To accelerate the quantitative ultrashort echo time imaging using a time-efficient 3D multispoke Cones sequence with magnetization transfer (3D UTE-Cones-MT) and signal modeling.A UTE-Cones-MT acquisition scheme per MT preparation modified rectangular pulse (RP) approximation was developed for two-pool modeling of macromolecular water components including their relative fractions, relaxation times exchange rates. Numerical simulation cadaveric specimens, human Achilles tendon bovine cortical...

To develop an accurate T1 measurement method for short T2 tissues using a combination of 3-dimensional ultrashort echo time cones actual flip angle imaging technique and variable repetition (3D UTE-Cones AFI-VTR) on clinical 3T scanner.First, the longitudinal magnetization mapping function excitation pulse was obtained with 3D AFI method, which provided information about efficiency B1 inhomogeneity. Then, derived substituted into VTR fitting to generate maps. Numerical simulation phantom...

MRI biomarkers such as T 2 , * and 1rho have been widely used, but are confounded by the magic angle effect. The purpose of this study is to investigate use two‐dimensional ultrashort echo time magnetization transfer (UTE‐MT) sequence for potential independent MR biomarkers. Magnetization was investigated in cadaveric Achilles tendon samples using UTE‐MT at five MT powers frequency offsets ranging from 50 kHz. protocol applied sample orientations 0 90° relative B field. results were analyzed...

To develop a deep learning-based method for knee menisci segmentation in 3D ultrashort echo time (UTE) cones MR imaging, and to automatically determine relaxation times, namely the T1, T1

Purpose To measure T 1 relaxations for the major tissues in whole knee joints on a clinical 3T scanner. Methods The 3D UTE‐Cones actual flip angle imaging (AFI) method was used to map transmission radiofrequency field (B ) both short and long 2 tissues, which then correct variable (VFA) fitting generate accurate maps. Numerical simulation carried out investigate accuracy of measurement range values, excitation pulse durations, B errors. Then, AFI‐VFA applied healthy volunteers ( N = 16)...

Purpose To investigate high contrast imaging of short T 2 tissues with a three‐dimensional double adiabatic inversion recovery prepared ultrashort echo time Cones (3D DIR‐UTE‐Cones) sequence. Methods The sequence used two sequential pulses to suppress signals from long tissues, followed by multispoke UTE acquisition detect tissues. are identical center frequency located at the water peak, but spectral width is broad enough cover both and fat frequencies. feasibility this technique was...

Purpose To develop a 3D adiabatic T 1ρ prepared ultrashort echo time cones (3D AdiabT UTE‐Cones) sequence for whole knee imaging on clinical 3T scanner. Methods A train of full passage pulses were used spin locking, followed by time‐efficient multispoke UTE acquisition to detect signals from both short and long 2 tissues in the joint. modified signal model was proposed data fitting. The feasibility this UTE‐Cones technique demonstrated through numerical simulation, phantom, ex vivo sample...

Background Water signal contamination is a major challenge for direct ultrashort echo time (UTE) imaging of myelin in vivo because water contributes most the signals detected white matter. Purpose To validate new short repetition (TR) adiabatic inversion recovery (STAIR) prepared UTE (STAIR-UTE) sequence designed to suppress and allow T2 protons matter using clinical 3-T scanner. Materials Methods In this prospective study, an optimization framework was used obtain optimal nulling STAIR-UTE...

Background Signal contamination from long T2 water is a major challenge in direct imaging of myelin with MRI. Nulling the unwanted signals can be achieved an inversion recovery (IR) preparation pulse to null white matter within brain. The remaining ultrashort signal detected echo time (UTE) sequence. Purpose To develop patient-specific whole-brain three-dimensional double-echo sliding (DESIRE) UTE Materials and Methods DESIRE sequence generates series IR images different times during single...

Purpose To investigate tricomponent analysis of human cortical bone using a multipeak fat signal model with 3D ultrashort TE Cones sequences on clinical 3T scanner. Methods Tricomponent fitting bound water, pore and content spectra was proposed for imaging bone. Three‐dimensional acquisitions combined were used to water fractions, as well fraction in Feasibility studies performed 9 specimens regions interest selected from the endosteum periosteum 4 circumferential regions. Microcomputed...

Purpose To investigate direct imaging of trabecular bone using a 3D adiabatic inversion recovery prepared ultrashort TE cones (3D IR‐UTE‐Cones) sequence. Methods The proposed IR‐UTE‐Cones sequence used broadband pulse together with short TR/TI combination to suppress signals from long T 2 tissues such as muscle and marrow fat, followed by multispoke UTE acquisition detect signal water components in bone. feasibility this technique for robust suppression was first demonstrated through...

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 extracellular through assessment of exchange protons amide groups on iodinated contrast agents bulk water. It is possible to estimate osteoarthritic joint using acidoCEST MRI. However, conventional MR sequences cannot image deep layers cartilage, meniscus, ligaments, other musculoskeletal tissues that...

Purpose We present three-dimensional ultrashort echo time Cones (3D UTE Cones) techniques for quantification of total water T1 ( ), bound and pore ) in vitro vivo using a 3 Tesla (T) scanner. Methods , were measured with (3D) adiabatic inversion recovery Cone (IR-Cone) sequences. Two-dimensional (2D) nonselective (UTE) techniques, including saturation recovery, variable repetition times (TRs), (IR) preparation approaches compared 3D-Cones on bovine cortical bone samples (n = 8). The 3D...

We report a novel three‐dimensional (3D) ultrashort echo time (UTE) sequence employing Cones trajectory and T 1ρ preparation (UTE‐Cones‐ ) for quantitative assessment of short 2 tissues in the musculoskeletal system. A basic 3D UTE‐Cones was combined with spin‐locking pulse contrast. relatively TR used to decrease scan time, which required 1 measurement compensation using data acquisitions variable TRs. Another strategy reduce total acquire multiple spokes ( N sp after each fat saturation....

Bone stress injury (BSI) incidents have been increasing amongst athletes in recent years as a result of more intense sporting activities. Cortical bone the tibia and fibula is one most common BSI sites. Nowadays, clinical magnetic resonance imaging (MRI) recommended technique for diagnosis at an early stage. However, MRI focuses on edema observations surrounding soft tissues, rather than injured components bone. Specifically, both normal are invisible conventional MRI. In contrast,...