33 research outputs found
A Multilayer Markovian Model for Change Detection in Aerial Image Pairs with Large Time Differences
International audienceIn this paper, we propose a Multilayer Markovian model for change detection in registered aerial image pairs with large time differences. A Three Layer Markov Random Field takes into account information from two different sets of features namely the Modified HOG (Histogram of Oriented Gradients) difference and the Gray-Level (GL) Difference. The third layer is the resultant combination of the two layers. Thus we integrate both the texture level as well as the pixel level information to generate the final result. The proposed model uses pairwise interaction retaining the sub-modularity condition for energy. Hence a global energy optimization can be achieved using a standard min-cut/ max flow algorithm ensuring homogeneity in the connected regions
Treatment Practices in Optic Nerve Glioma
Optic nerve glioma (OPG) is a rare tumor in children and adolescents. It comprises 1–5% of central nervous system tumors. It can be sporadic or associated with the neurofibromatosis 1 (NF1) gene. These are usually slow-growing tumors and may remain localized to the optic nerve or can have encroached upon adjoining structures like optic chiasma, opposite optic nerve, and hypothalamus. So, there may be decreased or loss of vision, proptosis, focal neurological symptoms, precocious puberty, and short stature. Due to the involvement of these critical structures, its treatment should be based on multidisciplinary consensus. The treatment modalities include surgery, RT, and chemotherapy. The aim of the treatment should be to preserve vision. However, the timing and selection of optimal treatment modalities are always a clinical dilemma. Recently, there have been promising results with newer techniques of radiotherapy and chemotherapy
A generalized framework to predict continuous scores from medical ordinal labels
Many variables of interest in clinical medicine, like disease severity, are
recorded using discrete ordinal categories such as normal/mild/moderate/severe.
These labels are used to train and evaluate disease severity prediction models.
However, ordinal categories represent a simplification of an underlying
continuous severity spectrum. Using continuous scores instead of ordinal
categories is more sensitive to detecting small changes in disease severity
over time. Here, we present a generalized framework that accurately predicts
continuously valued variables using only discrete ordinal labels during model
development. We found that for three clinical prediction tasks, models that
take the ordinal relationship of the training labels into account outperformed
conventional multi-class classification models. Particularly the continuous
scores generated by ordinal classification and regression models showed a
significantly higher correlation with expert rankings of disease severity and
lower mean squared errors compared to the multi-class classification models.
Furthermore, the use of MC dropout significantly improved the ability of all
evaluated deep learning approaches to predict continuously valued scores that
truthfully reflect the underlying continuous target variable. We showed that
accurate continuously valued predictions can be generated even if the model
development only involves discrete ordinal labels. The novel framework has been
validated on three different clinical prediction tasks and has proven to bridge
the gap between discrete ordinal labels and the underlying continuously valued
variables
Federated Learning for Breast Density Classification: A Real-World Implementation
Building robust deep learning-based models requires large quantities of
diverse training data. In this study, we investigate the use of federated
learning (FL) to build medical imaging classification models in a real-world
collaborative setting. Seven clinical institutions from across the world joined
this FL effort to train a model for breast density classification based on
Breast Imaging, Reporting & Data System (BI-RADS). We show that despite
substantial differences among the datasets from all sites (mammography system,
class distribution, and data set size) and without centralizing data, we can
successfully train AI models in federation. The results show that models
trained using FL perform 6.3% on average better than their counterparts trained
on an institute's local data alone. Furthermore, we show a 45.8% relative
improvement in the models' generalizability when evaluated on the other
participating sites' testing data.Comment: Accepted at the 1st MICCAI Workshop on "Distributed And Collaborative
Learning"; add citation to Fig. 1 & 2 and update Fig.