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Byra M., Wu M.♦, Zhang X.♦, Jang H.♦, Ma Y-J.♦, Chang E.Y.♦, Shah S.♦, Du J.♦, Knee menisci segmentation and relaxometry of 3D ultrashort echo time cones MR imaging using attention U‐Net with transfer learning,
Magnetic Resonance in Medicine, ISSN: 1522-2594, DOI: 10.1002/mrm.27969, Vol.83, No.3, pp.1109-1122, 2020Streszczenie: Purpose: To develop a deep learning-based method for knee menisci segmentation in 3D ultrashort echo time (UTE) cones MR imaging, and to automatically determine MR relaxation times, namely the T1, T1ρ, and T2* parameters, which can be used to assess knee osteoarthritis (OA). Methods: Whole knee joint imaging was performed using 3D UTE cones sequences to collect data from 61 human subjects. Regions of interest (ROIs) were outlined by 2 experienced radiologists based on subtracted T1ρ-weighted MR images. Transfer learning was applied to develop 2D attention U-Net convolutional neural networks for the menisci segmentation based on each radiologist's ROIs separately. Dice scores were calculated to assess segmentation performance. Next, the T1, T1ρ, T2* relaxations, and ROI areas were determined for the manual and automatic segmentations, then compared. Results: The models developed using ROIs provided by 2 radiologists achieved high Dice scores of 0.860 and 0.833, while the radiologists' manual segmentations achieved a Dice score of 0.820. Linear correlation coefficients for the T1, T1ρ, and T2* relaxations calculated using the automatic and manual segmentations ranged between 0.90 and 0.97, and there were no associated differences between the estimated average meniscal relaxation parameters. The deep learning models achieved segmentation performance equivalent to the inter-observer variability of 2 radiologists. Conclusion: The proposed deep learning-based approach can be used to efficiently generate automatic segmentations and determine meniscal relaxations times. The method has the potential to help radiologists with the assessment of meniscal diseases, such as OA. Słowa kluczowe: deep learning, menisci, osteoarthritis, quantitative MR, segmentation Afiliacje autorów:
Byra M. | - | IPPT PAN | Wu M. | - | University of California (US) | Zhang X. | - | University of California (US) | Jang H. | - | University of California (US) | Ma Y-J. | - | University of California (US) | Chang E.Y. | - | University of California (US) | Shah S. | - | University of California (US) | Du J. | - | University of California (US) |
| | 100p. |
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Byra M., Hentzen E.♦, Du J.♦, Andre M.♦, Chang E.Y.♦, Shah S.♦, Assessing the performance of morphologic and echogenic features in median nerve ultrasound for carpal tunnel syndrome diagnosis,
Journal of Ultrasound in Medicine, ISSN: 0278-4297, DOI: 10.1002/jum.15201, Vol.39, No.6, pp.1165-1174, 2020Streszczenie: Objectives: To assess the feasibility of using ultrasound (US) image features related to the median nerve echogenicity and shape for carpal tunnel syndrome (CTS) diagnosis. Methods: In 31 participants (21 healthy participants and 10 patients with CTS), US images were collected with a 30-MHz transducer from median nerves at the wrist crease in 2 configurations: a neutral position and with wrist extension. Various morphologic features, including the cross-sectional area (CSA), were calculated to assess the nerve shape. Carpal tunnel syndrome commonly results in loss of visualization of the nerve fascicular pattern on US images. To assess this phenomenon, we developed a nerve-tissue contrast index (NTI) method. The NTI is a ratio of average brightness levels of surrounding tissue and the median nerve, both calculated on the basis of a US image. The area under the curve (AUC) from a receiver operating characteristic curve analysis and t test were used to assess the usefulness of the features for differentiation of patients with CTS from control participants. Results: We obtained significant differences in the CSA and NTI parameters between the patients with CTS and control participants (P < .01), with the corresponding highest AUC values equal to 0.885 and 0.938, respectively. For the remaining investigated morphologic features, the AUC values were less than 0.685, and the differences in means between the patients and control participants were not statistically significant (P > .10). The wrist configuration had no impact on differences in average parameter values (P > .09). Conclusions: Patients with CTS can be differentiated from healthy individuals on the basis of the median nerve CSA and echogenicity. Carpal tunnel syndrome is not manifested in a change of the median nerve shape that could be related to circularity or contour variability. Słowa kluczowe: carpal tunnel syndrome, cross-sectional area, echogenicity, median nerve, morphologic features, ultrasound Afiliacje autorów:
Byra M. | - | IPPT PAN | Hentzen E. | - | inna afiliacja | Du J. | - | University of California (US) | Andre M. | - | University of California (US) | Chang E.Y. | - | University of California (US) | Shah S. | - | University of California (US) |
| | 70p. |
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Byra M., Wan L.♦, Wong J.H.♦, Du J.♦, Shah SB.♦, Andre M.P.♦, Chang E.Y.♦, Quantitative ultrasound and b-mode image texture featurescorrelate with collagen and myelin content in human ulnarnerve fascicles,
ULTRASOUND IN MEDICINE AND BIOLOGY, ISSN: 0301-5629, DOI: 10.1016/j.ultrasmedbio.2019.02.019, Vol.45, No.7, pp.1830-1840, 2019Streszczenie: We investigate the usefulness of quantitative ultrasound and B-mode texture features for characterization of ulnar nerve fascicles. Ultrasound data were acquired from cadaveric specimens using a nominal 30-MHz probe. Next, the nerves were extracted to prepare histology sections. Eighty-five fascicles were matched between the B-mode images and the histology sections. For each fascicle image, we selected an intra-fascicular region of interest. We used histology sections to determine features related to the concentration of collagen and myelin and ultrasound data to calculate the backscatter coefficient (–24.89 ± 8.31 dB), attenuation coefficient (0.92 ± 0.04 db/cm-MHz), Nakagami parameter (1.01 ± 0.18) and entropy (6.92 ± 0.83), as well as B-mode texture features obtained via the gray-level co-occurrence matrix algorithm. Significant Spearman rank correlations between the combined collagen and myelin concentrations were obtained for the backscatter coefficient (R = –0.68), entropy (R = –0.51) and several texture features. Our study indicates that quantitative ultrasound may potentially provide information on structural components of nerve fascicles. Słowa kluczowe: nerve, quantitative ultrasound, high frequency, histology, pattern recognition, texture analysis Afiliacje autorów:
Byra M. | - | IPPT PAN | Wan L. | - | University of California (US) | Wong J.H. | - | University of California (US) | Du J. | - | University of California (US) | Shah SB. | - | University of California (US) | Andre M.P. | - | University of California (US) | Chang E.Y. | - | University of California (US) |
| | 70p. |