Table 2. Accuracy (MD) of laminar cartilage T2 derived from fully automated CNN-based segmentation with the first echo model and with the 7-echoes model versus manual segmentation with quality control in various femorotibial joint regions of interest and layers (deep and SF).
| Cartilage region |
7-echoes CNN vs. manual | First echo CNN vs. manual | |||||
|---|---|---|---|---|---|---|---|
| MD ± SD | 95% CI | P | MD ± SD | 95% CI | P | ||
| FTJ | |||||||
| Deep | 0.0±0.6 | −0.1 to 0.2 | 0.828 | 0.4±0.7 | 0.3 to 0.6 | <0.001 | |
| SF | 1.1±0.7 | 1.0 to 1.3 | <0.001 | 2.3±1.4 | 2.0 to 2.7 | <0.001 | |
| MFTC | |||||||
| Deep | 0.0±0.9 | −0.2 to 0.2 | 0.998 | 0.0±1.0 | −0.2 to 0.3 | 0.838 | |
| SF | 1.3±0.9 | 1.1 to 1.5 | <0.001 | 1.9±1.6 | 1.5 to 2.3 | <0.001 | |
| LFTC | |||||||
| Deep | 0.0±0.6 | −0.1 to 0.2 | 0.675 | 0.9±0.8 | 0.7 to 1.1 | <0.001 | |
| SF | 1.0±0.9 | 0.8 to 1.3 | <0.001 | 2.7±1.9 | 2.3 to 3.2 | <0.001 | |
| MT | |||||||
| Deep | −0.1±0.9 | −0.3 to 0.1 | 0.410 | −0.2±1.1 | −0.5 to 0.0 | 0.080 | |
| SF | 0.6±0.9 | 0.4 to 0.8 | <0.001 | 1.4±1.9 | 1.0 to 1.9 | <0.001 | |
| cMF | |||||||
| Deep | 0.1±1.4 | −0.2 to 0.4 | 0.603 | 0.3±1.3 | 0.0 to 0.6 | 0.082 | |
| SF | 1.9±1.4 | 1.6 to 2.2 | <0.001 | 2.4±2.1 | 1.9 to 2.9 | <0.001 | |
| LT | |||||||
| Deep | −0.3±0.5 | −0.4 to −0.2 | <0.001 | 0.4±0.8 | 0.3 to 0.6 | <0.001 | |
| SF | 0.1±0.7 | 0.0 to 0.3 | 0.070 | 1.6±2.0 | 1.1 to 2.1 | <0.001 | |
| cLF | |||||||
| Deep | 0.4±1.1 | 0.1 to 0.6 | 0.008 | 1.3±1.4 | 1.0 to 1.6 | <0.001 | |
| SF | 1.9±1.6 | 1.5 to 2.3 | <0.001 | 3.9±2.5 | 3.3 to 4.5 | <0.001 | |
Results are for 71 baseline data sets. MD, mean difference; SD, standard deviation; SF, superficial; CNN, convolutional neural network; CI, confidence interval; FTJ, femorotibial joint; MFTC, medial femorotibial compartment; LFTC, lateral femorotibial compartment, MT, medial tibia, cMF, central (weight-bearing) medial femur; LT, lateral tibia, cLF, central (weight-bearing) lateral femur.