10 A. Chaudhari et al.
5 Discussion and Conclusion
In this study, we demonstrated that transfer learning can be effectively used to
perform SR on MRI sequences with varied contrasts that are used clinically and
in epidemiological studies, even with a small training dataset. The dual-contrast
DESS sequence was able to maintain a considerably higher resolution and detail
than the comparison methods. It is important to note that since the SR was
carried out only in one dimension of the 3D dataset, the image enhancements in
Figs. 3 and 4 are more prominent in the left-right direction anatomically, which
is also the same direction of the displayed images.
The MRSR approach maintained comparable T
2
relaxation times between
the ground-truth. A pixel-wise CV of 3% has shown to be adequate for use in OA
studies and a CCC of over 0.90 indicated excellent reproducibility compared to
the ground-truth [9]. With MRSR, slices can be acquired with a higher section
thickness for accurate T
2
measurement, while enabling super-resolution for per-
forming high-resolution MRI scans, which was not possible previously due to
SNR limitations. Interestingly enough, all methods over-estimated T
2
values,
likely because the thin cartilage has two major divisions (deep and superficial),
where the deep cartilage has lower signal. Blurring from the superficial carti-
lage would increase signal in the deeper layer, leading to a higher T
2
value.
Performing layer-wise T
2
values will be important in future studies.
In conclusion, we demonstrated how SR enhanced through-plane resolution in
MRI and maintained quantitative accuracy of the T
2
relaxation time biomarker.
MRSR outperforms conventional and state-of-the-art resolution enhancement
methods and has potential for use in clinical and research studies.
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