Six-Minute Knee MRI: A Comparison of Novel Approaches for Accelerated Imaging

BackgroundAccelerated knee MRI protocols using deep learning (DL)-based reconstruction, 3D acquisitions, and parallel imaging can significantly reduce scan times. These methods enhance patient throughput and comfort while maintaining diagnostic quality. However, their clinical efficacy and diagnostic performance across various knee pathologies requires systematic evaluation. PurposeTo evaluate the diagnostic performance and image quality of four accelerated knee MRI protocols ([~]6 minutes) compared with the standard conventional 2D FSE protocol ([~]15-30 minutes). Materials and MethodsThis prospective study enrolled adults with symptomatic knee pain between May 2021 and March 2022. All participants underwent five knee MRI protocols: a conventional 2D fast spin echo (FSE) protocol, a 2D FSE protocol with DL reconstruction, a 3D Cube protocol, a 3D quantitative double-echo steady-state (qDESS) protocol, and a thin-slice 2D FSE protocol. Five radiologists evaluated pathologies in joint tissues. Inter-reader and inter-method agreements were assessed using Gwets AC, with sensitivity and specificity calculated. Image diagnostic quality was evaluated using a Likert scale, and the Friedman was test used (p<0.05 indicative of statistically significant difference). ResultsA total of 32 participants were evaluated (14 men, aged 47{+/-}16 years). Of 160 total scans, 12 were excluded due to motion artifacts. Across pathologies, the 3D qDESS protocol had the highest inter-reader agreement for menisci (0.86) and cartilage (0.48), with sensitivities of 95% and 83%, respectively. The 2D DL protocol showed strong performance for bone marrow (sensitivity: 78%). Lastly, for effusion, both the 2D DL and 3D Cube protocols exhibited high inter-reader agreement (0.89 and 0.87, respectively). Diagnostic image quality scores exceeded were diagnostically acceptable in 95% of evaluations for menisci, bone marrow, and ligaments. ConclusionThe 2D DL, 3D Cube, and 3D qDESS protocols matched the diagnostic performance of the conventional protocol while reducing scan times to six minutes, improving workflow and patient experience.