3 research outputs found
Deep learning-based fully automatic segmentation of wrist cartilage in MR images
The study objective was to investigate the performance of a dedicated
convolutional neural network (CNN) optimized for wrist cartilage segmentation
from 2D MR images. CNN utilized a planar architecture and patch-based (PB)
training approach that ensured optimal performance in the presence of a limited
amount of training data. The CNN was trained and validated in twenty
multi-slice MRI datasets acquired with two different coils in eleven subjects
(healthy volunteers and patients). The validation included a comparison with
the alternative state-of-the-art CNN methods for the segmentation of joints
from MR images and the ground-truth manual segmentation. When trained on the
limited training data, the CNN outperformed significantly image-based and
patch-based U-Net networks. Our PB-CNN also demonstrated a good agreement with
manual segmentation (Sorensen-Dice similarity coefficient (DSC) = 0.81) in the
representative (central coronal) slices with large amount of cartilage tissue.
Reduced performance of the network for slices with a very limited amount of
cartilage tissue suggests the need for fully 3D convolutional networks to
provide uniform performance across the joint. The study also assessed inter-
and intra-observer variability of the manual wrist cartilage segmentation
(DSC=0.78-0.88 and 0.9, respectively). The proposed deep-learning-based
segmentation of the wrist cartilage from MRI could facilitate research of novel
imaging markers of wrist osteoarthritis to characterize its progression and
response to therapy
CNN 鈥恇ased fully automatic wrist cartilage volume quantification in MR images: A comparative analysis between different CNN architectures
Purpose Automatic measurement of wrist cartilage volume in MR images. Methods We assessed the performance of four manually optimized variants of the U鈥怤et architecture, nnU鈥怤et and Mask R鈥怌NN frameworks for the segmentation of wrist cartilage. The results were compared to those from a patch鈥恇ased convolutional neural network (CNN) we previously designed. The segmentation quality was assessed on the basis of a comparative analysis with manual segmentation. The best networks were compared using a cross鈥恦alidation approach on a dataset of 33 3D VIBE images of mostly healthy volunteers. Influence of some image parameters on the segmentation reproducibility was assessed. Results The U鈥怤et鈥恇ased networks outperformed the patch鈥恇ased CNN in terms of segmentation homogeneity and quality, while Mask R鈥怌NN did not show an acceptable performance. The median 3D DSC value computed with the U鈥怤et_AL (0.817) was significantly larger than DSC values computed with the other networks. In addition, the U鈥怤et_AL provided the lowest mean volume error (17%) and the highest Pearson correlation coefficient (0.765) with respect to the ground truth values. Of interest, the reproducibility computed using U鈥怤et_AL was larger than the reproducibility of the manual segmentation. Moreover, the results indicate that the MRI鈥恇ased wrist cartilage volume is strongly affected by the image resolution. Conclusions U鈥怤et CNN with attention layers provided the best wrist cartilage segmentation performance. In order to be used in clinical conditions, the trained network can be fine鈥恡uned on a dataset representing a group of specific patients. The error of cartilage volume measurement should be assessed independently using a non鈥怣RI method