130 research outputs found
Quantifying the effects of data augmentation and stain color normalization in convolutional neural networks for computational pathology
Stain variation is a phenomenon observed when distinct pathology laboratories
stain tissue slides that exhibit similar but not identical color appearance.
Due to this color shift between laboratories, convolutional neural networks
(CNNs) trained with images from one lab often underperform on unseen images
from the other lab. Several techniques have been proposed to reduce the
generalization error, mainly grouped into two categories: stain color
augmentation and stain color normalization. The former simulates a wide variety
of realistic stain variations during training, producing stain-invariant CNNs.
The latter aims to match training and test color distributions in order to
reduce stain variation. For the first time, we compared some of these
techniques and quantified their effect on CNN classification performance using
a heterogeneous dataset of hematoxylin and eosin histopathology images from 4
organs and 9 pathology laboratories. Additionally, we propose a novel
unsupervised method to perform stain color normalization using a neural
network. Based on our experimental results, we provide practical guidelines on
how to use stain color augmentation and stain color normalization in future
computational pathology applications.Comment: Accepted in the Medical Image Analysis journa
HookNet: multi-resolution convolutional neural networks for semantic segmentation in histopathology whole-slide images
We propose HookNet, a semantic segmentation model for histopathology
whole-slide images, which combines context and details via multiple branches of
encoder-decoder convolutional neural networks. Concentricpatches at multiple
resolutions with different fields of view are used to feed different branches
of HookNet, and intermediate representations are combined via a hooking
mechanism. We describe a framework to design and train HookNet for achieving
high-resolution semantic segmentation and introduce constraints to guarantee
pixel-wise alignment in feature maps during hooking. We show the advantages of
using HookNet in two histopathology image segmentation tasks where tissue type
prediction accuracy strongly depends on contextual information, namely (1)
multi-class tissue segmentation in breast cancer and, (2) segmentation of
tertiary lymphoid structures and germinal centers in lung cancer. Weshow the
superiority of HookNet when compared with single-resolution U-Net models
working at different resolutions as well as with a recently published
multi-resolution model for histopathology image segmentatio
Context-aware stacked convolutional neural networks for classification of breast carcinomas in whole-slide histopathology images
Automated classification of histopathological whole-slide images (WSI) of
breast tissue requires analysis at very high resolutions with a large
contextual area. In this paper, we present context-aware stacked convolutional
neural networks (CNN) for classification of breast WSIs into normal/benign,
ductal carcinoma in situ (DCIS), and invasive ductal carcinoma (IDC). We first
train a CNN using high pixel resolution patches to capture cellular level
information. The feature responses generated by this model are then fed as
input to a second CNN, stacked on top of the first. Training of this stacked
architecture with large input patches enables learning of fine-grained
(cellular) details and global interdependence of tissue structures. Our system
is trained and evaluated on a dataset containing 221 WSIs of H&E stained breast
tissue specimens. The system achieves an AUC of 0.962 for the binary
classification of non-malignant and malignant slides and obtains a three class
accuracy of 81.3% for classification of WSIs into normal/benign, DCIS, and IDC,
demonstrating its potentials for routine diagnostics
A Survey on Deep Learning in Medical Image Analysis
Deep learning algorithms, in particular convolutional networks, have rapidly
become a methodology of choice for analyzing medical images. This paper reviews
the major deep learning concepts pertinent to medical image analysis and
summarizes over 300 contributions to the field, most of which appeared in the
last year. We survey the use of deep learning for image classification, object
detection, segmentation, registration, and other tasks and provide concise
overviews of studies per application area. Open challenges and directions for
future research are discussed.Comment: Revised survey includes expanded discussion section and reworked
introductory section on common deep architectures. Added missed papers from
before Feb 1st 201
Comparison of Different Methods for Tissue Segmentation in Histopathological Whole-Slide Images
Tissue segmentation is an important pre-requisite for efficient and accurate
diagnostics in digital pathology. However, it is well known that whole-slide
scanners can fail in detecting all tissue regions, for example due to the
tissue type, or due to weak staining because their tissue detection algorithms
are not robust enough. In this paper, we introduce two different convolutional
neural network architectures for whole slide image segmentation to accurately
identify the tissue sections. We also compare the algorithms to a published
traditional method. We collected 54 whole slide images with differing stains
and tissue types from three laboratories to validate our algorithms. We show
that while the two methods do not differ significantly they outperform their
traditional counterpart (Jaccard index of 0.937 and 0.929 vs. 0.870, p < 0.01).Comment: Accepted for poster presentation at the IEEE International Symposium
on Biomedical Imaging (ISBI) 201
Pathologists' first opinions on barriers and facilitators of computational pathology adoption in oncological pathology: an international study.
Computational pathology (CPath) algorithms detect, segment or classify cancer in whole slide images, approaching or even exceeding the accuracy of pathologists. Challenges have to be overcome before these algorithms can be used in practice. We therefore aim to explore international perspectives on the future role of CPath in oncological pathology by focusing on opinions and first experiences regarding barriers and facilitators. We conducted an international explorative eSurvey and semi-structured interviews with pathologists utilizing an implementation framework to classify potential influencing factors. The eSurvey results showed remarkable variation in opinions regarding attitude, understandability and validation of CPath. Interview results showed that barriers focused on the quality of available evidence, while most facilitators concerned strengths of CPath. A lack of consensus was present for multiple factors, such as the determination of sufficient validation using CPath, the preferred function of CPath within the digital workflow and the timing of CPath introduction in pathology education. The diversity in opinions illustrates variety in influencing factors in CPath adoption. A next step would be to quantitatively determine important factors for adoption and initiate validation studies. Both should include clear case descriptions and be conducted among a more homogenous panel of pathologists based on sub specialization
- …