Journal articles: 'Ultra-short echo time (UTE)'

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Williams, A., Y. Qian, D. Bear, and C. R. Chu. "Assessing degeneration of human articular cartilage with ultra-short echo time (UTE) T2* mapping." Osteoarthritis and Cartilage 18, no. 4 (April 2010): 539–46. http://dx.doi.org/10.1016/j.joca.2010.02.001.

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Bracher, Anna-Katinka, Christian Hofmann, Axel Bornstedt, Saïd Boujraf, Erich Hell, Johannes Ulrici, Axel Spahr, Bernd Haller, and Volker Rasche. "Feasibility of ultra-short echo time (UTE) magnetic resonance imaging for identification of carious lesions." Magnetic Resonance in Medicine 66, no. 2 (February 28, 2011): 538–45. http://dx.doi.org/10.1002/mrm.22828.

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Delacoste, Jean, Jerome Chaptinel, Catherine Beigelman‐Aubry, Davide Piccini, Alain Sauty, and Matthias Stuber. "A double echo ultra short echo time (UTE) acquisition for respiratory motion‐suppressed high resolution imaging of the lung." Magnetic Resonance in Medicine 79, no. 4 (August 30, 2017): 2297–305. http://dx.doi.org/10.1002/mrm.26891.

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Łopuszyńska, Natalia, Krzysztof Szczepanowicz, Krzysztof Jasiński, Piotr Warszyński, and Władysław P. Węglarz. "Effective Detection of Nafion®-Based Theranostic Nanocapsules Through 19F Ultra-Short Echo Time MRI." Nanomaterials 10, no. 11 (October 26, 2020): 2127. http://dx.doi.org/10.3390/nano10112127.

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The application of the Three-Dimensional Ultra-Short Echo Time (3D UTE)pulse sequence at a high magnetic field for visualization of the distribution of 19F loaded theranostic core-shell nanocapsules with Nafion® (1,1,2,2-tetrafluoroethene; 1,1,2,2-tetrafluoro-2- [1,1,1,2,3,3-hexafluoro-3-(1,2,2-trifluoroethenoxy)propan-2-yl] oxyethanesulfonic acid) incorporated into the shell is presented. The nanocarriers were formed via the layer-by-layer technique with biodegradable polyelectrolytes: PLL (Poly-L-lysine), and with Nafion®: polymer with high 19F content. Before imaging, an MR (magnetic resonance) spectroscopy and T1 and T2 measurements were performed, resulting in values of T2 between 1.3 ms and 3.0 ms, depending on the spectral line. To overcome limitations due to such short T2, the 3D UTE pulse sequence was applied for 19F MR imaging. First Nafion® solutions of various concentrations were measured to check the detection limit of our system for the investigated molecule. Next, the imaging of a phantom containing core-shell nanocapsules was performed to assess the possibility of visualizing their distribution in the samples. Images of Nafion® containing samples with SNR ≥ 5 with acquisition time below 30 min for 19F concentration as low as 1.53 × 10−2 mmol 19F/g of sample, were obtained. This is comparable with the results obtained for molecules, which exhibit more preferable MR characteristics.

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Tbini, Zeineb, Mokhtar Mars, and Mouna Bouaziz. "T1 Relaxation Time of Achilles Tendon at 3 Tesla with Special Reference to Relevant Clinical Score: A Preliminary Study." Current Medical Imaging Formerly Current Medical Imaging Reviews 16, no. 2 (January 24, 2020): 164–73. http://dx.doi.org/10.2174/1573405615666181205130816.

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Purpose: The purpose of this study was to investigate T1 relaxation time of the human Achilles tendon, to test its short-term repeatability as well as the minimal detectable change, and to assess the extent that correlate with clinical symptoms. Methods: Twenty asymptomatic volunteers and eighteen patients with clinically and sonographically confirmed tendinopathy were scanned for ankle using a 3 Tesla (T) MR scanner. T1 maps were calculated from a variable flip angle gradient echo Ultra-short echo time sequence (VFA-GE UTE) and inversion recovery spin echo sequence (IR-SE) using a self-developed matlab algorithm in three regions of interest of Achilles Tendon (AT). Signal to Noise Ratio (SNR) between the two sequences was evaluated. INTRA-class Correlation Coefficient (ICC), Coefficient of Variation (CV) and the Least Significant Change (LSC) were calculated, to test short-term repeatability of T1. Subjects were assessed by the VISA-A clinical score. P values less than 0.005 were considered statistically significant. Results: Mean T1 values were 427.09 ± 53.37 ms and 528.70 ± 103.50 ms using IR-SE sequence and 575.43 ± 110.60 ms and 875.81 ± 425.77 ms with VFA-GE UTE sequence in the whole AT for volunteers and patients, respectively. : T1 values showed a significant difference between volunteers and patients (P=0.001). Regional variation of T1 in healthy and tendinopathic AT were greater for VFA-GE UTE sequence than for IR-SE sequence. VFA-GE UTE sequence showed clearly higher SNR compared to IR-SE sequence. Short-term repeatability of T1 values for volunteers showed an LSC of 22% and 14% for IR-SE sequence and VFA-GE UTE sequence, respectively. For patients, LSC was 14% and 5% for IR-SE sequence and VFA-GE UTE sequence, respectively. There was no correlation between T1 and VISA-A clinical score (p>0.005). Conclusion: VFA-GE UTE sequence used for T1 mapping calculation demonstrated short acquisition time and clearly high SNR. Results revealed that T1 relaxation time can be used as a biomarker to differentiate between healthy and pathologic Achilles tendon. However, T1 showed no correlation with the VISA-A clinical score.

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Delacoste, Jean, Helene Feliciano, Jérôme Yerly, Vincent Dunet, Catherine Beigelman‐Aubry, Giulia Ginami, Ruud B. van Heeswijk, Davide Piccini, Matthias Stuber, and Alain Sauty. "A black‐blood ultra‐short echo time (UTE) sequence for 3D isotropic resolution imaging of the lungs." Magnetic Resonance in Medicine 81, no. 6 (February 8, 2019): 3808–18. http://dx.doi.org/10.1002/mrm.27679.

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Schwaiger, Benedikt J., Charlotte Schneider, Sophia Kronthaler, Florian T. Gassert, Christof Böhm, Daniela Pfeiffer, Thomas Baum, et al. "CT-like images based on T1 spoiled gradient-echo and ultra-short echo time MRI sequences for the assessment of vertebral fractures and degenerative bone changes of the spine." European Radiology 31, no. 7 (January 14, 2021): 4680–89. http://dx.doi.org/10.1007/s00330-020-07597-9.

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Abstract Objectives To evaluate the performance of 3D T1w spoiled gradient-echo (T1SGRE) and ultra-short echo time (UTE) MRI sequences for the detection and assessment of vertebral fractures and degenerative bone changes compared with conventional CT. Methods Fractures (n = 44) and degenerative changes (n = 60 spinal segments) were evaluated in 30 patients (65 ± 14 years, 18 women) on CT and 3-T MRI, including CT-like images derived from T1SGRE and UTE. Two radiologists evaluated morphological features on both modalities: Genant and AO/Magerl classifications, anterior/posterior vertebral height, fracture age; disc height, neuroforaminal diameter, grades of spondylolisthesis, osteophytes, sclerosis, and facet joint degeneration. Diagnostic accuracy and agreement between MRI and CT and between radiologists were assessed using crosstabs, weighted κ, and intraclass correlation coefficients. Image quality was graded on a Likert scale. Results For fracture detection, sensitivity, specificity, and accuracy were 0.95, 0.98, and 0.97 for T1SGRE and 0.91, 0.96, and 0.95 for UTE. Agreement between T1SGRE and CT was substantial to excellent (e.g., Genant: κ, 0.92 [95% confidence interval, 0.83–1.00]; AO/Magerl: κ, 0.90 [0.76–1.00]; osteophytes: κ, 0.91 [0.82–1.00]; sclerosis: κ, 0.68 [0.48–0.88]; spondylolisthesis: ICCs, 0.99 [0.99–1.00]). Agreement between UTE and CT was lower, ranging from moderate (e.g., sclerosis: κ, 0.43 [0.26–0.60]) to excellent (spondylolisthesis: ICC, 0.99 [0.99–1.00]). Inter-reader agreement was substantial to excellent (0.52–1.00), respectively, for all parameters. Median image quality of T1SGRE was rated significantly higher than that of UTE (p < 0.001). Conclusions Morphologic assessment of bone pathologies of the spine using MRI was feasible and comparable to CT, with T1SGRE being more robust than UTE. Key Points • Vertebral fractures and degenerative bone changes can be assessed on CT-like MR images, with 3D T1w spoiled gradient-echo–based images showing a high diagnostic accuracy and agreement with CT. • This could enable MRI to precisely assess bone morphology, and 3D T1SGRE MRI sequences may substitute additional spinal CT examinations in the future. • Image quality and robustness of T1SGRE sequences are higher than those of UTE MRI for the assessment of bone structures.

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Tang, Peng, Jingtao Xu, Wei Liu, Yu Li, Wei Fan, and Xiaoliang Huang. "Study of the Feasibility of Conventional MR Images and Magnetic Resonance (MR)/Ultra-Short Echo Time (UTE) Technique in the Evaluation of Lumbar Disc Degeneration in the Axial Plane." Journal of Medical Imaging and Health Informatics 11, no. 3 (March 1, 2021): 817–21. http://dx.doi.org/10.1166/jmihi.2021.3360.

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The advantage and value of magnetic resonance (MR)-ultra-short echo time (UTE) technique in the displaying the structures of degenerative intervertebral discs were observed through evaluating the lumbar disc degeneration in the axial plane by conventional MR image and MR-UTE technique. A total of 160 examinees screened by inclusion and exclusion criteria were enrolled, and a total of 800 intervertebral disks were involved, and the degree of intervertebral disc degeneration was classified by conventional MR image classification method. After the first echo image of MR-UTE technique was integrated with the contour, the image entered UTE cartilage endplate, fibrous ring and osseous endplate. The integrity of the intervertebral disc from the above and below the intervertebral disc and the correlation of the structural endplate with the integrities of cartilage endplate, fibrous ring and osseous endplate under double echo sequence were analyzed, and the correlation analysis of the two categorical variables was conducted using rank correlation analysis. Under the MR-UTE sequence, there was no statistical significant difference in structural integrity constituent ratio (intact structure only on one side, incomplete structure on both side) between the non-low back pain group and the low back pain group (P > 0.05), the proportion of complete structure disappearance was lowest, and the proportion of partial structure disappearance was highest; there was a significant difference in the structural integrity of fibrous ring between the non-low back pain group and the low back pain group (P < 0.05), there was a statistical significant difference in structural integrity of fibrous rings between the two groups (P < 0.05); there was a statistical significant difference in pain degree between the partial structure disappearance group and the complete structure disappearance group (P < 0.05). There was no significant difference in pain degree between the groups (intact structure only on one side and incomplete structure on both side); conventional MR images showed no significant difference in the intervertebral disc degeneration degree between the non-low back pain group and low back pain group (P > 0.05), and the intervertebral disc degeneration degree had no significant correlation with the lower back pain. MR-UTE sequence and T2WI sequence showed that there was a correlation between different intervertebral disc degeneration degrees and the structural integrity distributions of cartilage endplate, osseous endplate and fibrous rings in two groups of patients with or without low back pain (P < 0.05). Whether low back pain exists or not has little effect on the intervertebral disc degeneration degree on T2WI. MR-UTE double echo sequence scan reveals that the intervertebral disc degeneration degree is positively related to the integrity and integrity distribution of cartilage endplate, fibrous ring and bone endplate.

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Takahashi, Masaya, Osamu Togao, Makoto Obara, Marc van Cauteren, Yoshiharu Ohno, Shigehiro Doi, Makoto Kuro-O, Craig Malloy, Connie C. Hsia, and Ivan Dimitrov. "Ultra-short echo time (UTE) MR imaging of the lung: Comparison between normal and emphysematous lungs in mutant mice." Journal of Magnetic Resonance Imaging 32, no. 2 (July 22, 2010): 326–33. http://dx.doi.org/10.1002/jmri.22267.

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Geibel, Margit-Ann, Benjamin Gelißen, Anna-Katinka Bracher, and Volker Rasche. "Artifact Properties of Dental Ceramic and Titanium Implants in MRI." RöFo - Fortschritte auf dem Gebiet der Röntgenstrahlen und der bildgebenden Verfahren 191, no. 05 (November 12, 2018): 433–41. http://dx.doi.org/10.1055/a-0755-2374.

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Aim Assessment of the visualization of titanium and ceramic dental implants using various isotropic three-dimensional magnetic resonance imaging (MRI) methods. Materials and Methods 21 dental implants (7 ceramic, 14 titanium) were scanned in vitro with a spatially isotropically resolved three-dimensional gradient echo (FFE), a turbo spin echo (SE) and an ultra-short-echo time (UTE) imaging technique. The resulting absolute volumes of the implants were quantified and the relative error to the theoretical volume was calculated. Results Ceramic implants and their periphery could be displayed well in all cases. The observed mean relative error results were 5.4 ± 2.3 % (UTE) to 6.5 ± 4.3 % (FFE). No significant difference was observed between the investigated MRI methods. The transition between implant and surrounding agarose could be shown in all cases without artifacts. Titanium implants resulted in mean relative errors between 1314 ± 350 % (FFE) and 2157 ± 810 % (SE). Here, significant differences were observed between the FFE and the SE and between the UTE and the SE sequence. The periphery of the implants could not be displayed in any case. Conclusion Use of the MRI technique for the diagnosis of peri-implantitis, the assessment of anatomical structures and planning of dental implantation is currently very limited but could be used more frequently, provided there are no disturbing or imaging-disturbing materials in the region of interest. MRI technology is not suitable in case of titanium implants. When using ceramic implants, MRI technology is an option. Key points Citation Format

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Abkai, Ciamak, Jan Hourfar, Jörg Glockengießer, Johannes Ulrici, Erich Hell, Volker Rasche, and Björn Ludwig. "Ultra short time to Echo (UTE) MRI for cephalometric analysis–Potential of an x-ray free fast cephalometric projection technique." PLOS ONE 16, no. 9 (September 13, 2021): e0257224. http://dx.doi.org/10.1371/journal.pone.0257224.

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Objectives A novel magnetic resonance imaging (MRI) scan protocol is presented on the basis of ultra-short time to echo (UTE). By this MRI cephalometric projections (MCPs) can be acquired without the need of post processing in one shot. Different technical parameterizations of the protocol are performed. Their impact on the performance of MCPs is evaluated in comparison to the gold standard–the lateral cephalometric radiography (LCR) for cephalometric analysis (CA) in orthodontics. Methods Seven MCPs with various scan parameters influencing the scan duration and one LCR are used from one subject. 40 expert assessors performed CA for 14 predefined cephalometric landmarks. Relative metric distances and absolute angular measurements were calculated. Statistical analysis is presented and the deviations are highlighted to demonstrate the potential of the method for further analysis. Results The MCPs are acquired in 5–154 seconds, depending on resolution and contrast. Mean relative distances were 2.4–2.7 mm in MCPs and 1.6 mm in LCR, which demonstrate the accuracy and level of agreement of the expert assessors in identifying anatomical landmarks. In comparison to other studies, the presented MCP performed similar in angular analysis and demonstrated on average deviation of 1.2° ±1.1° in comparison to LCR. Despite the point articulare (Ar) and the related gonial angle the calculate distances and angles show outcomes in the range of ±2°/2mm. Conclusions MCPs can be acquired much faster in comparison to other techniques known from literature for CA. This study demonstrated the potential of the new method and showed first feasible results. Further research is needed to analyze the performance on a broad range of patients.

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Krämer, Martin, Benedikt Herzau, and Jürgen R. Reichenbach. "Segmentation and visualization of the human cranial bone by T2* approximation using ultra-short echo time (UTE) magnetic resonance imaging." Zeitschrift für Medizinische Physik 30, no. 1 (February 2020): 51–59. http://dx.doi.org/10.1016/j.zemedi.2019.06.003.

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Togao, Osamu, Yoshiharu Ohno, Ivan Dimitrov, Connie C. Hsia, and Masaya Takahashi. "Ventilation/perfusion imaging of the lung using ultra-short echo time (UTE) MRI in an animal model of pulmonary embolism." Journal of Magnetic Resonance Imaging 34, no. 3 (July 14, 2011): 539–46. http://dx.doi.org/10.1002/jmri.22645.

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Ma, Yajun, Hyungseok Jang, Saeed Jerban, Eric Y. Chang, Christine B. Chung, Graeme M. Bydder, and Jiang Du. "Making the invisible visible—ultrashort echo time magnetic resonance imaging: Technical developments and applications." Applied Physics Reviews 9, no. 4 (December 2022): 041303. http://dx.doi.org/10.1063/5.0086459.

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Magnetic resonance imaging (MRI) uses a large magnetic field and radio waves to generate images of tissues in the body. Conventional MRI techniques have been developed to image and quantify tissues and fluids with long transverse relaxation times (T2s), such as muscle, cartilage, liver, white matter, gray matter, spinal cord, and cerebrospinal fluid. However, the body also contains many tissues and tissue components such as the osteochondral junction, menisci, ligaments, tendons, bone, lung parenchyma, and myelin, which have short or ultrashort T2s. After radio frequency excitation, their transverse magnetizations typically decay to zero or near zero before the receiving mode is enabled for spatial encoding with conventional MR imaging. As a result, these tissues appear dark, and their MR properties are inaccessible. However, when ultrashort echo times (UTEs) are used, signals can be detected from these tissues before they decay to zero. This review summarizes recent technical developments in UTE MRI of tissues with short and ultrashort T2 relaxation times. A series of UTE MRI techniques for high-resolution morphological and quantitative imaging of these short-T2 tissues are discussed. Applications of UTE imaging in the musculoskeletal, nervous, respiratory, gastrointestinal, and cardiovascular systems of the body are included.

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Orlandi, M., N. Landini, C. Nardi, G. Morana, S. Colagrande, and M. Matucci-Cerinic. "POS0384 ULTRA SHORT ECHO TIME MRI (UTE) SEQUENCE IN THE ASSESSMENT OF INTERSTITIAL DISEASE IN PATIENTS WITH SYSTEMIC SCLEROSIS: CORRELATION WITH DISEASE EXTENSION AT CT AND WITH PULMONARY LUNG FUNCTION TESTS." Annals of the Rheumatic Diseases 81, Suppl 1 (May 23, 2022): 446.2–447. http://dx.doi.org/10.1136/annrheumdis-2022-eular.4529.

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BackgroundInterstitial lung disease (ILD) is the major cause of death in Systemic sclerosis (SSc). Computed tomography (CT) is the gold standard imaging technique to diagnose ILD and to assess ILD prognosis. ILD extent assessment at lung CT has shown to correlate with functional lung capacity: extensive lung disease (> 20%) correlate with significant lung capacity decline (forced vital capacity ((FVC) <70%) that is, in fact, associated with a higher mortality. Unfortunately, it is burdened by exposure to ionizing radiations that limits its use for the follow-up. For this reason, new MRI sequences were recently investigated, and Ultra Short Echo Time (UTE) emerged promising for ILD assessment.ObjectivesThe aim of the study is to evaluate the reliability of an MRI-UTE sequence in the assessment of ILD extent in patients with SS in comparison with standard high-resolution CT images and to correlate the extension with pulmonary function tests (PFT).MethodsPatients with SSc and ILD underwent a CT and UTE-MRI (1.5 T) acquisition on the same day. In the same week, they carried out PFT, with FVC and the diffusion capacity of carbon monoxide (DLCo) evaluation. Two thoracic radiologists assessed in consensus, on CT and UTE-MRI, the extent of ILD. Extensions were calculated as the mean percentage of lung involvement, evaluated at five levels, with an approximation of 5%. ILD extension were classified as limited (<20%) or extensive (> 20% or 20% with FVC <70%). The ANOVA test was adopted to compare the CT and MRI extensions of the ILD. Correlations of the extent of CT and UTE-MRI alterations with FVC and DLCo were calculated with Pearson’s correlation coefficient r. Sensitivity, Specificity, Positive Predictive Value (PPV) and Negative Predictive Value (VPN) of UTE-MRI were also calculated for UTE-MRI in determining ILD extension.ResultsThe mean ILD extension was 20.9% in CT and 17.9 % in UTE-MRI (p-value=0.64). The correlation of ILD extension in CT with FVC and DLCo were significant (r=-0.66 (p<0.0001) and r=-0.59 (p<0.0008), respectively). The correlation of ILD extension in UTE-MRI with FVC and DLCo were significant (-0.68 (p<0.0001) and -0.57 (p<0.002), respectively) too. The UTE-MRI assessments agreed with CT in identifying limited or extensive ILD in 25/29 patients (19 limited and 6 extended) and discordant in 4 (1 limited and 3 extended to CT). UTE-MRI sensitivity and specificity in identifying extended ILD were high (86.4% (65.1% -97.1%) and 85.7% (42.1% -99.6%), respectively). PPV and NPV were 95.0% (75.4% -99.2%) and 66.7% (40.7% -85.7%), respectively.ConclusionUTE-MRI sequence, compared to CT, has shown high correlation with PFR and comparable ability in identifying patients with extensive ILD. Therefore, UTE-MRI seems new promising imaging sequence for the evaluation of ILD extension in SSc patients.References[1]Orlandi M, Landini N, Cerinic MM, Colagrande S. Pulmonary magnetic resonance imaging in systemic sclerosis: a jump in the future to unravel inflammation in interstitial lung disease. Clin Rheumatol. 2021 Sep;40(9):3461-3464. doi: 10.1007/s10067-021-05869-3. Epub 2021 Jul 30. PMID: 34328571.[2]Romei C, Turturici L, Tavanti L, et al. The use of chest magnetic resonance imaging in interstitial lung disease: a systematic review. Eur Respir Rev. 2018;27(150):180062. Doi:10.1183/16000617.0062-2018[3]Pinal-Fernandez I, Pineda-Sanchez V, Pallisa-Nuñez E, et al. Fast 1.5 T chest MRI for the assessment of interstitial lung disease extent secondary to systemic sclerosis. Clin Rheumatol. 2016;35(9):2339-2345. doi:10.1007/s10067-016-3267-0Disclosure of InterestsNone declared

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Ding, Weiwei, Lei Ding, Jinwen Zhu, Li Li, and Feng Ding. "Application of Magnetic Resonance-Ultra Time Echo (MR-UTE) Imaging in the Analysis of the Degree of Degeneration of the Intervertebral Disc Cartilage Endplate." Journal of Medical Imaging and Health Informatics 11, no. 6 (June 1, 2021): 1713–22. http://dx.doi.org/10.1166/jmihi.2021.3711.

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Magnetic resonance imaging (MRI) is the most widely used imaging method in clinical lumbar spine examination. Because of its advantages of non-radiation and good tissue contrast, magnetic resonance imaging provides rich and effective diagnostic information for clinic. The most commonly used sequence is type 2 (T2) sequence, which has a longer time (usually longer than 2000 ms). It shows well in long T2 tissues such as nucleus pulposus, cerebrospinal fluid and adipose tissue, showing moderator high signal in images, while for short T2 tissues such as cartilage endplate and anterior and posterior longitudinal zone, it is often no signal and low signal because of its short attenuation time, thus forming obvious tissue contrast. But at the same time, because the time is too long, for short T2 tissue, the signal has been attenuated to zero before sequence acquisition, so the complete structure can not be displayed directly. In this paper, the normal human lumbar intervertebral disc was studied by conventional magnetic resonance type 1 (T1), T2 and double-echo-UTE imaging techniques. Each part of lumbar intervertebral disc and the semi-quantitative analysis of anatomical structure in images were compared, and the advantages and characteristics of each sequence for each anatomical structure of lumbar intervertebral disc and the advantage of MR-UTE in intervertebral disc display were discussed. It has been found that UTE, as a new sequence which can effectively image short T2 tissue, is gradually applied from experiment to clinic in bone and joint system because of its shorter time. In the gross specimens of lumbar intervertebral disc, sequence can directly display the cartilage endplate and the short T2 tissue of the anterior and posterior longitudinal ligament.

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GLADMAN, DAFNA D. "Group for Research and Assessment of Psoriasis and Psoriatic Arthritis (GRAPPA) 2008." Journal of Rheumatology 37, no. 2 (February 2010): 446–47. http://dx.doi.org/10.3899/jrheum.090954.

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The Group for Research and Assessment of Psoriasis and Psoriatic Arthritis (GRAPPA) is an international group dedicated to improving the lives of patients suffering from psoriasis and psoriatic arthritis (PsA). At the 2008 annual meeting of GRAPPA in Leeds, United Kingdom, members reviewed the status of imaging, including a new ultrasound measure, ultra-short echo time (UTE), and magnetic resonance imaging (MRI) in PsA and the imaging of musculoskeletal tissues in psoriasis; discussed the value and current status of composite measures for the assessment of PsA, including a breakout session where members addressed several issues related to developing PsA-specific composite measures; and reviewed biomarker development in psoriatic disease, including an interactive section on design considerations for a longitudinal study of biomarkers for joint damage. Summaries of those discussions are presented in this supplement.

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Hoerr, Verena, Nina Nagelmann, Arno Nauerth, Michael T. Kuhlmann, Jörg Stypmann, and Cornelius Faber. "Cardiac-respiratory self-gated cine ultra-short echo time (UTE) cardiovascular magnetic resonance for assessment of functional cardiac parameters at high magnetic fields." Journal of Cardiovascular Magnetic Resonance 15, no. 1 (2013): 59. http://dx.doi.org/10.1186/1532-429x-15-59.

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Xu, Pengfei, Jichang Zhang, Zhen Nan, Thomas Meersmann, and Chengbo Wang. "Free-Breathing Phase-Resolved Oxygen-Enhanced Pulmonary MRI Based on 3D Stack-of-Stars UTE Sequence." Sensors 22, no. 9 (April 24, 2022): 3270. http://dx.doi.org/10.3390/s22093270.

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Compared with hyperpolarized noble gas MRI, oxygen-enhanced lung imaging is a cost-effective approach to investigate lung function. In this study, we investigated the feasibility of free-breathing phase-resolved oxygen-enhanced pulmonary MRI based on a 3D stack-of-stars ultra-short echo time (UTE) sequence. We conducted both computer simulation and in vivo experiments and calculated percent signal enhancement maps of four different respiratory phases on four healthy volunteers from the end of expiration to the end of inspiration. The phantom experiment was implemented to verify simulation results. The respiratory phase was segmented based on the extracted respiratory signal and sliding window reconstruction, providing phase-resolved pulmonary MRI. Demons registration algorithm was applied to compensate for respiratory motion. The mean percent signal enhancement of the average phase increases from anterior to posterior region, matching previous literature. More details of pulmonary tissues were observed on post-oxygen inhalation images through the phase-resolved technique. Phase-resolved UTE pulmonary MRI shows the potential as a valuable method for oxygen-enhanced MRI that enables the investigation of lung ventilation on middle states of the respiratory cycle.

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Jang, Hyungseok, Yajun Ma, Michael Carl, Saeed Jerban, Eric Y. Chang, and Jiang Du. "Ultrashort echo time Cones double echo steady state (UTE‐Cones‐DESS) for rapid morphological imaging of short T 2 tissues." Magnetic Resonance in Medicine 86, no. 2 (March 23, 2021): 881–92. http://dx.doi.org/10.1002/mrm.28769.

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Jerban, Saeed, Yajun Ma, Zhao Wei, Hyungseok Jang, Eric Y. Chang, and Jiang Du. "Quantitative Magnetic Resonance Imaging of Cortical and Trabecular Bone." Seminars in Musculoskeletal Radiology 24, no. 04 (August 2020): 386–401. http://dx.doi.org/10.1055/s-0040-1710355.

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AbstractBone is a composite material consisting of mineral, organic matrix, and water. Water in bone can be categorized as bound water (BW), which is bound to bone mineral and organic matrix, or as pore water (PW), which resides in Haversian canals as well as in lacunae and canaliculi. Bone is generally classified into two types: cortical bone and trabecular bone. Cortical bone is much denser than trabecular bone that is surrounded by marrow and fat. Magnetic resonance (MR) imaging has been increasingly used for noninvasive assessment of both cortical bone and trabecular bone. Bone typically appears as a signal void with conventional MR sequences because of its short T2*. Ultrashort echo time (UTE) sequences with echo times 100 to 1,000 times shorter than those of conventional sequences allow direct imaging of BW and PW in bone. This article summarizes several quantitative MR techniques recently developed for bone evaluation. Specifically, we discuss the use of UTE and adiabatic inversion recovery prepared UTE sequences to quantify BW and PW, UTE magnetization transfer sequences to quantify collagen backbone protons, UTE quantitative susceptibility mapping sequences to assess bone mineral, and conventional sequences for high-resolution imaging of PW as well as the evaluation of trabecular bone architecture.

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Lombardi, Alecio F., Yajun Ma, Hyungseok Jang, Saeed Jerban, Qingbo Tang, Adam C. Searleman, Robert Scott Meyer, Jiang Du, and Eric Y. Chang. "AcidoCEST-UTE MRI Reveals an Acidic Microenvironment in Knee Osteoarthritis." International Journal of Molecular Sciences 23, no. 8 (April 18, 2022): 4466. http://dx.doi.org/10.3390/ijms23084466.

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A relationship between an acidic pH in the joints, osteoarthritis (OA), and pain has been previously demonstrated. Acidosis Chemical Exchange Saturation Transfer (acidoCEST) indirectly measures the extracellular pH through the assessment of the exchange of protons between amide groups on iodinated contrast agents and bulk water. It is possible to estimate the extracellular pH in the osteoarthritic joint using acidoCEST MRI. However, conventional MR sequences cannot image deep layers of cartilage, meniscus, ligaments, and other musculoskeletal tissues that present with short echo time and fast signal decay. Ultrashort echo time (UTE) MRI, on the other hand, has been used successfully to image those joint tissues. Here, our goal is to compare the pH measured in the knee joints of volunteers without OA and patients with severe OA using acidoCEST-UTE MRI. Patients without knee OA and patients with severe OA were examined using acidoCEST-UTE MRI and the mean pH of cartilage, meniscus, and fluid was calculated. Additionally, the relationship between the pH measurements and the Knee Injury and Osteoarthritis Outcome Score (KOOS) was investigated. AcidoCEST-UTE MRI can detect significant differences in the pH of knee cartilage, meniscus, and fluid between joints without and with OA, with OA showing lower pH values. In addition, symptoms and knee-joint function become worse at lower pH measurements.

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Krämer, M., M. B. Maggioni, N. M. Brisson, S. Zachow, U. Teichgräber, G. N. Duda, and J. R. Reichenbach. "T1 and T2* mapping of the human quadriceps and patellar tendons using ultra-short echo-time (UTE) imaging and bivariate relaxation parameter-based volumetric visualization." Magnetic Resonance Imaging 63 (November 2019): 29–36. http://dx.doi.org/10.1016/j.mri.2019.07.015.

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Timme, Maximilian, Max Masthoff, Nina Nagelmann, Malte Masthoff, Cornelius Faber, and Sebastian Bürklein. "Imaging of root canal treatment using ultra high field 9.4T UTE-MRI – a preliminary study." Dentomaxillofacial Radiology 49, no. 1 (January 2020): 20190183. http://dx.doi.org/10.1259/dmfr.20190183.

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Objectives: To investigate the potential of 9.4T ultrashort echo time (UTE) technology visualizing tooth anatomy and root canal treatment in vitro. In particular, it was evaluated whether the currently achievable resolution is suited presenting all anatomical structures and whether the root canal filling materials are distinguishable in UTE-MRI. Methods: Four extracted human teeth were examined using 9.4T UTE-MRI prior endodontic treatment (native teeth), after preparation and after obturation procedure. Root canal obturation was performed using warm vertical compaction (Schilder technique) with an epoxy-resin-based sealer. A single gutta-percha cone measured by MRI served as intensity-reference. MRI results were validated with corresponding histologic sections of the teeth. In addition, all teeth were examined at the different stages with CBCT and conventional X-ray. Results: 9.4T UTE-MRI enabled a precise visualization of root canal anatomy of all teeth at a resolution of 66 µm. After obturation, dentin, sealer and gutta-percha cones showed distinct MRI signal changes that allowed clear differentiation of the obturation materials from surrounding tooth structure. The filling materials, isthmal root canal connections and even dentin-cracks that were identified in the MR-images could be verified in histological sections. Conclusions: 9.4T UTE-MRI is suitable for visualization of root canal anatomy, the evaluation of root canal preparation and obturation with a high spatial resolution and may provide a versatile tool for dental material research in endodontics.

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Bydder, Mark, Richard Znamirowski, and Graeme Bydder. "Magnetic Resonance Imaging of Short T2 Relaxation Components in Tissue Using Ultrashort Echo Time (UTE) Pulse Sequences." Current Medical Imaging Reviews 2, no. 1 (February 1, 2006): 79–90. http://dx.doi.org/10.2174/157340506775541640.

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Du, Jiang, Atsushi M. Takahashi, Won C. Bae, Christine B. Chung, and Graeme M. Bydder. "Dual inversion recovery, ultrashort echo time (DIR UTE) imaging: Creating high contrast for short-T 2 species." Magnetic Resonance in Medicine 63, no. 2 (January 23, 2010): 447–55. http://dx.doi.org/10.1002/mrm.22257.

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Warth, Ryan J., Payam Zandiyeh, Mayank Rao, Refaat E. Gabr, Scott Tashman, Manickam Kumaravel, Ponnada A. Narayana, Walter R. Lowe, and Christopher D. Harner. "Quantitative Assessment of In Vivo Human Anterior Cruciate Ligament Autograft Remodeling: A 3-Dimensional UTE-T2* Imaging Study." American Journal of Sports Medicine 48, no. 12 (September 11, 2020): 2939–47. http://dx.doi.org/10.1177/0363546520949855.

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Background: The timing of return to play after anterior cruciate ligament (ACL) reconstruction is still controversial due to uncertainty of true ACL graft state at the time of RTP. Recent work utilizing ultra-short echo T2* (UTE-T2*) magnetic resonance imaging (MRI) as a scanner-independent method to objectively and non-invasively assess the status of in vivo ACL graft remodeling has produced promising results. Purpose/Hypothesis: The purpose of this study was to prospectively and noninvasively investigate longitudinal changes in T2* within ACL autografts at incremental time points up to 12 months after primary ACL reconstruction in human patients. We hypothesized that (1) T2* would increase from baseline and initially exceed that of the intact contralateral ACL, followed by a gradual decline as the graft undergoes remodeling, and (2) remodeling would occur in a region-dependent manner. Study Design: Case series; Level of evidence, 4. Methods: Twelve patients (age range, 14-45 years) who underwent primary ACL reconstruction with semitendinosus tendon or bone–patellar tendon–bone autograft (with or without meniscal repair) were enrolled. Patients with a history of previous injury or surgery to either knee were excluded. Patients returned for UTE MRI at 1, 3, 6, 9, and 12 months after ACL reconstruction. Imaging at 1 month included the contralateral knee. MRI pulse sequences included high-resolution 3-dimensional gradient echo sequence and a 4-echo T2-UTE sequence (slice thickness, 1 mm; repetition time, 20 ms; echo time, 0.3, 3.3, 6.3, and 9.3 ms). All slices containing the intra-articular ACL were segmented from high-resolution sequences to generate volumetric regions of interest (ROIs). ROIs were divided into proximal/distal and core/peripheral sub-ROIs using standardized methods, followed by voxel-to-voxel registration to generate T2* maps at each time point. This process was repeated by a second reviewer for interobserver reliability. Statistical differences in mean T2* values and mean ratios of T2*inj/T2*intact (ie, injured knee to intact knee) among the ROIs and sub-ROIs were assessed using repeated measures and one-way analyses of variance. P < .05 represented statistical significance. Results: Twelve patients enrolled in this prospective study, 2 withdrew, and ultimately 10 patients were included in the analysis (n = 7, semitendinosus tendon; n = 3, bone–patellar tendon–bone). Interobserver reliability for T2* values was good to excellent (intraclass correlation coefficient, 0.84; 95% CI, 0.59-0.94; P < .001). T2* values increased from 5.5 ± 2.1 ms (mean ± SD) at 1 month to 10.0 ± 2.9 ms at 6 months ( P = .001), followed by a decline to 8.1 ± 2.0 ms at 12 months ( P = .129, vs 1 month; P = .094, vs 6 months). Similarly, mean T2*inj/T2*intact ratios increased from 62.8% ± 22.9% at 1 month to 111.1% ± 23.9% at 6 months ( P = .001), followed by a decline to 92.8% ± 29.8% at 12 months ( P = .110, vs 1 month; P = .086, vs 6 months). Sub-ROIs exhibited similar increases in T2* until reaching a peak at 6 months, followed by a gradual decline until the 12-month time point. There were no statistically significant differences among the sub-ROIs ( P > .05). Conclusion: In this preliminary study, T2* values for ACL autografts exhibited a statistically significant increase of 82% between 1 and 6 months, followed by an approximate 19% decline in T2* values between 6 and 12 months. In the future, UTE-T2* MRI may provide unique insights into the condition of remodeling ACL grafts and may improve our ability to noninvasively assess graft maturity before return to play.

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COATES, LAURA C., DENNIS M. McGONAGLE, RICHARD HODGSON, PAOLO GISONDI, ARTHUR F. KAVANAUGH, ABRAR A. QURESHI, OLIVER FITZGERALD, et al. "Imaging in Psoriasis and Psoriatic Arthritis: GRAPPA 2008." Journal of Rheumatology 37, no. 2 (February 2010): 448–52. http://dx.doi.org/10.3899/jrheum.090955.

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At the 2008 meeting of GRAPPA (Group for Research and Assessment of Psoriasis and Psoriatic Arthritis), the primary focus of the imaging session was the enthesis. Presentations from Dennis McGonagle (Leeds, UK), Richard Hodgson (Leeds, UK), and Paolo Gisondi (Verona, Italy) elaborated on this theme and prepared the meeting attendees for group discussions of further work in this area. Imaging, notably magnetic resonance imaging (MRI) and ultrasonography, provides evidence of pathological change at the enthesis in psoriatic arthritis (PsA). Further, imaging abnormalities are found at sites that are asymptomatic in both PsA and psoriasis. The role of newer imaging modalities, such as ultra-short echo time (UTE) MRI, is promising but remains to be fully elucidated. The implication of these findings in relation to subclinical and predisease status is intriguing and requires further study in longitudinal studies. Further work is also required to examine the proposed common biomechanical basis between joint and skin, the mechanism of the resulting inflammation, and how these mechanisms differ from those seen in rheumatoid arthritis.

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Roche, D., C. Michel, P. Daudé, A. Le Troter, C. Chagnaud, J. P. Mattei, L. Pini, M. Guye, D. Bendahan, and S. Guis. "AB1098 STRUCTURAL ELEMENTS OF THE KNEE ENTHESES ASSESSED IN HEALTHY SUBJECTS WITH ULTRA HIGH FIELD MRI (150 MICRONS)." Annals of the Rheumatic Diseases 79, Suppl 1 (June 2020): 1838. http://dx.doi.org/10.1136/annrheumdis-2020-eular.1191.

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Background:Fibrocartilaginous enthesis is composed of different histological zones which are commonly referred to the tendon distal extremity (a lamellar tissue with a low cell density, collagen and connective tissue), the fibrocartilaginous zone (with chondrocytes), a progressively mineralized zone and the bone. The MRI visualization of the water content of entheses is challenging given the very short relation time so that entheses has been very poorly assessed using MRI (1).Objectives:The main objective of the study was to assess the structural elements of the knee enthesis based on the quantitative T2* measurements using Ultra High Field (UHF) MRI.Methods:Twelve healthy subjects without any osteoarticular pathology were included in the study after they provided their informed consent. 3D gradient echo sequence with a 4.3 ms echo time and T2* mapping were performed. The lateral internal, external and crossed ligaments, patellar and quadricipital tendons were assessed. T2* measurements were performed specifically on the quadricipital tendon.Results:The quadricipital tendon and the bone trabeculation could be visualized on the UHF MR image. The T2* mapping analysis illustrated a large value (16.4 ± 4 ms) for the subchondral bone and much lower values for the trabecular bone (11 ± 4.5 ms) and the different zones of the keen entheses (7.7 ± 1.9 ms).Conclusion:Based on T2* measurements performed using UHF MRI, the different structural elements of the knee entheses were distinguished. This quantitative stratification could be used to assess changes in pathological conditions such as SpA and trauma.References:[1]Benjamin M, Bydder GM. Magnetic resonance imaging of entheses using ultrashort TE (UTE) pulse sequences. Journal of magnetic resonance imaging: JMRI. 2007;25(2):381-9.Disclosure of Interests:None declared

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Lee, Young Han, Sungjun Kim, Ho-Taek Song, InSeong Kim, and Jin-Suck Suh. "Weighted subtraction in 3D ultrashort echo time (UTE) imaging for visualization of short T2 tissues of the knee." Acta Radiologica 55, no. 4 (May 2014): 454–61. http://dx.doi.org/10.1177/0284185113496994.

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Liu, Jin, Amin Nazaran, Yajun Ma, Haimei Chen, Yanchun Zhu, Jiang Du, Shaolin Li, Quan Zhou, and Yinghua Zhao. "Single- and Bicomponent Analyses of T2⁎ Relaxation in Knee Tendon and Ligament by Using 3D Ultrashort Echo Time Cones (UTE Cones) Magnetic Resonance Imaging." BioMed Research International 2019 (February 18, 2019): 1–9. http://dx.doi.org/10.1155/2019/8597423.

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The collagen density is not detected in the patellar tendon (PT), posterior cruciate ligament (PCL), and anterior cruciate ligament (ACL) in clinic. We assess the technical feasibility of three-dimension multiecho fat saturated ultrashort echo time cones (3D FS-UTE-Cones) acquisitions for single- and bicomponent T2⁎ analysis of bound and free water pools in PT, PCL, and ACL in clinic. The knees of five healthy volunteers and six knee joint samples from cadavers were scanned via 3D multiecho FS-UTE-Cones acquisitions on a clinical scanner. Single-component fitting of T2⁎M and bicomponent fitting of short T2⁎ (T2⁎S), long T2⁎ (T2⁎L), short T2⁎ fraction (Frac_S), and long T2⁎ fraction (Frac_L) were performed within tendons and ligaments. Our results showed that biexponential fitting was superior to single-exponential fitting in PT, PCL, and ACL. For knee joint samples, there was no statistical difference among all data in PT, PCL, and ACL. For volunteers, all parameters of bicomponent fitting were statistically different across PT, PCL, and ACL, except for T2⁎S, T2⁎L, and T2⁎M resulting in flawed measurements due to the magic angle effect. 3D multiecho FS-UTE-Cones acquisition allows high resolution T2⁎ mapping in PT, PCL, and ACL of keen joint samples and PT and PCL of volunteers. The T2⁎ values and their fractions can be characterized by bicomponent T2⁎ analysis that is superior to single-component T2⁎ analysis, except for ACL of volunteers.

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Zandiyeh, Payam, Mayank Rao, Refaat Gabr, Ponnada Narayana, Scott Tashman, Manickam Kumaravel, Walter Lowe, Christopher Harner, and Ryan Warth. "Three-Dimensional UTE MR Imaging: Twelve-Month Analysis of ACL Autograft Remodeling." Orthopaedic Journal of Sports Medicine 8, no. 7_suppl6 (July 1, 2020): 2325967120S0047. http://dx.doi.org/10.1177/2325967120s00479.

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Objectives: Post-reconstruction imaging of the anterior cruciate ligament (ACL) is needed to non-invasively assess in vivo graft maturity before release to play. The purpose of this study was to evaluate autograft remodeling up to 12 months after ACL reconstruction using 3D ultra-short time to echo (UTE) T2* MRI. We hypothesized that the T2* values of ACL autografts would progressively change over time, initially resembling the values for the native contralateral graft source and gradually approaching that of the intact contralateral ACL. Methods: After IRB approval, 12 patients (ages 14-45 years) who underwent primary ACL reconstruction (ACLR) with semitendinosus (SemiT) or bone-patellar tendon-bone (BTB) autograft were enrolled. Patients with a history of prior injury or surgery to either knee were excluded. Subjects returned for UTE MRIs at 1, 3, 6, 9, and 12 months after ACLR. Imaging at 1-month included the contralateral knee. All scans were performed on a Philips Ingenia 3T system. MRI pulse sequences included high-resolution 3D T2 (slice thickness: 0.6mm, TR: 18.7ms; TE: 11.5ms) and a four-echo T2 UTE (slice thickness: 1mm, TR: 20ms; TE: 0.3, 3.3, 6.3, and 9.3ms). Using high-resolution 3D T2 sequences at 1 month, all slices containing the intra-articular ACL were segmented semi-automatically to generate volumetric regions of interest (ROIs) (Materialise, Inc.; Leuven, Belgium). ROIs were divided into proximal/distal and core/peripheral sub-ROIs using standardized methods. Each ROI was co-registered voxel-by-voxel to T2* maps also obtained at 1 month. These T2* maps were then co-registered with those of subsequent time points. The segmentation process was repeated for the 1-, 3-, and 6-month time points by a second reviewer for inter-observer reliability (κ). Statistical differences among the ROIs and sub-ROIs of ACL autografts were assessed with repeated-measures ANOVA and two-tailed non-parametric t-tests. P<0.05 represented statistical significance. Results: Twelve subjects were enrolled in this prospective study, and after 2 subjects withdrew, 10 subjects were included in the analysis (n=7 SemiT; n=3 BTB). Nine of 10 subjects attended all postoperative imaging sessions at the time of this writing. Inter-observer reliability for T2* values was found to be excellent (κ=0.832; 95% CI [0.70-0.91]; p<0.001). Average T2* relaxation times increased from 3.2ms (standard deviation [SD], 1.0) at 1 month, to 4.8ms (SD, 1.8) at 6 months, and 4.1ms (SD, 1.6) at 12 months (Figures 1 and 2), with statistically significant differences between the intact ACL and 1-month time point (p=0.01), and between the 1- and 6-month time points (p=0.004). The ratio of T2*[inj]/T2*[intact] increased from 59.2% at 1 month to 79.8% at 12 months for SemiT autografts, and from 86.9% at 1 month to 97.2% at 12 months for BTB autografts (p=0.001). Significant differences were found between the following pairs of sub-ROIs when combining all time points: proximal/distal, proximal-peripheral/proximal-core, distal-peripheral/distal-core (p<0.02 each). Conclusions: ACL autografts exhibited progressively increasing T2* values and T2*[inj]/T2*[intact] ratios up to 12 months after ACLR, and these changes appear to be region-dependent. UTE T2* MR imaging can provide unique insights into the condition of remodeling ACL grafts, and may improve our ability to non-invasively assess graft maturity before allowing patients to resume high-intensity activities.

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Landini, N., M. Orlandi, M. Occhipinti, C. Nardi, L. Tofani, S. Bellando-Randone, C. Bruni, M. Matucci-Cerinic, G. Morana, and S. Colagrande. "POS0264 THE EMERGING ROLE OF MAGNETIC RESONANCE IMAGING IN INTERSTITIAL LUNG DISEASE IN SYSTEMIC SCLEROSIS: EVIDENCE FOR ULTRA SHORT TE AND COMPRESSED SENSING VIBE ACQUISITIONS AS PROMISING TOOLS FOR THE EVALUATION OF PARENCHYMAL ALTERATIONS." Annals of the Rheumatic Diseases 80, Suppl 1 (May 19, 2021): 355.1–355. http://dx.doi.org/10.1136/annrheumdis-2021-eular.3253.

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Background:Interstitial lung disease (ILD) is a frequent complication and the major cause of death in Systemic sclerosis (SSc). Computed tomography (CT) is the gold standard imaging technique to assess ILD but is burdened by exposure to ionizing radiations that limits its use for the follow-up. MRI sequences with Ultra Short Echo Time (UTE) are promising for ILD.Objectives:We tested two MRI sequences, UTE Spiral VIBE and Compressing Sensing (CS) VIBE, in SSc-ILD, in comparison to chest CT.Methods:SSc patients with suspected-ascertained ILD were evaluated for undergoing CT-MRI examinations in the same day. Two radiologists visually scored the extent of ground glass opacities (GGO), reticulations, honeycombing and consolidations on CT-MRI. The sum of alteration was assumed as ILD extent. A quantitative texture analysis (qCT) was also performed on CT. Cohen’s k was adopted for interreader concordance in ILD detection. MRI sensitivity and specificity in ILD detection were evaluated. Lin’s concordance was adopted to compare extent analysis between readers and between CT (visual and qCT analysis) and MRI sequences.Results:54 patients performed both CT and MRI. MRI interreader concordance was moderate in ILD detection, while ILD and GGO extent analysis showed good or very good concordance. UTE Spiral VIBE had a sensitivity and specificity in ILD detection of 95.8% and 77.8%, while alterations extent analysis obtained a very good concordance with CT for ILD and GGO. CS VIBE showed a sensitivity and specificity in ILD detection of 46.7% and 95.0%, but a slight or fair concordance with CT in all alterations’ extent analysis.Conclusion:MRI UTE Spiral VIBE sequences are helpful in the evaluation of SSc-ILD. Larger cohorts of patients will be needed to confirm that MRI may be useful in clinical practice, reducing the radiological load of chest CTReferences:[1]Romei C, Turturici L, Tavanti L, et al. The use of chest magnetic resonance imaging in interstitial lung disease: a systematic review. Eur Respir Rev. 2018;27(150):180062. Doi:10.1183/16000617.0062-2018[2]Miller GW, Mugler JP, Sá RC, Altes TA, Prisk GK, Hopkins SR. Advances in functional and structural imaging of the human lung using proton MRI. NMR Biomed. 2014;27(12):1542-1556. doi:10.1002/nbm.3156[3]Pinal-Fernandez I, Pineda-Sanchez V, Pallisa-Nuñez E, et al. Fast 1.5 T chest MRI for the assessment of interstitial lung disease extent secondary to systemic sclerosis. Clin Rheumatol. 2016;35(9):2339-2345. doi:10.1007/s10067-016-3267-0[4]Ohno Y, Koyama H, Yoshikawa T, et al. Pulmonary high-resolution ultrashort TE MR imaging: Comparison with thin-section standard- and low-dose computed tomography for the assessment of pulmonary parenchyma diseases: Pulmonary MRI with UTE in Pulmonary Disease. J Magn Reson Imaging. 2016;43(2):512-532. doi:10.1002/jmri.25008Disclosure of Interests:None declared

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Ma, Ya-Jun, Hyungseok Jang, Zhao Wei, Zhenyu Cai, Yanping Xue, Roland R. Lee, Eric Y. Chang, Graeme M. Bydder, Jody Corey-Bloom, and Jiang Du. "Myelin Imaging in Human Brain Using a Short Repetition Time Adiabatic Inversion Recovery Prepared Ultrashort Echo Time (STAIR-UTE) MRI Sequence in Multiple Sclerosis." Radiology 297, no. 2 (November 2020): 392–404. http://dx.doi.org/10.1148/radiol.2020200425.

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Mastrogiacomo, Simone, Weiqiang Dou, John A. Jansen, and X. Frank Walboomers. "Magnetic Resonance Imaging of Hard Tissues and Hard Tissue Engineered Bio-substitutes." Molecular Imaging and Biology 21, no. 6 (November 7, 2019): 1003–19. http://dx.doi.org/10.1007/s11307-019-01345-2.

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Abstract Magnetic resonance imaging (MRI) is a non-invasive diagnostic imaging tool based on the detection of protons into the tissues. This imaging technique is remarkable because of high spatial resolution, strong soft tissue contrast and specificity, and good depth penetration. However, MR imaging of hard tissues, such as bone and teeth, remains challenging due to low proton content in such tissues as well as to very short transverse relaxation times (T2). To overcome these issues, new MRI techniques, such as sweep imaging with Fourier transformation (SWIFT), ultrashort echo time (UTE) imaging, and zero echo time (ZTE) imaging, have been developed for hard tissues imaging with promising results reported. Within this article, MRI techniques developed for the detection of hard tissues, such as bone and dental tissues, have been reviewed. The main goal was thus to give a comprehensive overview on the corresponding (pre-) clinical applications and on the potential future directions with such techniques applied. In addition, a section dedicated to MR imaging of novel biomaterials developed for hard tissue applications was given as well.

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Ma, Ya‐Jun, Yanchun Zhu, Xing Lu, Michael Carl, Eric Y. Chang, and Jiang Du. "Short T 2 imaging using a 3D double adiabatic inversion recovery prepared ultrashort echo time cones (3D DIR‐UTE‐Cones) sequence." Magnetic Resonance in Medicine 79, no. 5 (September 14, 2017): 2555–63. http://dx.doi.org/10.1002/mrm.26908.

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Anderson, C., and C. Flask. "ID: 63: RAPID 3D PRECLINICAL QUANTITATIVE LUNG IMAGING WITH ULTRASHORT-ECHO TIME (UTE) MRI IN A MOUSE MODEL OF CYSTIC FIBROSIS LUNG DISEASE." Journal of Investigative Medicine 64, no. 4 (March 22, 2016): 975.1–975. http://dx.doi.org/10.1136/jim-2016-000120.133.

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Currently, the life expectancy for cystic fibrosis (CF) lung disease is less than 40 years due to decreasing lung function despite significant advances in the care and treatment of these patients. As patients live longer, the preservation of healthy lung tissue becomes of paramount importance to improve patient quality of life and increase life span. To do this, an understanding of the early disease processes is needed as is an ability to monitor the efficacy of therapeutic interventions early in life. CF lung disease, similar to other lung diseases, is a regional disease causing local dysfunction in the lung tissue and changes in lung anatomy. It is important for any monitoring or diagnostic tool to be sensitive to early regional disease which current methods (spirometry) are not. This lack of sensitivity to regional disease limits the ability of physicians and researchers to track the earliest stages of disease and assess treatment efficacy in these initial disease stages, ideally in infants and young children. Three dimensional imaging presents a unique solution to this problem by providing a non-invasive, volumetric investigation of the lung tissue. Computed tomography has long been the first choice in clinical lung imaging offering excellent resolution and fast imaging times but results in repeated exposure to ionizing radiation. Because the patient populations of interest are infants and children, avoidance of unnecessary, repeated radiation exposure during longitudinal monitoring is desirable. This combination of clinical and research need has led us to the exploration of rapid MRI techniques for lung imaging. We are interested in developing a novel, robust quantitative Magnetic Resonance Imaging technique that allows for 3D investigation of the lung tissue and is sensitive to early disease changes. Our hypothesis is that quantitative imaging will be able to detect changes in regional lung anatomy as an indication of early disease before disease is detected by standard methods. To accomplish this goal, we are proposing the implementation of multiple advanced quantitative MRI techniques including T1-mapping using Saturation-Recovery Look-Locker mapping and simultaneous multiple parameter mapping (combinations of T1, T2, T2*) using the recently developed Magnetic Resonance Fingerprinting method. An ultra-short echo time acquisition will be used to ensure imaging of the rapidly decaying MRI signal in the lung is possible. Using a radial acquisition, we plan to include an undersampled acquisition to reduce imaging time and generate an imaging method that is rapid and insensitive to patient motion. Our goal is to initially apply these quantitative measures in a mouse model of cystic fibrosis to establish the ability of the imaging methods to be sensitive to regional disease in CF mice. We expect to see changes in the quantitative parameters in areas that correspond to diseased areas of the lung upon histological investigation. These quantitative measurements should give unambiguous indications of disease and allow identification of changes in lung anatomy early in the disease process. This work will lay the foundation for translation of clinical CF monitoring in a pediatric population. Translational studies such as these will hopefully provide a measurement of disease progression and provide a new opportunity to evaluate early disease therapeutics offering insight into the earliest manifestations of CF lung disease.

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Malmgaard-Clausen, Nikolaj M., Oscar H. Jørgensen, Rikke Høffner, Peter E. B. Andersen, Rene B. Svensson, Philip Hansen, Janus D. Nybing, S. Peter Magnusson, and Michael Kjær. "No Additive Clinical or Physiological Effects of Short-term Anti-inflammatory Treatment to Physical Rehabilitation in the Early Phase of Human Achilles Tendinopathy: A Randomized Controlled Trial." American Journal of Sports Medicine 49, no. 7 (March 15, 2021): 1711–20. http://dx.doi.org/10.1177/0363546521991903.

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Background: Nonsteroidal anti-inflammatory drugs (NSAIDs) are commonly used in the treatment of Achilles tendinopathy, but whether they have any additive clinical effect on physical rehabilitation in the early phase of tendinopathy remains unknown. Purpose/Hypothesis: To investigate whether an initial short-term NSAID treatment added to a physical rehabilitation program in the early phase of Achilles tendinopathy would have an additive effect. We hypothesized that the combination of NSAID and rehabilitation would be superior to rehabilitation alone. Study Design: Randomized controlled trial; Level of evidence, 1. Methods: A total of 69 patients with early phase Achilles tendinopathy (lasting <3 months) were randomly assigned to either a naproxen group (7 days of treatment; 500 mg twice daily; n = 34) or a placebo group (7 days of placebo treatment; n = 35). Both groups received an identical 12-week physical rehabilitation program. The clinical outcome of the study was evaluated using the Victorian Institute of Sports Assessment–Achilles (VISA-A) questionnaire and a numerical rating scale (NRS), and the physiological outcome was evaluated using ultrasonography, magnetic resonance imaging (MRI), and ultra-short time to echo T2* mapping MRI (UTE T2* MRI). Follow-up was performed at 1 week, 3 months, and 1 year. Time effects are presented as mean difference ± SEM. Results: No significant differences were found between the 2 treatment groups for any of the outcome measures at any time point ( P > .05). For the VISA-A score, a significant time effect was observed between baseline and 3-month follow-up (14.9 ± 2.3; P < .0001), and at 1-year follow-up, additional improvements were observed (6.1 ± 2.3; P < .01). Furthermore, the change in VISA-A score between baseline and 3-month follow-up was greater in patients with very short symptom duration (<1 month) at baseline compared with patients who had longer symptom duration (>2 months) (interaction between groups, 11.7 ± 4.2; P < .01). Despite clinical improvements, total weekly physical activity remained lower compared with preinjury levels at 3 months (–2.7 ± 0.5 h/wk; P < .0001) and 1 year (–3.0 ± 0.5 h/wk; P < .0001). At baseline, ultrasonography showed increased thickness (0.12 ± 0.03 cm; P < .0001) and vascularity (0.3 ± 0.1 cm2; P < .005) on the tendinopathic side compared with the contralateral side, but no changes over time were observed for ultrasonography, MRI, or UTE T2* MRI results. Conclusion: Clinical symptoms in early tendinopathy improved with physical rehabilitation, but this improvement was not augmented with the addition of NSAID treatment. Furthermore, this clinical recovery occurred in the absence of any measurable structural alterations. Finally, clinical improvements after a physical rehabilitation program were greater in patients with very short symptom duration compared with patients who had longer symptom duration. Registration: NCT03401177 (ClinicalTrials.gov identifier) and BFH-2016-019 (Danish Data Protection Agency)

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Ma, Ya-Jun, Xing Lu, Michael Carl, Yanchun Zhu, Nikolaus M. Szeverenyi, Graeme M. Bydder, Eric Y. Chang, and Jiang Du. "Accurate T1mapping of short T2tissues using a three-dimensional ultrashort echo time cones actual flip angle imaging-variable repetition time (3D UTE-Cones AFI-VTR) method." Magnetic Resonance in Medicine 80, no. 2 (January 3, 2018): 598–608. http://dx.doi.org/10.1002/mrm.27066.

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Faas, Henryk M., James L. Krupa, Alexander J. Taylor, Francesco Zamberlan, Christopher J. Philp, Huw E. L. Williams, Simon R. Johnson, Galina E. Pavlovskaya, Neil R. Thomas, and Thomas Meersmann. "Accelerated 19F·MRI Detection of Matrix Metalloproteinase-2/-9 through Responsive Deactivation of Paramagnetic Relaxation Enhancement." Contrast Media & Molecular Imaging 2019 (February 28, 2019): 1–13. http://dx.doi.org/10.1155/2019/4826520.

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Paramagnetic gadolinium ions (GdIII), complexed within DOTA-based chelates, have become useful tools to increase the magnetic resonance imaging (MRI) contrast in tissues of interest. Recently, “on/off” probes serving as 19F·MRI biosensors for target enzymes have emerged that utilize the increase in transverse (T2∗ or T2) relaxation times upon cleavage of the paramagnetic GdIII centre. Molecular 19F·MRI has the advantage of high specificity due to the lack of background signal but suffers from low signal intensity that leads to low spatial resolution and long recording times. In this work, an “on/off” probe concept is introduced that utilizes responsive deactivation of paramagnetic relaxation enhancement (PRE) to generate 19F longitudinal (T1) relaxation contrast for accelerated molecular MRI. The probe concept is applied to matrix metalloproteinases (MMPs), a class of enzymes linked with many inflammatory diseases and cancer that modify bioactive extracellular substrates. The presence of these biomarkers in extracellular space makes MMPs an accessible target for responsive PRE deactivation probes. Responsive PRE deactivation in a 19F biosensor probe, selective for MMP-2 and MMP-9, is shown to enable molecular MRI contrast at significantly reduced experimental times compared to previous methods. PRE deactivation was caused by MMP through cleavage of a protease substrate that served as a linker between the fluorine-containing moiety and a paramagnetic GdIII-bound DOTA complex. Ultrashort echo time (UTE) MRI and, alternatively, short echo times in standard gradient echo (GE) MRI were employed to cope with the fast 19F transverse relaxation of the PRE active probe in its “on-state.” Upon responsive PRE deactivation, the 19F·MRI signal from the “off-state” probe diminished, thereby indicating the presence of the target enzyme through the associated negative MRI contrast. Null point 1H·MRI, obtainable within a short time course, was employed to identify false-positive 19F·MRI responses caused by dilution of the contrast agent.

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Du, Jiang, Guolin Ma, Shihong Li, Michael Carl, Nikolaus M. Szeverenyi, Scott VandenBerg, Jody Corey-Bloom, and Graeme M. Bydder. "Ultrashort echo time (UTE) magnetic resonance imaging of the short T2 components in white matter of the brain using a clinical 3T scanner." NeuroImage 87 (February 2014): 32–41. http://dx.doi.org/10.1016/j.neuroimage.2013.10.053.

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Wei, Zhao, Ya-Jun Ma, Hyungseok Jang, Wenhui Yang, and Jiang Du. "To measure T1 of short T2 species using an inversion recovery prepared three-dimensional ultrashort echo time (3D IR-UTE) method: A phantom study." Journal of Magnetic Resonance 314 (May 2020): 106725. http://dx.doi.org/10.1016/j.jmr.2020.106725.

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Kennan, Richard P., Dawn Alleyne, Thomas K. Aldrich, Sandra M. Suzuka, Robert Renick, Ronald L. Nagel, and Mary E. Fabry. "Detection of Acute Chest Syndrome by MRI in a Sickle Transgenic Mouse Model." Blood 104, no. 11 (November 16, 2004): 3749. http://dx.doi.org/10.1182/blood.v104.11.3749.3749.

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Abstract Acute chest syndrome (ACS) is a potentially deadly complication in sickle cell patients, particularly in young adults. In patients younger than 17 years, ACS is frequently associated with infection; however, in adults, association with vasocclusive crisis and fat and bone marrow embolism is more common. We have developed a sickle transgenic mouse model for ACS that consists of injecting a mixture of bone marrow and mouse fat into the tail vein of a sickle transgenic mouse. The mouse used was a NY1 partial KO that expresses 100% human α and 55% βS. Mice were injected with bone marrow (BM) from two femurs (about 15 mg) and, as murine BM lacks fat, purified peritoneal fat (about 15 mg). Creatine kinase (CK), predominantly the MM form, and sVCAM increased above baseline levels at 6, 24, and 48 hours in NY1 partial KO mice, but not in control C57Bl mice. Magnetic resonance imaging (MRI) was performed at 48 hours after the initial injection. It is normally difficult to perform MR imaging of lung due to its inherently short transverse relaxation time and relatively low proton density relative to other tissue. However, these difficulties can be overcome through the use of ultra short echo time spin echo sequences at high field strength. Spin echo images were obtained using a respiratory-gated spin echo sequences at TE=3 msec and at TE=10 msec. From this data one can calculate a quantitative relaxation rate (1/T2) map and an average value of R2. Decreased values for mean R2 are an indication of fluid accumulation. In NY1 partial KO mice examined 48 hours after injection, the 1/T2 map revealed focal patches with high water content and a mean R2 of 131 vs R2 = 220 for an uninjected control mouse; when the same animals were examined three months later R2s were found to be 181 and 124. C57Bl control mice were also examined at 48 hours post injection, and R2 values of 211 and 178 were found. Pulmonary edema is a defining finding in ACS and its presence in sickle mice, but not in control mice is strong support for this model. The mice survived both the fat/BM injection and the MRI, indicating that it will be possible to obtain repeated images from the same animal to study the natural course of lung injury and interventions that may ameliorate injury.

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Chu, Constance R., and Ashley A. Williams. "Quantitative MRI UTE-T2* and T2* Show Progressive and Continued Graft Maturation Over 2 Years in Human Patients After Anterior Cruciate Ligament Reconstruction." Orthopaedic Journal of Sports Medicine 7, no. 8 (August 2019): 232596711986305. http://dx.doi.org/10.1177/2325967119863056.

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Background: Noninvasive quantitative magnetic resonance imaging (MRI) measures to assess anterior cruciate ligament (ACL) graft maturity are needed to help inform return to high-demand activities and to evaluate the effectiveness of new treatments to accelerate ACL graft maturation. Quantitative MRI ultrashort echo time T2* (UTE-T2*) and T2* mapping captures short T2 signals arising from collagen-associated water in dense regular connective tissues, such as tendon, ligament, and maturing grafts, which are invisible to conventional MRI. Hypothesis: Quantitative MRI UTE-T2* and T2* mapping is sensitive to ACL graft changes over the first 2 years after ACL reconstruction (ACLR). Study Design: Case series; Level of evidence, 4. Methods: A total of 32 patients (18 men; mean ± SD age, 30 ± 9 years) undergoing unilateral ACLR and 30 uninjured age-matched controls (18 men; age, 30 ± 9 years) underwent 3-T MRI examination. Patients who underwent ACLR were imaged at 6 weeks, 6 months, and 1 and 2 years postoperatively. Two separate ACLR cohorts were scanned with 2 MRI platforms at 2 institutions. Twelve ACLR knees were scanned with a 3-dimensional acquisition-weighted stack of spirals UTE sequence on a Siemens scanner, and 20 ACLR knees were scanned with a 3-dimensional Cones UTE sequence on a GE scanner. UTE-T2* or T2* maps were calculated for the intra-articular portion of the ACL graft. Results: Mean ACL graft UTE-T2* and T2* decreased from 1 to 2 years after ACLR. ACL graft T2* increased 25% to 30% during the first 6 months ( P < .013) to a level not different from that of uninjured native ACL ( P > .4), stabilized between 6 months and 1 year ( P ≥ .999), and then decreased 19% between 1 and 2 years after ACLR ( P = .027). At 6-month follow-up, ACL graft UTE-T2* differed from that of tendon ( P < .02) but not uninjured native ACL ( P > .7) and showed the greatest variability among patients. Conclusion: UTE-T2* mapping suggested substantial changes within the graft during the first 6 months postsurgery. T2* and UTE-T2* mapping showed relatively stable graft composition from 6 months to 1 year, consistent with remodeling, followed by decreases from 1 to 2 years, suggestive of continuing maturation. MRI UTE-T2* and T2* mapping demonstrated potential clinical utility as noninvasive quantitative imaging metrics for evaluation of human ACL grafts.

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Romei, Chiara, Laura Turturici, Laura Tavanti, Jelle Miedema, Sara Fiorini, Massimo Marletta, Piotr Wielopolski, Harm Tiddens, Fabio Falaschi, and Pierluigi Ciet. "The use of chest magnetic resonance imaging in interstitial lung disease: a systematic review." European Respiratory Review 27, no. 150 (December 19, 2018): 180062. http://dx.doi.org/10.1183/16000617.0062-2018.

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Thin-slices multi-detector computed tomography (MDCT) plays a key role in the differential diagnosis of interstitial lung disease (ILD). However, thin-slices MDCT has a limited ability to detect active inflammation, which is an important target of newly developed ILD drug therapy. Magnetic resonance imaging (MRI), thanks to its multi-parameter capability, provides better tissue characterisation than thin-slices MDCT.Our aim was to summarise the current status of MRI applications in ILD and to propose an ILD-MRI protocol. A systematic literature search was conducted for relevant studies on chest MRI in patients with ILD.We retrieved 1246 papers of which 55 original papers were selected for the review. We identified 24 studies comparing image quality of thin-slices MDCT and MRI using several MRI sequences. These studies described new MRI sequences to assess ILD parenchymal abnormalities, such as honeycombing, reticulation and ground-glass opacity. Thin-slices MDCT remains superior to MRI for morphological imaging. However, recent studies with ultra-short echo-time MRI showed image quality comparable to thin-slices MDCT. Several studies demonstrated the added value of chest MRI by using functional imaging, especially to detect and quantify inflammatory changes.We concluded that chest MRI could play a role in ILD patients to differentiate inflammatory and fibrotic changes and to assess efficacy of new ILD drugs.

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Bianciardi, Marta, Nicola Toschi, Jonathan R. Polimeni, Karleyton C. Evans, Himanshu Bhat, Boris Keil, Bruce R. Rosen, David A. Boas, and Lawrence L. Wald. "The pulsatility volume index: an indicator of cerebrovascular compliance based on fast magnetic resonance imaging of cardiac and respiratory pulsatility." Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences 374, no. 2067 (May 13, 2016): 20150184. http://dx.doi.org/10.1098/rsta.2015.0184.

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The influence of cardiac activity on the viscoelastic properties of intracranial tissue is one of the mechanisms through which brain–heart interactions take place, and is implicated in cerebrovascular disease. Cerebrovascular disease risk is not fully explained by current risk factors, including arterial compliance. Cerebrovascular compliance is currently estimated indirectly through Doppler sonography and magnetic resonance imaging (MRI) measures of blood velocity changes. In order to meet the need for novel cerebrovascular disease risk factors, we aimed to design and validate an MRI indicator of cerebrovascular compliance based on direct endogenous measures of blood volume changes. We implemented a fast non-gated two-dimensional MRI pulse sequence based on echo-planar imaging (EPI) with ultra-short repetition time (approx. 30–50 ms), which stepped through slices every approximately 20 s. We constrained the solution of the Bloch equations for spins moving faster than a critical speed to produce an endogenous contrast primarily dependent on spin volume changes, and an approximately sixfold signal gain compared with Ernst angle acquisitions achieved by the use of a 90° flip angle. Using cardiac and respiratory peaks detected on physiological recordings, average cardiac and respiratory MRI pulse waveforms in several brain compartments were obtained at 7 Tesla, and used to derive a compliance indicator, the pulsatility volume index (pVI). The pVI, evaluated in larger cerebral arteries, displayed significant variation within and across vessels. Multi-echo EPI showed the presence of significant pulsatility effects in both S 0 and signals, compatible with blood volume changes. Lastly, the pVI dynamically varied during breath-holding compared with normal breathing, as expected for a compliance indicator. In summary, we characterized and performed an initial validation of a novel MRI indicator of cerebrovascular compliance, which might prove useful to investigate brain–heart interactions in cerebrovascular disease and other disorders.

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Zhang, Rosaline, Hyunyeol Lee, Xia Zhao, Hee K. Song, Felix W. Wehrli, and Scott P. Bartlett. "2118 Solid-state MRI as a nonradiative alternative to computed tomography for craniofacial imaging." Journal of Clinical and Translational Science 2, S1 (June 2018): 28. http://dx.doi.org/10.1017/cts.2018.123.

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OBJECTIVES/SPECIFIC AIMS: Computed tomography (CT) enables 3-dimensional (3D) visualization of cortical bone structures with high spatial resolution, and thus has been the gold-standard method for evaluation and diagnosis of craniofacial skeletal pathologies. However, ionizing radiation and, in particular, repeated scanning for presurgery and postsurgery assessments, is of concern when applied to infants and young children. Recent advances in solid-state MRI allow the capture of the short-T2 signals in cortical bone while suppressing the signal from soft-tissue protons having T2 relaxation time 1–2 orders of magnitude longer (50–100 ms). One approach, a dual-radiofrequency (RF) pulse and ultrashort echo time (UTE) imaging based method, exploits different sensitivities of bone and soft tissue to different RF pulse widths and TEs. This study aims to demonstrate the feasibility of producing 3D renderings of the human skull and visualization of cranial sutures using the bone-selective MRI technique in comparison to CT. METHODS/STUDY POPULATION: Imaging technique: Two RF pulses differing in duration and amplitude are alternately applied in successive repetition time (TR) along the pulse train. Within each TR, 2 echoes are acquired. Acquisition of the first echo starts at the ramp-up of the encoding gradient (TE1), allowing for capture of signals with very short lifetimes (bone), while that of the second starts after a longer delay (TE2). In total, 4 echoes are obtained: ECHO11 (RF1TE1), ECHO12 (RF1TE2), ECHO21 (RF2TE1), and ECHO22 (RF2TE2). During reconstruction, ECHO11 is combined with ECHO21 and ECHO12 is combined with ECHO22, resulting in 2 images. The subtraction of these 2 images yields an enhanced bone contrast. Data acquisition/processing: The pulse sequence described above was applied for MR imaging of a human cadaveric skull and 2 adult human subjects in vivo, at 3T field strength (Siemens Prisma, Erlangen, Germany). Imaging parameters: TR/TE1/TE2=7/0.06/2.46 ms, RF1/RF2 durations=40/520 μs, flip angle=12°, matrix size=2563, field of view=2803 mm3, voxel size=1.1 mm isotropic, number of radial spokes=25,000, and scan time=6 minutes. Segmentation of bone voxels was performed using ITK-SNAP in a semi-automatic fashion, leading to 3D renderings of the skull. For comparison, a CT scan was also performed in the human cadaveric skull with 1 mm isotropic resolution. Validation: The biometric accuracy was assessed by measuring eight anatomic distances: (1) Maximum craniocaudal aperture of the right orbit. (2) Maximum craniocaudal aperture of the left orbit. (3) Maximum height of the mandible from chin point in the midline. (4) Maximum cranial length (5) Maximum cranial width. (6) Maximum height of piriform aperture. (7) Distance between lateral most aspect of mandibular condyles. (8) Distance between lateral most aspect of posterior hard palate in both CT- and MRI-based 3D renderings of the human cadaveric skull using Mimics software (Materialise®, Ghent, Belgium). These distances were compared with those directly measured on the cadaveric skull. RESULTS/ANTICIPATED RESULTS: Compares CT with the proposed MRI method on cadaveric human skull images, along with corresponding 3D renderings. Compared with CT, the 3D rendered images maintain most features over the entire head (e.g., zygomatic arch), except for appearance of some artifacts in the mandibular region. In vivo head images in 2 adult subjects: axial magnitude images and 3D rendering. In the axial images, bone voxels as well as the inner table of the cranium are clearly visualized, and cranial and spinal bone structures are well depicted in the 3D renderings. Some voxels were erroneously included or excluded in the renderings. The mean difference in measurements of the 8 anatomic distances was 6, 4, and 2 mm when comparing MRI Versus CT, MRI Versus in situ, and CT Versus in situ, respectively. DISCUSSION/SIGNIFICANCE OF IMPACT: Bone proton magnetization exhibits a substantial level of signal decay during the relatively long duration of RF2 due to its very short T2 relaxation time. In contrast, soft-tissue retains nearly the same level of signal intensities over all echoes. Thus, subtraction of ECHO22 from ECHO11, when compared with the difference between ECHO11 and ECHO12, enhances bone contrast from soft tissue. The proposed, dual-RF dual-echo 3D UTE imaging technique produces isotropic high-resolution bone-specified images in the whole head within a clinically feasible imaging time (6 min), leading to clear visualization of craniofacial skeletal structures. These are key components necessary for translation to the clinical setting. Optimization of postprocessing for more realistic 3D renderings and thus accurate anatomic measurements is currently being implemented. The proposed method’s potential as a nonradiative alternative to CT will then be thoroughly evaluated in pediatric patients.

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Doyle, Eamon K., Kristin Toy, Bertin Valdez, Jonathan M. Chia, Thomas Coates, and John C. Wood. "Ultra-short echo time images quantify high liver iron." Magnetic Resonance in Medicine 79, no. 3 (June 22, 2017): 1579–85. http://dx.doi.org/10.1002/mrm.26791.

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Mentrup, Detlef, and Holger Eggers. "Signal Decay Correction in 2D Ultra-Short Echo Time Imaging." Magnetic Resonance Materials in Physics, Biology and Medicine 19, no. 2 (May 2006): 62–70. http://dx.doi.org/10.1007/s10334-006-0028-0.

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Xiao, Dan, and Bruce J. Balcom. "Ultra-short echo time imaging with multiple echo refocusing for porous media T2 mapping." Journal of Magnetic Resonance 299 (February 2019): 33–41. http://dx.doi.org/10.1016/j.jmr.2018.12.003.

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Journal articles on the topic 'Ultra-short echo time (UTE)'

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