seung Lee¹, Ding Xia¹, and Ravinder R. Regatte^1
1Department of Radiology, New York University, New York, NY, United States

In the filed of sodium MRI, IR has been a popular method to discriminate the sodium content between different environments. While adiabatic pulses, such as WURST pulses, are usually used for the better inversion of the magnetization vector under B₀ and B₁ inhomogeneities, RF shapes robust against the field inhomogeneities can be obtained through numerical optimization based on optimal control theory. In this work, we designed optimal RF shapes to improve the performance of sodium IR MRI of the knee joint, in terms of fluid suppression, contrast between cartilage and artery, and SAR.

Wolfgang Marik¹, Stefan Nemec², Stefan Zbyn³, Martin Zalaudek³, Bernhard Ludvik⁴, Manuela Karner³, and Siegfried Trattnig^3
1Department of Biomedical Imaging and Image-guided Therapy, Medical University of Vienna, Vienna, Vienna, Austria, ²Department of Biomedical Imaging and Image-guided Therapy, Medical University of Vienna, Vienna, Austria, ³MR Centre of Excellence, Department of Biomedical Imaging and Image-guided Therapy, Medical University of Vienna, Vienna, Austria,⁴Clinic for Internal Medicine III, Department of Endocrinology and Metabolism, Medical University of Vienna, Vienna, Austria

Purpose: Investigate biochemical alterations of tendons and cartilage caused by DM Type 1 using quantitative in vivo sodium MR imaging at 7 Tesla. Methods: Eight patients with DM Type 1 and nine healthy volunteers were examined on a 7 Tesla MR. All participants underwent morphological and sodium image analysis. Region of interest analysis was performed manually for the femoral cartilage and patella tendon. For intra- and interreader agreement two different readers solitary evaluated the same image data sets. Results: Morphological imaging revealed no difference between groups. Sodium MR imaging revealed stasticaly significant altered NMSI values for patients in cartilage an tendons (p=. 008; p= .025). Conclusion: Statistically significant difference in NMSI values was seen in patients compared with a healthy control group.

Ji hyun Lee¹, Farid Badar², and Yang Xia^3,4
1Oakland Univ, Rochester, Michigan, United States, ²Oakland Univ, Michigan, United States, ³Physics, Oakland University, Rochester, Michigan, United States, ⁴Center for Biomedical Research, Oakland University, Michigan, United States

This study quantified the topographical and zonal changes of T1 in healthy and osteoarthritic tibial cartilage in canines. T1 of cartilage when soaked in gadolinium showed an increasing trend from the surface to deep cartilage. The zonal T1 values from the meniscus-covered area were significantly higher than those from the uncovered area for most sub-tissue zones (except the deepest tissue and bulk). The average T1 decreased with OA advance and the cartilage thickness increased at early osteoarthritic lesion. This study could help to design more effective protocols to detect the early lesions in the clinics.

Luning Wang¹, Mikko J Nissi², Ferenc Toth³, Cathy Carlson³, and Jutta Ellermann^1
1Center for Magnetic Resonance Research, University of Minnesota, Twin Cities, Minneapolis, MN, United States, ²Medical Research Center Oulu, Oulu University Hospital and University of Oulu, Finland, ³University of Minnesota, Twin Cities, Minneapolis, MN, United States

In this study, established and novel MR relaxometry methods are utilized in the developing skeleton to study cartilage maturation. Quantitative Relaxation time mapping, T1, T2, contineous wave (CW) T1�, adiabatic T1�, and TRAFF, revealed consistently higher relaxation times in articular compared to epiphyseal cartilage with peak relaxation times occurring in both at about 3 weeks of age. Multiparametric MR relaxometry serves as a valuable noninvasive tool for monitoring changes in cartilage during normal maturation in goats and may be applied in the future to study developmental abnormalities in both animals and human beings.

Victor Casula^1,2, Joonas Autio³, Mikko J. Nissi^3,4, Michaeli Shalom⁴, Silvia Mangia⁴, Edward Auerbach⁴, Jutta Ellermann⁴, Eveliina Lammentausta³, and Miika T. Nieminen^1,3
1Department of Radiology, University of Oulu, Oulu, Oulu, Finland, ²Medical Research Center Oulu, Oulu University Hospital and University of Oulu, Oulu, Finland, ³Department of Diagnostic Radiology, Oulu University Hospital, Oulu, Finland, ⁴Center for Magnetic Resonance Research, Department of Radiology, University of Minnesota, Minneapolis, United States

Adiabatic T₁ and T₂ sequences were tested on a 3 T clinical system for mapping of articular cartilage. Phantom experiments with hyperbolic secant pulses (HS4) revealed excellent accuracy of the sequences and strong dependencies of R₁ and R₂ on agarose and chondroitin sulfate concentration, which are relevant for cartilage. The findings demonstrate that adiabatic T₁ and adiabatic T₂ techniques are promising tools for in vivo cartilage imaging at 3T.

Lasse P. Räsänen¹, Stefan Zbyn², Miika T. Nieminen^3,4, Eveliina Lammentausta³, Xeli Deligianni^5,6, Oliver Bieri⁵, Siegfried Trattnig², and Rami Korhonen^1
1Department of Applied Physics, University of Eastern Finland, Kuopio, Finland, ²MR Centre-High Field MR, Department of Biomedical Imaging and Image-Guided Therapy, Medical University of Vienna, Vienna, Austria, ³Department of Diagnostic Radiology, Oulu University Hospital, Oulu, Finland, ⁴Department of Radiology, University of Oulu, Oulu, Finland, ⁵Division of Radiological Physics – Department of Radiology, University of Basel Hospital, Basel, Switzerland, ⁶Merian Iselin Klinik, Basel, Switzerland

The importance of the biexponential decay of the transverse relaxation of sodium (²³Na) and the signal attenuation due to partial volume effect (PVE) were investigated, while determining²³Na concentration and FCD of the tibial and femoral cartilage tissues with MRI. The use of biexponential signal correction together with PVE increased the ²³Na concentrations up to +179%, thus also enabling the quantification of FCD of cartilage. The results suggest that biexponential signal decay and PVE can be notable even at 7T and relatively small resolution and should be considered when quantifying ²³Na content and FCD from ²³Na-MRI.

Mikko Johannes Nissi^1,2, Victor Casula^1,2, Eveliina Lammentausta^2,3, Shalom Michaeli⁴, Silvia Mangia⁴, Edward Auerbach⁴, Jutta Ellermann⁴, and Miika T Nieminen^1,3
1Department of Radiology, Institute of Diagnostics, University of Oulu, Oulu, Finland, ²Medical Research Center Oulu, Oulu University Hospital and University of Oulu, Oulu, Finland,³Department of Radiology, Oulu University Hospital, Oulu, Finland, ⁴CMRR, Department of Radiology, University of Minnesota, Minneapolis, MN, United States

Magic angle effect is a major confounding factor in both quantitative and qualitative assessment of articular cartilage, as well as of other tissues. Recently, reduced magic angle dependence was demonstrated for adiabatic T₁ relaxation time in articular cartilage. In this work, adiabatic T₁ and T₂ relaxation time constants of human knee articular cartilage were measured in vivo at 3 T. Adiabatic T₁ relaxation time maps demonstrated reduced magic angle effect in cartilage regions at susceptible angles as compared to T₂ relaxation time. Adiabatic T₁ technique provides a promising alternative to T₂ for the assessment of articular cartilage.

Fan Jia¹, Rui Zhang², Hongyang Yuan², Jue Zhang^1,2, Diange Zhou^1,3, Xiaoying Wang^1,4, and Jing Fang^1,2
1Academy for Advanced Interdisciplinary Studies, Peking University, Beijing, Beijing, China, ²College of Engineering, Peking University, Beijing, Beijing, China, ³Arthritis Clinic and Research Center, Peking University People' s Hospital, Beijing, Beijing, China, ⁴Dept. of Radiology, Peking University First Hospital, Beijing, Beijing, China

In this study, a multi-purpose flexible antenna, which consists of a flex cable, a tuning/matching circuit and a transmission line, was developed for musculoskeletal MR imaging. The imaging results of shoulder, hand and wrist have shown the high SNR and satisfied magnetic field homogeneity of the flexible antenna while the experimental results of elbow, ankle and knee under different flexion angles have also demonstrated the high flexibility, satisfied comfort and large FOV of the flexible antenna. In the near future, it is believed that the flexible antenna can be applied for real-time imaging of joint movement under dynamic situations.

Martin Krämer¹, Karl-Heinz Herrmann¹, Heide Boeth², Christoph von Tycowicz³, Christian König², Stefan Zachow³, Rainald M Ehrig³, Hans-Christian Hege³, Georg N Duda², and Jürgen R Reichenbach^1
1Medical Physics Group, Institute of Diagnostic and Interventional Radiology, Jena University Hospital - Friedrich Schiller University Jena, Jena, Germany, ²Julius Wolff Institute and Center for Musculoskeletal Surgery, Charité – Universitätsmedizin Berlin, Berlin, Germany, ³Zuse Institute Berlin, Berlin, Germany

To acquire dynamic movements of the whole knee with isotropic resolution a 3D radial center-out acquisition scheme is combined with a low cost experimental measurement setup to perform single passive knee flexion. With a spatial resolution of (1.25×1.25×1.25) mm³, the acquired 4D dynamic data sets are well suited for highly flexible subsequent image analysis including reconstruction of arbitrarily oriented or curved slices. In this work, we describe the measurement setup and imaging sequence and show the first basic measurement and reconstruction results.

Adil Bashir¹, Robert Gropler¹, and Jie Zheng^1
1Mallinckrodt Institute of Radiology, Washington University, St. Louis, MO, United States

Chronic disease such as heart failure, diabetes, peripheral artery disease etc. negatively impact muscle blood flow (BF) and perfusion and thereby lead to metabolic disorders, diminished exercise capacity and tissue loss. In this work, we have developed a time-resolved method to measure BF, perfusion and oxygen (O2) consumption simultaneously in lower leg during recovery from plantar flexion exercises. The feasibility and reproducibility of the proposed method is demonstrated in six healthy subjects. This method will shed light on the interplay between muscle function and substrate delivery and will lead to new pathways to exploit for diagnostics and therapeutics.

Scott A Reid¹, Kevin F King², David J Lomas³, Florine van der Wolf-de Lijster³, Lloyd Estkowski², and Martin J Graves^3
1GE Healthcare, Chalfont St Giles, United Kingdom, ²GE Healthcare, Waukesha, Wisconsin, United States, ³Radiology, Addenbrooke's Hospital & University of Cambridge, Cambridge, Cambridgeshire, United Kingdom

Multi-slice 2D FS PD sequence tends to be the sequence of choice for PD Fat Sat of the knee due to the relatively long scan times (5-6 minutes) and risk of motion artefacts associated with 3D PD FS imaging sequence. However a 3D sequence can offer an increase in coverage as well as SNR. Here we developed a PD FS 3D FSE sequence, which was modified to perform random CS undersampling followed by a custom reconstruction algorithm. In total 12 asymptomatic knees were imaged using the standard 3D PD Fat Sat protocol compared to the 3D PD Fat Sat with CS. The results showed that in all 12 knees the CS sequence reduced the scan time by 50% as well as providing diagnostic image quality.

Michael Paul Recht¹, Ricardo Otazo², Leon Rybak², Soterios Gyftopoulos², Catherine Petchprapa², Christian Geppert³, Mary Bruno², and Esther Raithel^3
1Radiology, NYU School of Medicine, New York, New York, United States, ²Radiology, NYU School of Medicine, New York, United States, ³Siemens Healthcare, Germany

A 3D TSE (SPACE) sequence using SPARSE-SENSE acceleration was optimized and compared to conventional multiplanar 2D TSE sequences in 21 patients for the evaluation of internal derangement of the knee. The optimized SPACE sequence demonstrated no statistically significant difference in sensitivity, specificity, or accuracy for the detection of meniscal or ligament tears when compared with the 2D TSE sequences using arthroscopy as the gold standard. If substantiated in larger clinical studies, this could lead to significant shortening of exam time, potentially enlarging the indication and utilization of knee MR as well as decreasing its cost.

Feliks Kogan¹, Jarrett Rosenberg¹, Sloane Brazina¹, Audrey Fan¹, Dawn Holley¹, and Garry Gold^1
1Department of Radiology, Stanford University, Stanford, CA, United States

MR hardware used during simultaneous PET/MR imaging with hybrid systems may affect both qualitative and quantitative accuracy of PET images. We measured the effect of a 16-channel flexible coil on measured PET SUV in a time-of flight PET/MR scan. Results showed that the coil had a minimal impact on SUV profiles and values in phantoms and in vivo in the knee.

Shihong Li¹, Guangwu Lin¹, Chuntao Ye¹, Haizhen Qian¹, Panli Zuo², Caixia Fu³, Yanqing Hua¹, David M. Grodzki⁴, and Ming Ji^1
1Radiology, Huadong Hospital, Fudan University, Shanghai, China, ²Siemens Healthcare, MR Collaborations NE Asia, Beijing, China, ³Application R&D Department, Siemens Shenzhen Magnetic Resonance Ltd., Shanghai, China, ⁴Magnetic Resonance, Siemens Healthcare, Erlangen, Germany

This is a primary study of in vivo morphological semi-quantitative assessment of knee osteoarthritis using dual-echo 3D UTE imaging which compared with traditional sequences

Joep van Oorschot¹, Mark Gosselink¹, Fredy Visser², Alexandra de Rotte¹, Peter Luijten¹, and Dennis Klomp^1
1University Medical Center Utrecht, Utrecht, Utrecht, Netherlands, ²Philips Healthcare, Best, Noord-Brabant, Netherlands

T1ρ-mapping is a promising quantitative technique to detect cartilage damage at an early stage, at which tissue damage might be reversible. Here we test the feasibility of high resolution T1ρ-mapping mapping of articular cartilage at 3T. T1ρ-mapping was performed using a T1ρ-prepared 3D FFE sequence. 4 images with different spin-lock (SL) preparation times with an amplitude of 500 Hz were acquired (SL = 1,12,24,48 ms). The T1ρ-relaxation time in the articular cartilage in healthy subjects was 57±2 ms. High resolution T1ρ-mapping of the wrist at 3T is feasible, and a promising technique to assess early cartilage damage in the wrist.

Sarah L. Pownder¹, Kei Hayashi², Parina H. Shah¹, Hollis G. Potter¹, and Matthew F. Koff^1
1Department of Radiology and Imaging - MRI, Hospital for Special Surgery, New York, New York, United States, ²College of Veterinary Medicine, Cornell University, Ithaca, New York, United States

The canine species is commonly used as a preclinical model and understanding the normative and compartment dependent T2 values of the canine knee will be beneficial for longitudinal evaluation of osteoarthritis. T2 mapping was performed on the stifles of 7 dogs to evaluate the articular cartilage of the femoral trochlea, patella, femoral condyles, and tibial plateau. Differences of cartilage T2 values were found throughout the stifle joint with the lateral femoral condylar having the longest T2 values compared to the other regions of interest. The results provide a baseline of normative values for researchers in future preclinical studies.

Taiki Nozaki¹, Yasuhito Kaneko¹, Hon J. Yu¹, Kayleigh Kaneshiro¹, Ran Schwarzkopf², Takeshi Hara³, and Hiroshi Yoshioka^1
1Radiological Sciences, University of California, Irvine, Orange, California, United States, ²Orthopaedic Surgery, University of California, Irvine, Orange, California, United States, ³Intelligent Image Information, Gifu University Graduate School of Medicine, Gifu, Japan

T1rho-weighted MR imaging enables us to detect early cartilage degeneration in early osteoarthritis patients before appearing morphological change. However for the methodology of segmentation, the number of slices measured is only one or several slices, not all slices from the knee in most of reports, and there is no previous publication about normal entire femoral T1rho map profiles for analyzing regional or cartilage layer variations. The objective of this study was to create normalized T1rho profiles of healthy entire femoral cartilage with 3 dimensional angular and depth dependent analysis, and evaluate their usefulness.

Hongsheng Wang¹, Parina H. Shah², Suzanne Maher¹, Scott Rodeo³, Hollis G. Potter², and Matthew F. Koff^2
1Department of Biomechanics, Hospital for Special Surgery, New York, New York, United States, ²Department of Radiology and Imaging - MRI, Hospital for Special Surgery, New York, New York, United States, ³Sports Medicine and Shoulder Service, Hospital for Special Surgery, New York, New York, United States

Articular cartilage deformation within a joint may be predictive of cartilage health and predisposition to further degeneration. In this study, we evaluated a displacement controlled MR compatible loading device to apply an axial load to the knee joint during MR image acquisition. The repeatability of knee positioning was assessed by collecting repeated scans from four healthy volunteers and was determined to be within 1 mm of translation and 2 degrees of rotation. It was also determined that reproducible measurements of cartilage deformation may be obtained by pre-loading the lower limb for at least 12 minutes.

Thomas Lange¹, Michael Herbst^1,2, Benjamin R. Knowles¹, Kaywan Izadpanah³, and Maxim Zaitsev^1
1Department of Radiology, Medical Physics, University Medical Center Freiburg, Freiburg, Germany, ²John A. Burns School of Medicine, University of Hawaii, Honolulu, Hawaii, United States, ³Department of Orthopedic and Trauma Surgery, University Medical Center Freiburg, Freiburg, Germany

Cartilage T2 has been established as a sensitive biomarker, which correlates with collagen microarchitecture and water content and is thus susceptible to loading. In this work, we demonstrate robust T2 mapping of the patellofemoral cartilage with in situ mechanical loading, using prospective motion correction of load-induced subject motion. T2 maps are reconstructed from multiple spin-echo data for scans with slice position updates before every excitation and scans with additional inter-echo correction. While uncorrected images show considerable motion artifacts giving rise to erroneous cartilage T2 mapping results, these artifacts can be efficiently suppressed with prospective motion correction.

Yasuhito Kaneko¹, Taiki Nozaki¹, Hon Yu¹, Kayleigh Kaneshiro¹, Ran Schwarzkopf², Takeshi Hara³, and Hiroshi Yoshioka^1
1Radiological Sciences, University of California, Irvine, Orange, CA, United States, ²Orthopaedic Surgery, University of California, Irvine, Orange, CA, United States, ³Division of Regeneration and Advanced Medical Sciences, Gifu University Graduate School of Medicine, Gifu, Japan

In this study we created normal T2 map profiles from the entire femoral cartilage of 20 healthy volunteer knees to assess regional variations using a novel angle/layer dependent approach. Overall, variations were observed in inter- and intra-rater reliability by location, and in T2 values by angular orientation to B0 and layers of the cartilage. The results indicate the importance of evaluating cartilage in consideration of these variations for diagnosis of cartilage degeneration in specific location of the knee.

Volkan Emre Arpinar¹, Weitian Chen², and L Tugan Muftuler^1,3
1Department of Neurosurgery, Medical College of Wisconsin, Milwaukee, Wisconsin, United States, ²Global Applied Science Laboratory, GE Healthcare, California, United States, ³Center for Imaging Research, Medical College of Wisconsin, Milwaukee, WI, United States

It was shown that MRI T1Rho images could be used to assess proteoglycan loss; therefore, it can be employed as a quantitative measure of intervertebral discs (IVD) degeneration, especially in early stages. In order to use T1Rho as a diagnostic or prognostic tool, however, one needs to assess the reproducibility of these measurements. Moreover, earlier studies showed diurnal changes in the IVDs during rest and loading conditions. Therefore the goal of this work was to assess the reproducibility and diurnal changes in T1Rho measurements in the IVDs.

Jan Rieger¹, Claudia Kronnerwetter², Andreas Graessl³, Helmar Waiczies¹, Roman Leicht¹, Beate Endemann³, Siegfried Trattnig², and Thoralf Niendorf^3,4
1MRI.TOOLS GmbH, Berlin, Berlin, Germany, ²High Field MR Centre, Department of Biomedical Imaging und Image-guided Therapy, Medical University of Vienna, Vienna, Vienna, Austria,³Berlin Ultrahigh Field Facility (B.U.F.F.), Max-Delbrueck-Center for Molecular Medicine, Berlin, Berlin, Germany, ⁴Experimental and Clinical Research Center, a joint cooperation between the Charité Medical Faculty a, Berlin, Berlin, Germany

Magnetic resonance imaging at 1.5 T and 3.0 T is the primary modality for the evaluation of the temporo-mandibular joint (TMJ). It remains challenging due to subtle anatomical structures and susceptibility artifacts of inner and middle ear. These constraints translate into stringent technical requirements for RF coil design. To advance the capabilities of high spatial resolution TMJ imaging this study proposes an 8 channel transmit/receive coil for dedicated MRI of the TMJ. The RF coil array’s performance and safety are evaluated in simulations. The RF coils applicability for sub-millimeter spatial resolution TMJ MRI is examined in vivo at 7.0 T.

Sarah L. Pownder¹, Parina H. Shah¹, Kei Hayashi², Hollis G. Potter¹, and Matthew F. Koff^1
1Department of Radiology and Imaging - MRI, Hospital for Special Surgery, New York, New York, United States, ²College of Veterinary Medicine, Cornell University, Ithaca, New York, United States

Canine models of anterior cruciate ligament reconstruction are commonly used to compare different reconstruction techniques, with the posterior horn of the medial meniscus as a common site of injury resulting from knee instability. This study performed T2* regional mapping of the canine knee meniscus in 5 control subjects. The regions of interest (ROIs) were the anterior and posterior horns of the medial and lateral menisci. The results indicated prolonged T2* values in the posterior horn of the medial meniscus as compared to the remaining ROIs. The results provide a baseline of normative values for researchers in future preclinical studies.

Ju Chen¹, Qun He¹, Jihye Baek¹, Daryl D'Lima¹, Jiang Du¹, Nikolaus M. Szeverenyi¹, and Graeme Bydder^1
1University of California, San Diego, CA, United States

Bovine and human mensicus specimens were examined at 11.7T in order to demonstrate the vasculature of the meniscus. Multiple spin echo and gradient echo sequences showed high signal branching structures consistent with blood vessels and separable from radial ties or fibers. The vessels were generally interposed between radial and circumferential fibers and did not involve the more cartilaginous regions. The results are consistent with previous angiographic and microscopic studies and show that it may be possible to demonstrate vascular features at higher fields using clinical systems.

Valentina Mazzoli^1,2, Andre Sprengers³, Aart J. Nederveen², Gustav J. Strijkers^1,4, Klaas Nicolay¹, and Nico Verdonschot^3,5
1Biomedical NMR, Department of Biomedical Engineering, Eindhoven University of Technology, Eindhoven, Netherlands, ²Department of Radiology, Academic Medical Center, Amsterdam, Netherlands, ³Orthopaedic Research Lab, Radboud University Medical Center, Nijmegen, Netherlands, ⁴Biomedical Engineering and Physics, Academic Medical Center, Amsterdam, Netherlands, ⁵Laboratory of Biomechanical Engineering, University of Twente, Enschede, Netherlands

While the added value of dynamic MRI over conventional static imaging has already been demonstrated in several studies, dynamic imaging of soft tissues in the knee such as ligaments and tendons has been investigated less extensively, mostly due to the technical and practical challenge of dynamic fat suppressed imaging during movement of the knee joint. We present here a fast and robust technique for fat suppression to be used in real time imaging of the flexion/extension of the knee. Fat suppression allowed segmentation and evaluation of the posterior cruciate ligament pattern of elongation during flexion/extension.

Yoshikazu Okamoto¹, Kiyoshi Maehara¹, and Tetsuya Kanahori^1
1University of Tsukuba, Tsukuba, Ibaraki, Japan

Preliminary results of early detection of baseball elbow in Japanese elementary school boys and girls using low field magnetic resonance imaging specialized for small joints

Soterios Gyftopoulos¹, Konstantin Krepkin¹, Mary Bruno¹, and Jose G Raya^2
1Radiology, NYU Langone Medical Center, New York, NY, United States, ²Bernard and Irene Schwartz Center for Biomedical Imaging, New York University School Of Medicine, New York, Ny, United States

T2* and T2 maps have the potential to provide improved qualitative information on the status of the supraspinatus tendon which along with the morphologic findings provided by conventional MR imaging can provide a better understanding of the repairability of the injured tendon and, thus, the likelihood of success of the surgical repair.

Masaki Katsura^1,2, Yuichi Suzuki², Akihiro Kasahara², Harushi Mori¹, Akira Kunimatsu¹, Yoshitaka Masutani³, Masaaki Hori⁴, Shigeki Aoki⁴, and Kuni Ohtomo^1
1Radiology, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan, ²Radiology, The University of Tokyo Hospital, Tokyo, Japan, ³Intelligent Systems, Hiroshima City University, Hiroshima, Japan, ⁴Radiology, School of Medicine, Juntendo University, Tokyo, Japan

In the present study, we performed q-space imaging (QSI) analyses for lumbar intervertebral discs (IVDs) with different stages of degeneration. Our results suggest that the degenerative process of IVDs involves narrowing of the space for free water movement and a generally higher degree of microstructural complexity, in which we are unable to assess with conventional quantitative MR measurements. QSI may provide sensitive biomarkers for IVD degenerative microstructural changes and can potentially become an appropriate tool to allow characterization of various IVD pathologies.

Ephraim I Ben-Abraham¹, Jun Chen², and Richard L Ehman^2
1Mayo Graduate School, Mayo Clinic, Rochester, Minnesota, United States, ²Radiology, Mayo Clinic, Rochester, MN, United States

Low back pain (LBP) is a very costly and prevalent health disorder in the U.S. Spinal instability and degenerative disc disease are two of the most common causes of LBP. It is known that the stiffness of the disc changes substantially with degeneration. MRE has been demonstrated for estimating the shear stiffness of the nucleus in the intervertebral disc in vitro. In this study, we attempt to measure spinal instability in an in vitro goat spine segment with induced disc degeneration and mechanical destabilization. Our results suggest MRE may be capable of detecting spinal instability.

Thomas Baum¹, Samuel P Yap¹, Michael Dieckmeyer¹, Stefan Ruschke¹, Holger Eggers², Hendrik Kooijman³, Ernst J Rummeny¹, Jan S Bauer⁴, and Dimitrios C Karampinos^1
1Department of Radiology, Klinikum rechts der Isar, Technische Universitaet Muenchen, Munich, Germany, ²Philips Research Laboratory, Hamburg, Germany, ³Philips Healthcare, Hamburg, Germany, ⁴Section of Neuroradiology, Klinikum rechts der Isar, Technische Universitaet Muenchen, Munich, Germany

There is a growing interest in vertebral bone marrow tissue as anatomical compartment that contributes to systemic and bone metabolism. Bone marrow adiposity is associated with visceral adipose tissue and HbA1c values in women with type 2 diabetes mellitus, chemotherapy and radiation treatment-induced bone marrow damage, and bone loss pathophysiology. Chemical shift encoding-based water-fat imaging has been emerging to measure vertebral bone marrow proton density fat fraction (PDFF). In this study, we assessed the anatomical variation of PDFF over the whole spine and provided a reference database of PDFF values of young, healthy subjects, which has not been established yet.

Yi-Xiang Wang¹, Greta SP Mok², Duo Zhang², Shu-Zhong Chen¹, and Jing Yuan^3
1Dept Imaging and Interventional Radiology, The Chinese University of Hong Kong, Shatin, NT, Hong Kong, ²Department of Electrical and Computer Engineering, University of Macau, Macau SAR, Macau, ³Medical Physics and Research Department, Hong Kong Sanatorium & Hospital, Happy Valley, Hong Kong

We compared three region-of-interest (ROI) methods for nucleus pulposus (NP) and annulus fibrosus (AF). Fifty-two subjects were imaged under a 3-T MRI and a total of 256 discs were evaluated using manual and uniform ROI methods to define NP and AF. The intra-class correlation coefficient (ICC) values were all >0.75 when comparing 5-/7-ROI with manual ROI methods for NP, and 0.167-0.488 for AF when comparing 7-ROI with M-ROI method. The values increased to 0.378-0.582 for 5-ROI method. Comparable results were obtained with Bland-Altman plots. The uniform ROI methods agreed well with manual ROI for NP but not for AF.

Yifei Liu¹, Julia Zelenakova², Kejia Cai^2,3, Robert Kleps⁴, Thomas J Royston^1,2, Richard L Magin², Andrew Larson⁵, and Weiguo Li^4,5
1Department of Mechanical & Industrial Engineering, University of Illinois at Chicago, Chicago, Illinois, United States, ²Department of Bioengineering, University of Illinois at Chicago, Chicago, Illinois, United States, ³Department of Radiology, University of Illinois at Chicago, Chicago, IL, United States, ⁴Research Resource Center, University of Illinois at Chicago, Chicago, Illinois, United States, ⁵Department of Radiology, Northwestern University, Chicago, Illinois, United States

Biomechanical properties of the intervertebral disk (IVD) can be a potential biomarker to access IVD degeneration, one of most significant causes of lower back pain. This study shows the feasibility and promising results of using magnetic resonance elastography (MRE), a non-invasive tissue stiffness estimation technique, to measure the IVD stiffness in a lumbar segment of a rat model.

Wingchi Edmund Kwok^1,2 and Terry K Koo^3
1Department of Imaging Sciences, University of Rochester, Rochester, NY, United States, ²Rochester Center for Brain Imaging, University of Rochester, Rochester, NY, United States,³Department of Research, New York Chiropractic College, Seneca Falls, NY, United States

Since conventional MRI cannot easily distinguish cortical bone from neighboring tissues such as tendons, ligaments and articular capsule, we evaluated the use of UTE imaging for improved visualization and segmentation of vertebrae. The study was conducted on a 3T system on two normal subjects using a work-in-progress 3D UTE sequence from Siemens. CISS images were also obtained for comparison. The results showed that UTE better distinguished cortical bone from other tissues, enabling easier segmentation of the vertebrae. UTE imaging may be useful for functional, developmental and diagnostic assessment of spine, such as the studies of scoliotic deformities or osteophyte formation.

Miyuki Takasu¹, Yuji Akiyama¹, Ryuji Akita¹, Kazushi Yokomachi¹, Yoko Kaichi¹, Shuji Date¹, Masatoshi Honda², and Kazuo Awai^1
1Diagnostic Radiology, Hiroshima University Hospital, Hiroshima, Hiroshima, Japan, ²Philips Electronics, Tokyo, Japan

Clinical studies using different methods including MRS to assess marrow fat have found a negative correlation with BMD. The present cadaveric study was conducted in order to validate the relationships among vertebral marrow fat, BMD, and bone strength. Values of fat fraction assessed with mDIXON correlated with those from 1H MRS. There was a negative correlation between marrow fat and tissue BMD. This relationship can also be assessed by the mDIXON technique. Further study is needed to assess the feasibility of using mDIXON for quantification of vertebral marrow fat in vivo.

Delphine Perie¹, Pierre-Francois Beauchemin¹, Phil Bayly², Joel R Garbow², John Schmidt², Ruth Okamoto², and Farida Cheriet^1
1Mechanical Engineering, Polytechnique Montreal, Montreal, Quebec, Canada, ²Mechanical Engineering and Materials Science, Washington University in St. Louis, Saint Louis, Missouri, United States

Aging and degeneration have been shown to be associated with changes in intervertebral disc mechanical properties, generating interest in the use of mechanical properties to establish early biomarkers for the degenerative cascade. This study demonstrated that global mechanical characterization of the intervertebral disc, including both nucleus pulposus and annulus fibrosus, was possible with high frequency needle magnetic resonance elastography. The advantages and limitations of different approaches to the inversion problem in the intervertebral disc were also determined. The developed method could be adapted in vivo to assess the contribution of osmotic pressure to the mechanical behavior of the intervertebral disc.

Tsutomu Inaoka¹, Masayuki Odashima¹, Mitsuyuki Tozawa¹, Hiroyuki Nakazawa¹, Masahiro Sogawa¹, Tomoya Nakatsuka¹, Rumiko Kasai¹, and Hitoshi Terada^1
1Radiology, Toho University Sakura Medical Center, Sakura, Chiba, Japan

There has recently been an increased interest in diagnosing abnormalities of the brachial plexus with MRI. STIR is often used in assessing the brachial plexus since chemical saturation techniques may be insufficient for homogenous fat suppression. On STIR images, however, some vessels including the internal jugular veins, paraspinal vessels, and others around the brachial plexus are hyperintense compared to the fat and surrounding tissues. Recently, blood-suppression pulse technique has been introduced to reduce signal intensities from vessels and microperfusion of the tissues at 3T MRI.The MIP image of 3D SPACE STIR technique with blood-suppression pulse is superior to that without. It might be a better way to evaluate anatomies and pathologies of the brachial plexus.

Ron N Alkalay¹, Carl-Fredrik Westin², Dominik Meier², and David B Hackney^3
1Orthopedics, Beth Israel Deaconess Medical Center, Boston, MA, United States, ²Radiology, Brigham and Women's Hospital, Boston, MA, United States, ³Radiology, Beth Israel Deaconess Medical Center, Boston, MA, United States

Human disks were MR imaged using T2map and MR diffusivity protocols under two load conditions and the disks dynamic and viscoelastic response quantified. Loading yielded significantly lower Mean Diffusivity and higher variance. No such changes were observed for T2map. Tissue based differences (Nucleus vs. Annulus) were observed for both measures, but only diffusivity detected the application of loading. MD correlated with the disks dynamic and viscoelastic response with T2 relaxation correlated with its dynamic and long-term viscoelastic response. The strong correlations between MD and disk mechanics suggest that MR might permit quantitative assessment of disk functional status and structural integrity.

Anette Karlsson^1,2, Anneli Peolsson³, Janne West^2,3, Ulrika Åslund³, Thobias Romu^1,2, Örjan Smedby^2,3, Peter Zsigmond⁴, and Olof Dahlqvist Leinhard^2,3
1Department of Biomedical Engineering, Linköping University, Linköping, Sweden, ²Center for Medcial Image Science and Visualization (CMIV), Linköping University, Linköping, Sweden,³Department of Medical and Health Sciences, Linköping University, Linköping, Sweden, ⁴Department of Neurosurgery and Department of Clinical and Experimental Medicine, Linköping University, Linköping, Sweden

The fatty infiltration of the multifidus muscle was investigated in 31 individuals with chronic Whiplash Associated Disorders (WAD) and 31 controls, matched for age and sex in C4-C7, using water-fat separated MRI. Individuals with severe disability had significantly (p=0.03 to 0.04) higher content of fatty infiltration on the right side of the neck compared to controls and to those with mild/ moderate WAD. There were no significant differences between those with mild/ moderate WAD and healthy controls. Earlier reported findings using T1-weighted MRI was reproduced also using water-fat separated MRI.

Chengyan Wang¹, Rui Zhang², Xiaodong Zhang³, He Wang⁴, Kai Zhao³, Jue Zhang^1,2, Xiaoying Wang^1,3, and Jing Fang^1,2
1Academy for Advanced Interdisciplinary Studies, Peking University, Beijing, Beijing, China, ²College of Engineering, Peking University, Beijing, China, ³Department of Radiology, Peking University First Hospital, Beijing, China, ⁴Philips Research China, Shanghai, Shanghai, China

Muscle BOLD MRI has been used to infer small vessel function following arterial occlusion, the infusion of vasoactive compounds and to study vascular function in peripheral artery disease. BOLD R2* is a summation of irreversible (R2) and reversible(R2¡¯) relaxation rates (R2*=R2+R20). It has been suggested that R2 is sensitive to many physiological perturbations, including tissue water content, inflammation and changes in tissue oxygenation. However, R2¡¯ is linearly dependent on tissue oxygenation. Therefore, R2¡¯ is able to provide a more specific and direct evaluation of muscle oxygenation. Muscle BOLD MRI has been used to infer small vessel function following arterial occlusion, the infusion of vasoactive compounds and to study vascular function in peripheral artery disease. BOLD R2* is a summation of irreversible (R2) and reversible(R2¡¯) relaxation rates (R2*=R2+R20). It has been suggested that R2 is sensitive to many physiological perturbations, including tissue water content, inflammation and changes in tissue oxygenation. However, R2¡¯ is linearly dependent on tissue oxygenation. Therefore, R2¡¯ is able to provide a more specific and direct evaluation of muscle oxygenation.

Linda Heskamp¹, Barbara Helena Janssen¹, and Arend Heerschap^1
1Radiology, Radboud university medical center, Nijmegen, Netherlands

The aim of this study was to assess the reproducibility of quantitative T2-MRI determined muscular fat fraction in patients with fascioscapulohumeral muscular dystrophy (FSHD) and healthy volunteers. Fat content was derived from multi spin-echo images of 80 FSHD muscles and 45 healthy volunteer muscles by fitting the signal-intensity to a bi-exponential function with fixed T2 times for muscle and fat. Reproducibility was assessed by a Bland-Altman analysis. The coefficient of repeatability for FSHD muscles and healthy muscles were 6.5% (1.96*SD) and 2.8% (1.96*SD), respectively. With this reproducibility, treatment effects of 2.5% can be detected in a patient cohort < 10.

William D. Rooney¹, Yosef Berlow¹, Sean C. Forbes², Rebecca J. Willcocks², James Pollaro¹, William T. Triplett³, Dah-Jyuu Wang⁴, Barry J. Byrne⁵, Richard Finkel⁶, Barry S. Russman⁷, Erika L. Finanger⁷, Michael J. Daniels⁸, H. Lee Sweeney⁹, Glenn A. Walter³, and Krista H. Vandenborne^2
1Advanced Imaging Research Center, Oregon Health & Science University, Portland, Oregon, United States, ²Department of Physical Therapy, University of Florida, Gainesville, Florida, United States, ³Physiology and Functional Genomics, University of Florida, Gainesville, Florida, United States, ⁴Department of Radiology, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania, United States, ⁵Department of Pediatrics, University of Florida, Gainesville, Florida, United States, ⁶Department of Neurology, Nemours Children's Hospital, Orlando, Florida, United States, ⁷Shriners Hospital, Portland, Oregon, United States, ⁸Division of Statistics & Scientific Computation, University of Texas, Austin, Texas, United States, ⁹Department of Pharamcology and Therapeutics, University of Florida, Gainesville, Florida, United States

Duchenne muscular dystrophy (DMD) is a progressive disease of which there is no cure. There is a need for biomarkers that are sensitive to progression, non-invasive, have excellent precision, and are easily transferable between institutions. MRI and MRS can be used to characterize muscle for detection of DMD pathology. The goal here is to identify biomarkers, characterize patterns of muscle involvement, and summarize DMD progression using a modeling approach utilizing MRI and MRS data.

Joshua Park¹, Jacqueline Wicki², Sue Knoblaugh³, Jeffrey Chamberlain^2,4, and Donghoon Lee^1
1Radiology, University of Washington, Seattle, WA, United States, ²Neurology, University of Washington, Seattle, WA, United States, ³Fred Hutchinson Cancer Research Center, Seattle, WA, United States, ⁴Biochemistry, University of Washington, Seattle, WA, United States

Multi-parametric MRI was performed to monitor disease progression and responses to adeno-associated viral (AAV) vector-mediated gene therapy for mice with muscular dystrophy. We quantified T2, magnetization transfer ratio and apparent diffusion coefficients along with 3 dimensional volume measurements for the monitoring. Mice were imaged at 3 months of age for pre-treatment and post-treatment at 8, 16 and 24 week time points. Histopathology was also conducted for tissues collected from the hindlimbs after the final time point for comparison. T2 relaxation, alongside diffusion and magnetization transfer effects provides useful data towards the goal of non-invasively monitoring the treatment of muscular dystrophy.

Felix T Kurz¹, Thomas Kampf², Lukas R Buschle³, Sabine Heiland⁴, Martin Bendszus⁴, and Christian H Ziener^1,3
1Heidelberg University, Heidelberg, BW, Germany, ²University of Wuerzburg, Bavaria, Germany, ³German Cancer Research Center, Heidelberg, BW, Germany, ⁴Heidelberg University, BW, Germany

Capillary networks in muscle tissue are examined using Krogh’s capillary model and it is shown that diffusion-dependent CPMG relaxation rates depend on microstructural parameters such as capillary radius, nuclear spin diffusion and regional blood volume fraction. The findings agree well with experimental data and can be used to quantify microstructural parameters that correlate with denervation- or age-related microcirculatory remodeling in skeletal muscle.

Linda Heskamp¹, Barbara H. Janssen¹, and Arend Heerschap^1
1Radiology, Radboud university medical center, Nijmegen, Netherlands

The aim of this study was to develop a method to quantify measures of severity of inflammation as seen on TIRM images in patients with fascioscapulohumeral muscular dystrophy (FSHD). Intensity (in standardized z-scores) and volume of inflammation were quantified on TIRM images in six muscles of three patients at baseline and follow-up. We observed that three processes occurred over time. The volume and intensity of inflammation both 1) increased, 2) decreased, 3) volume decreased, while intensity increased. Thus, the proposed method is able to quantify features of the inflammatory process in FSHD patients, which may be valuable to evaluate treatment.

Didier Laurent¹, Attila Nagy², Steve Pieper², Harlem Gongxeka¹, Celeste Pretorius¹, and Stefan Baumann^1
1Biomarker Department, Novartis, Basel, Switzerland, ²Isomics, Inc, Cambridge, Ma, United States

A 3D semi-automated segmentation approach was developed and validated for quick and accurate determination of individual thigh muscle volumes from magnetic resonance (MR) image series of both healthy individuals and patients with sporadic inclusion body myositis (sIBM). Specific muscles of sIBM patients displayed clear signs of atrophy, more so in the anterior compartment of the thigh, along with up to 50% of infiltrated fat, which might explain propensity of these patients to loose balance.

Prashant Bansal¹, David Bennett¹, Xiaodong Tao¹, and Sally Warner^1
1Medical Imaging, PAREXEL Informatics, Billerica, MA, United States

When applied to images with signal inhomogeneity, the N4ITK algorithm can correct images by use of a calculated bias field. Herein, we demonstrate that use of a batch-scripted N4ITK algorithm implemented in 3DSlicer freeware leads to a significantly more efficient workflow for thigh muscle MR image processing. Customized automation and N4ITK batch processing through 3DSlicer is possible for efficient image inhomogeneity correction in large data sets common to clinical multi-site imaging trials. In addition, the N4ITK intensity inhomogeneity correction step results in quicker turnaround and efficient implementation of the automated and semi-automated segmentation tools resulting in reliable & faster segmentation in thigh muscle MRI data sets.

Carlos J Perez-Torres¹, Neva B Watson², Yong Wang^1,3, Paul T Massa^2,4, and Sheng-Kwei Song^1,3
1Radiology, Washington University, St. Louis, MO, United States, ²Microbiology & Immunology, SUNY Upstate Medical University, Syracuse, NY, United States, ³Hope Center for Neurological Disorders, Washington University, St. Louis, MO, United States, ⁴Neurology, SUNY Upstate Medical University, Syracuse, NY, United States

Once considered a tropical disease, infectious myositis is an underappreciated emerging global affliction. Diffusion basis spectrum imaging (DBSI) has been previously utilized to separately quantify inflammatory pathology and fiber pathology in white matter diseases such as multiple sclerosis. The present work is the first example of DBSI being applied to muscle pathology. DBSI-derived restricted isotropic diffusion is usually associated with increased immune cell infiltration. The restricted fraction increased in both lesion and normal-appearing muscle. At first glance, DBSI seems capable of detecting inflammation in the muscle that might be missed by just looking at ADC or FA.

Gregory Lemberskiy^1,2, Dmitry Novikov¹, Mary Bruno¹, Els Fieremans¹, and Soterios Gyftopoulos^1
1Bernard and Irene Schwartz Center for Biomedical Imaging, Department of Radiology, New York University School of Medicine, New York, NY, United States, ²Sackler Institute of Graduate Biomedical Sciences, New York University School of Medicine, New York, NY, United States

We show that modeling myofiber diameter using time dependent diffusion is feasible in the rotator cuff by comparing the diameters of the infraspinatus and supraspinatus across 10 shoulders. Fiber diameters in 2 clinical patients with full thickness tears were quantified longitudinally within 2 weeks prior to surgery and 3 months after surgery. Our method showed a systematic drop in fiber diameter after 3 months indicating that the model could serve as a biomarker for atrophy consequently and surgical outcome.

Sean C Forbes¹, Jingfeng Ma¹, Glenn A. Walter¹, Krista Vandenborne¹, and Song Lai^1
1University of Florida, Gainesville, Florida, United States

In this study we tested the feasibility of pseudo-continuous arterial spin labeling (pCASL) MRI to measure changes in skeletal muscle perfusion following a short high-intensity dorsiflexion exercise protocol. PCASL detected increases in perfusion of the primary dorsiflexors (tibialis anterior and extensor digitorum longus) after the contractions, and the perfusion values were shown to have good day-to-day reproducibility. This study shows the feasibility of applying pCASL to measure skeletal muscle perfusion after isometric fatiguing dorsiflexion contractions in healthy adults.

Marko Hoehne^1,2, Andreas Graessl², Jan Rieger³, Antje Els⁴, Beate Endemann⁴, Thomas Herold⁵, and Thoralf Niendorf^4,6
1HELIOS Klinikum Berlin Buch, Berlin, Berlin, Germany, ²Berlin Ultrahigh Field Facility (B.U.F.F.), Max Delbrück Center for Molecular Medicine (MDC), Berlin, Berlin, Germany, ³MRI.TOOLS GmbH, Berlin, Germany, ⁴Berlin Ultrahigh Field Facility (B.U.F.F.), Max Delbrück Center for Molecular Medicine (MDC), Berlin, Germany, ⁵HELIOS Klinikum Berlin Buch, Berlin, Germany,⁶Experimental and Clinical Research Center (ECRC), Charite Campus Berlin Buch, Humboldt-University, Berlin, Germany

MR imaging (MRI) of the shoulder is the method of choice in clinical practice. In common use is MRI with field strength of 1.5T and 3T and the normal anatomic structures are readily identifiable in these field strength. But especially lesions or fiber structures are difficult to localize. With special coil elements 7T MRI offers the potential to increase the identification of capillary structures and this even with a higher spatial resolution in submilimeter compartment.

Joshua Park¹, Martin Childers², and Donghoon Lee^1
1Radiology, University of Washington, Seattle, WA, United States, ²Rehabilitation Medicine, University of Washington, Seattle, WA, United States

Multi-parametric MRI was performed on a 3T MR human scanner to monitor disease progression and responses to adeno-associated viral (AAV) vector-medicated gene therapy for dogs with X-linked myotubular myopathy (XLMTM). We quantified T2 and apparent diffusion coefficients along with 3 dimensional volume measurements for the monitoring. Histopathology was also conducted for tissues biopsized from the hindlimbs after MRI for comparison. T2 relaxation, alongside diffusion effect provides useful data towards the goal of non-invasively monitoring the treatment of XLMTM. To our knowledge, this is the first MRI study to assess the disease and treatment responses for the canine model of XLMTM.

Anne Tonson^1,2, Jonathan Kasper^1,2, Ronald A Meyer^3,4, and Robert W Wiseman^2,3
1Physiology Department, Michigan State University, East Lansing, MI, United States, ²Biomedical Imaging Research Center, Michigan State University, East Lansing, MI, United States,³Physiology and Radiology Departments, Michigan State University, East Lansing, MI, United States, ⁴Biomedical Imaging Research Center, East Lansing, MI, United States

This study aimed to investigate the effect of skeletal muscle workload on local muscle blood flow and the corresponding time-course of flow recovery in the rat hindlimb using 2D_ PC-MRA measurements in the femoral vein. The present results showed a significant increase in flow from baseline in response to contraction regardless of the intensity. The corresponding change was lower for non- fatiguing stimulation (≤1Hz) compared to fatiguing contraction (≥2Hz) for which we also observed a reactive hyperemia. This study shows that MRI-based regional blood flow measurement can be used for the quantitative investigation of post-contraction time-course of flow recovery

Reinhard Rzanny¹, Patrick Hiepe¹, Kevin Tschiesche¹, Alexander Gussew¹, and Norman Stutzig^2
1AG Medical Physics, University Hospital Jena, Jena, Thüringen, Germany, ²Institute of Sport- and Movement science, University of Stuttgart, Stuttgart, Baden-Würtemberg, Germany

Functional T2w-MRI is used to depict activated muscle area in the calf muscle after electromyographic stimulation (EMS). By the example of the calf muscle and by using strong stimulation levels it should be investigated whether the activated muscle area only depends on the distance to the stimulating electrode or whether selective stimulations of the M. gastrocnemius as an individual muscles is possible.

Yoshikazu Okamoto¹, Shintaro Mori¹, Tomonori Isobe¹, Yuji Hirano¹, Hiroaki Suzuki¹, and Manabu Minami^1
1University of Tsukuba, Tsukuba, Ibaraki, Japan

Is intramyocellular lipid a diffusion-restricting factor in skeletal muscle cells?

Ravneet Vohra¹, Sean Forbes², Krista Vandenborne³, Elizabeth Mcnally⁴, and Glenn Walter^5
1Physiology and Functional Genomics, University of Florida, Gainesville, Florida, United States, ²Physical Therapy, University of Florida, Gainesville, Florida, United States, ³Physical Therapy, University of Florida, Florida, United States, ⁴Department of Medicine, University of Chicago, Chicago, Illinois, United States, ⁵Physiology and Functional Genomics, Unversity of Florida, Gainesville, Florida, United States

Mutations in the genes encoding dystrophin and its associated proteins cause muscular dystrophies, which are characterized by progressive muscle weakness and replacement by fibrotic tissue. Genetic modifiers have been shown to influence phenotypic variability both in humans and animal models. In animal models genetic modifiers can be studied by knocking out the same gene on different background of mouse strain. Murine models of muscular dystrophy on typical C57 background show relatively less severity over their life span compared to mouse models on DBA/2 background. In this study we used magnetic resonance to characterize murine models of dystrophy on DBA background.

Andrew D Davis¹ and Michael D Noseworthy^2,3
1Medical Physics and Applied Radiation Sciences, McMaster University, Hamilton, Ontario, Canada, ²Electrical and Computer Engineering, McMaster University, Ontario, Canada, ³School of Biomedical engineering, McMaster University, ON, Canada

Gradient echo echo planar imaging (GRE-EPI) has often been used to assess skeletal muscle, but not with regards to muscle displacement. Muscle displacement causes a signal re-saturation effect during GRE-EPI scanning. In this study, GRE-EPI time series were acquired, and post-exercise images were processed voxel-wise to assess the saturation effect present. Muscle displacement maps were generated from the post-processing scheme. The maps were examined for motion direction and proximity to the deep aponeuroses of the triceps surae muscles, and were found to agree with expectations for the plantar flexion exercise performed.

Yasuharu Watanabe¹, Keisaku Kimura², Masahiro Umeda¹, Tomokazu Murase³, Toshihiro Higuchi³, Chuzo Tanaka³, and Shoji Naruse^4
1Medical Infomatics, Meiji University of Integrative Medicine, Kyoto, Japan, ²Health Promoting and Preventive Medicine, Meiji University of Integrative Medicine, Kyoto, Japan,³Neurosurgery, Meiji University of Integrative Medicine, Kyoto, Japan, ⁴Health Care and Checkup, Daini Okamoto General Hospital, Kyoto, Japan

This study aims to evaluate the influence of obesity on DTI findings based on the fat fraction and eigenvalues. A BMI of 25 kg/m2 was used to divide the subjects into an obesity group and a normal group. 6 ROIs on femur slices were set at the vastus lateralis, vastus intermedius, vastus medialis, biceps femoris, semitendinosus, and semimembraneous muscles. The fat fraction was higher in the obesity group than in the normal group, with significant differences for VL, BF, and SM. The all eigenvalues were low value in the obesity group, with a significant difference between groups for VL.

Natalie M. Pizzimenti¹, Christiane Mallett², Robert W. Wiseman^1,2, and Erik M. Shapiro^2
1Physiology Department, Michigan State University, East Lansing, MI, United States, ²Radiology Department, Michigan State University, East Lansing, MI, United States

The purpose of this study was to investigate the ability of MSCs to differentiate into myogenic cells with varying magnetic labeling conditions. MSCs show morphological changes toward the myogenic lineage after 6 weeks in muscle media even with the introduction of magnetic particles. This is a new tool that will allow MRI-based cell tracking to further our understanding in skeletal muscle repair.

Kevin Tschiesche¹, Alexander Gussew¹, Maria Glöckner², Steffen Derlien², and Jürgen R Reichenbach^1
1Medical Physics Group, Institute of Diagnostic and Interventional Radiology, Jena University Hospital - Friedrich Schiller University Jena, Jena, Germany, ²Institute for Physiotherapy, Jena University Hospital - Friedrich Schiller University Jena, Jena, Germany

In the current study we monitored and directly compared local and global lactate changes in healthy volunteers by means of 1H MEGA-PRESS MRS and blood sampling, respectively, that were induced by exercising the calf muscle. Normalized ratios of lactate to creatine (Lac/Cr) as well as blood lactate concentrations both increased after the exercise indicating high anaerobic exercise conditions. However, different decay time constants of lactate were observed in muscle and blood, which can be ascribed to subsequent processes affecting the blood lactate time courses within the tissue.

Alireza Akbari¹, Dinesh Kumbhare^2,3, and Michael Noseworthy^4,5
1School of Biomedical Engineering, McMaster University, Hamilton, Ontario, Canada, ²Department of Medicine, University of Toronto, Ontario, Canada, ³University Health Network, Toronto Rehabilitation Institute, Ontario, Canada, ⁴Electrical and Computer Engineering, McMaster University, Ontario, Canada, ⁵School of Biomedical Engineering, McMaster University, Ontario, Canada

In this work we demonstrate the effects of calf muscle exercise on single and triple quantum filtered sodium spectroscopy.

Lukas Filli¹, Marco Piccirelli¹, David Kenkel¹, Roman Guggenberger¹, Gustav Andreisek¹, Val M Runge¹, and Andreas Boss^1
1University Hospital Zurich, Zurich, ZH, Switzerland

to be added

Reni Biswas¹, Karen Chen^2,3, Eric Y. Chang², Sheronda Statum¹, Won C. Bae¹, and Christine B. Chung^2,3
1Department of Radiology, University of California, San Diego, San Diego, CA, United States, ²VA San Diego Healthcare System, San Diego, CA, United States, ³University of California, San Diego, CA, United States

The TMJ has unique biomechanical characteristics, as the bilateral TMJs must function together under compressive loads while undergoing large-scale movement. MRI allows for noninvasive evaluation of the joint and has the ability to evaluate soft tissues such as the articular disc and its congruity relative to the condyle in closed and open mouth position. The biomechanics of the osseous structures in the normal TMJ are well demonstrated using high resolution dynamic 3D cube sequence and involves translation and rotation of the mandibular condyle in the anterior to posterior direction and tissue deformation due to compression.

Ladislav Valkovic^1,2, Marjeta Tušek Jelenc¹, Barbara Ukropcová^3,4, Wolfgang Bogner¹, Matej Vajda⁵, Thomas Heckmann⁶, Miroslav Baláž³, Marek Chmelík¹, Ivan Frollo², Norbert Bachl⁶, Jozef Ukropec³, Siegfried Trattnig¹, and Martin Krššák^1,7
1High Field MR Centre, Department of Biomedical Imaging and Image-guided Therapy, Medical University of Vienna, Vienna, Austria, ²Department of Imaging Methods, Institute of Measurement Science, Slovak Academy of Sciences, Bratislava, Slovakia, ³Obesity section, Diabetes and Metabolic Disease Laboratory, Institute of Experimental Endocrinology, Slovak Academy of Sciences, Bratislava, Slovakia, ⁴Institute of Pathophysiology, Faculty of Medicine, Commenius University, Bratislava, Slovakia, ⁵Faculty of Physical Education and Sport, Commenius University, Bratislava, Slovakia, ⁶Department of Sports and Physiological Performance, University of Vienna, Vienna, Austria, ⁷Division of Endocrinology and Metabolism, Department of Internal Medicine III, Medical University of Vienna, Vienna, Austria

This study aimed to assess the interrelations between measures derived from ³¹P-MRS in quadriceps femoris muscle at 7T in three physiologically different subject groups. Resting state alkaline Pi (Pi₂/Pi₁), phosphodiester concentration ([PDE]), Pi-to-ATP exchange rate constant assessed by saturation transfer and maximal mitochondrial capacity assessed by dynamic ³¹P-MRS during recovery from exercise were analyzed. Our results show that resting measurements of Pi₂/Pi₁ and [PDE] may provide an alternative biomarker of skeletal muscle mitochondrial capacity, complementing or overcoming the necessity of complex experimental set-up for dynamic examinations.

Mark S. Brown¹, Abhinav Gupta², Melanie Cree-Green², Gregory Coe², Amy Baumgartner², Bradley R Newcomer³, and Kristen J Nadeau^2
1Radiology, University of Colorado Anschutz, Aurora, CO, United States, ²Pediatrics, University of Colorado Anschutz, Aurora, CO, United States, ³Diagnostic and Clinical Sciences, University of Alabama, Birmingham, Alabama, United States

Insulin resistance (IR) is associated with mitochondrial dysfunction in adults with type 2 diabetes (T2D) but T2D in youth has a unique phenotype and is more common in females. We hypothesized that muscle IR, assessed using and hyperinsulinemic-euglycemic clamp techniques, would be associated with decreased mitochondrial function in adolescent females with T2D, as measured with dynamic 31P spectroscopy. T2D girls had slowed post-exercise ATP re-synthesis after exercise at an equal workload, relative to both lean and obese controls indicating decreased mitochondrial function following exercise. Further, rates of oxidative phosphorylation and mitochondrial capacity relate to insulin resistance in youth.