Accelerating the 3D T1ρ mapping of cartilage using a signal-compensated robust tensor principal component analysis model

Abstract

Background: Magnetic resonance (MR) quantitative T 1ρ imaging has been increasingly used to detect the early stages of osteoarthritis. The small volume and curved surface of articular cartilage necessitate imaging with high in-plane resolution and thin slices for accurate T 1ρ measurement. Compared with 2D T 1ρ mapping, 3D T 1ρ mapping is free from artifacts caused by slice cross-talk and has a thinner slice thickness and full volume coverage. However, this technique needs to acquire multiple T 1ρ -weighted images with different spin-lock times, which results in a very long scan duration. It is highly expected that the scan time can be reduced in 3D T 1ρ mapping without compromising the T 1ρ quantification accuracy and precision.Methods: To accelerate the acquisition of 3D T 1ρ mapping without compromising the T 1ρ quantification accuracy and precision, a signal-compensated robust tensor principal component analysis method was proposed in this paper. The 3D T 1ρ -weighted images compensated at different spin-lock times were decomposed as a low-rank high-order tensor plus a sparse component. Poisson-disk random undersampling patterns were applied to k-space data in the phase-and partition-encoding directions in both retrospective and prospective experiments. Five volunteers were involved in this study. The fully sampled k-space data acquired from 3 volunteers were retrospectively undersampled at R=5.2, 7.7, and 9.7, respectively.Reference values were obtained from the fully sampled data. Prospectively undersampled data for R=5 and R=7 were acquired from 2 volunteers. Bland-Altman analyses were used to assess the agreement between the accelerated and reference T 1ρ measurements. The reconstruction performance was evaluated using the normalized root mean square error and the median of the normalized absolute deviation (MNAD) of the reconstructed T 1ρ -weighted images and the corresponding T 1ρ maps.Results: T 1ρ parameter maps were successfully estimated from T 1ρ -weighted images reconstructed using the proposed method for all accelerations. The accelerated T 1ρ measurements and reference values were in good agreement for R=5.2 (T 1ρ : 40.4±1.4 ms), R=7.7 (T 1ρ : 40.4±2.1 ms), and R=9.7 (T 1ρ : 40.9±2.2 ms) in the Bland-Altman analyses. The T 1ρ parameter maps reconstructed from the prospectively undersampled data also showed promising image quality using the proposed method. Conclusions:The proposed method achieves the 3D T 1ρ mapping of in vivo knee cartilage in eight minutes using a signal-compensated robust tensor principal component analysis method in image reconstruction.

Updates on Compositional MRI Mapping of the Cartilage: Emerging Techniques and Applications

“…Model‐based and CS reconstructions are still active research topics for accelerating cartilage compositional MRI techniques. In the literature, 51 a CS reconstruction using robust tensor principal component analysis (PCA) models was proposed to accelerate cartilage T 1ρ mapping, showing good agreement of T 1ρ values between CS and fully sampled (FS) acquisitions. A model‐based acceleration for diffusion imaging was proposed for musculoskeletal applications, and the feasibility of acceleration factors of 3.65 was shown without compromising diffusion data fidelity 52 …”

Accelerating Magnetic Resonance T1\r{ho} Mapping Using Simultaneously Spatial Patch-based and Parametric Group-based Low-rank Tensors (SMART)

“…The proposed method was evaluated on the T 1ρ mapping datasets of the brain collected from 6 volunteers on 3T scanners [12], [45]. The local institutional review board approved the experiments, and informed consent was obtained from each volunteer.…”

“…The 3D dataset was collected on a 3T scanner (uMR 790, United Imaging Healthcare, Shanghai, China) using a 32-channel head coil from two healthy volunteers (age: 26 ± 1 years). T 1ρ -weighted images were acquired using the fast spin echo (FSE) sequence for 2D imaging and the modulated flip angle technique in refocused imaging with an extended echo train (MATRIX) sequence for 3D imaging, both using a spin-lock pulse at the beginning of the sequence to generate the T 1ρ -weighting [12], [45]. The main imaging parameters that used in the 2D and 3D imaging applications are listed in Supplementary information Table S2.…”

MAGL regulates synovial macrophage polarization vis inhibition of mitophagy in osteoarthritic pain

“…Pathologically, OA is characterized by progressive articular cartilage degeneration, subchondral bone rebuilding, and synovial inflammation ( 3 ). Worldwide, knee OA is a growing public health issue and a major cause of disability in the elderly ( 4 , 5 ). Chronic pain is a hallmark symptom of OA, which often necessitates the need for medical care and contributes to a reduced quality of life, and increased healthcare costs.…”