Accelerated MRI of the knee. Quality and efficiency of compressed sensing

•Compressed Sensing can increase patient compliance and reduce healthcare cost for 3D knee MRI due to decreased scan times.•MRI scan time can be decreased by 34.39% for 2D CS 2 and 54.17% for 3D CS 10 with unchanged diagnostic certainty.•The new technique is especially valuable for fast 3D accelerations while SENSE could achieve similar results for 2D sequences. To evaluate potential clinical acceleration factors of Compressed SENSE (CS)11CS-compressed SENSE in direct comparison with SENSE for fat saturated (fs)22fs- fat saturated, proton density-weighted (PD)33PD- proton density-weighted 2D and 3D sequences of the knee. Twenty healthy volunteers were scanned with a 3 T scanner, all receiving a standard, fs 2D PD, three CS (CS 2, CS 3, CS 5) as well as time-equivalent SENSE accelerations (S 2, S 3, S 5). The fs 3D PD sequence was acquired with four CS (CS 6, CS 8, CS 10, CS 15) and equivalent SENSE (S 5.72, S 7.69, S 9.57, S 14) factors. Three independent readers rated the images. Signal-to-noise, contrast-to-noise, root-mean-square error and structural similarity index were analyzed for objective evaluation. Scan time decreased with increasing CS factor (2D CS 2: 145 s, 2D CS 3: 95 s, 2D CS 5: 57 s, 3D CS 6: 293 s, 3D CS 8: 220 s, 3D CS 10: 176 s, 3D CS 15: 119 s). The 2D standard sequence was rated best for diagnostic certainty and overall image impression with an average of 4.97 ± 0.10 and 4.80 ± 0.24 (all p