Work

Deep learning CAIPIRINHA-accelerated 3D MRI of the knee cartilage at 7 Tesla

Year: 2025

Type: article

Abstract: Purpose To investigate the feasibility and degree of scan-time reduction that can be achieved by deep learning (DL)-reconstruction in 3D dual-echo steady-state (DESS) knee-cartilage imaging accelerated with CAIPIRINHA (controlled aliasing in parallel imaging results in higher acceleration) at 7 Tesla (T). Methods 35 knee joints of 18 volunteers were imaged using an isotropic fat-suppressed DL-reconstructed CAIPIRINHA (controlled aliasing in parallel imaging results in higher acceleration) DESS sequence (CAIPIRINHA DL ) with an isotropic resolution of 0.25 mm. CAIPIRINHA DL acquisitions were accelerated four-, six-, eight-, and twelve-fold (CAIPIRINHA DL4 -CAIPIRINHA DL12 ), and compared to a state-of-the-art, fourfold accelerated GRAPPA (generalized autocalibrating partially parallel acquisitions) DESS acquisition (GRAPPA 4 ) with matched spatial-resolution. Three readers rated image-quality criteria. Rating differences were characterized with Friedman's analysis of variance. Inter-reader agreement was assessed for grading of incidental cartilage lesions. Results CAIPIRINHA DL6 had the shortest acquisition time (4:04 min) among sequences whose images were rated in the best category, with no statistically significant difference (p > 0.999) to GRAPPA 4 (5:53 min). The overall quality of CAIPIRINHA DL8 and CAIPIRINHA DL12 images was rated lower than GRAPPA 4 images, while artifacts were rated significantly more severe (p < 0.001, each). Inter-reader agreement for cartilage lesion grading ranged from almost perfect for CAIPIRINHA DL4 and GRAPPA 4 (κ = 0.90, each) to moderate for CAIPIRINHA DL12 (κ = 0.52). Conclusions The quality of DL-reconstructed 3D DESS images acquired at 7 Tesla with four- and six-fold CAIPIRINHA-based acceleration was equivalent to that of 3D-DESS images acquired with four-fold GRAPPA-based acceleration. These findings suggest the feasibility of DL-reconstructions for imaging of the knee cartilage at 7 Tesla field strength.

Source: European Journal of Radiology

DOI: 10.1016/j.ejrad.2025.112287