Modality Cycles with Masked Conditional Diffusion for Unsupervised
Anomaly Segmentation in MRI
- URL: http://arxiv.org/abs/2308.16150v3
- Date: Thu, 2 Nov 2023 18:36:17 GMT
- Title: Modality Cycles with Masked Conditional Diffusion for Unsupervised
Anomaly Segmentation in MRI
- Authors: Ziyun Liang, Harry Anthony, Felix Wagner, Konstantinos Kamnitsas
- Abstract summary: Unsupervised anomaly segmentation aims to detect patterns that are distinct from any patterns processed during training.
This paper introduces Masked Modality Cycles with Conditional Diffusion (MMCCD), a method that enables segmentation of anomalies across diverse patterns in multimodal MRI.
We show that our method compares favorably to previous unsupervised approaches based on image reconstruction and denoising with autoencoders and diffusion models.
- Score: 2.5847188023177403
- License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
- Abstract: Unsupervised anomaly segmentation aims to detect patterns that are distinct
from any patterns processed during training, commonly called abnormal or
out-of-distribution patterns, without providing any associated manual
segmentations. Since anomalies during deployment can lead to model failure,
detecting the anomaly can enhance the reliability of models, which is valuable
in high-risk domains like medical imaging. This paper introduces Masked
Modality Cycles with Conditional Diffusion (MMCCD), a method that enables
segmentation of anomalies across diverse patterns in multimodal MRI. The method
is based on two fundamental ideas. First, we propose the use of cyclic modality
translation as a mechanism for enabling abnormality detection.
Image-translation models learn tissue-specific modality mappings, which are
characteristic of tissue physiology. Thus, these learned mappings fail to
translate tissues or image patterns that have never been encountered during
training, and the error enables their segmentation. Furthermore, we combine
image translation with a masked conditional diffusion model, which attempts to
`imagine' what tissue exists under a masked area, further exposing unknown
patterns as the generative model fails to recreate them. We evaluate our method
on a proxy task by training on healthy-looking slices of BraTS2021
multi-modality MRIs and testing on slices with tumors. We show that our method
compares favorably to previous unsupervised approaches based on image
reconstruction and denoising with autoencoders and diffusion models.
Related papers
- DiAD: A Diffusion-based Framework for Multi-class Anomaly Detection [55.48770333927732]
We propose a Difusion-based Anomaly Detection (DiAD) framework for multi-class anomaly detection.
It consists of a pixel-space autoencoder, a latent-space Semantic-Guided (SG) network with a connection to the stable diffusion's denoising network, and a feature-space pre-trained feature extractor.
Experiments on MVTec-AD and VisA datasets demonstrate the effectiveness of our approach.
arXiv Detail & Related papers (2023-12-11T18:38:28Z) - Introducing Shape Prior Module in Diffusion Model for Medical Image
Segmentation [7.7545714516743045]
We propose an end-to-end framework called VerseDiff-UNet, which leverages the denoising diffusion probabilistic model (DDPM)
Our approach integrates the diffusion model into a standard U-shaped architecture.
We evaluate our method on a single dataset of spine images acquired through X-ray imaging.
arXiv Detail & Related papers (2023-09-12T03:05:00Z) - Diffusion Models for Counterfactual Generation and Anomaly Detection in Brain Images [39.94162291765236]
We present a weakly supervised method to generate a healthy version of a diseased image and then use it to obtain a pixel-wise anomaly map.
We employ a diffusion model trained on healthy samples and combine Denoising Diffusion Probabilistic Model (DDPM) and Denoising Implicit Model (DDIM) at each step of the sampling process.
arXiv Detail & Related papers (2023-08-03T21:56:50Z) - Unsupervised Anomaly Detection in Medical Images Using Masked Diffusion
Model [7.116982044576858]
Masked Image Modeling (MIM) and Masked Frequency Modeling (MFM) in our self-supervised approach that enables models to learn visual representations from unlabeled data.
We evaluate our approach on datasets containing tumors and numerous sclerosis lesions.
arXiv Detail & Related papers (2023-05-31T14:04:11Z) - Self-Supervised Training with Autoencoders for Visual Anomaly Detection [61.62861063776813]
We focus on a specific use case in anomaly detection where the distribution of normal samples is supported by a lower-dimensional manifold.
We adapt a self-supervised learning regime that exploits discriminative information during training but focuses on the submanifold of normal examples.
We achieve a new state-of-the-art result on the MVTec AD dataset -- a challenging benchmark for visual anomaly detection in the manufacturing domain.
arXiv Detail & Related papers (2022-06-23T14:16:30Z) - Fast Unsupervised Brain Anomaly Detection and Segmentation with
Diffusion Models [1.6352599467675781]
We propose a method based on diffusion models to detect and segment anomalies in brain imaging.
Our diffusion models achieve competitive performance compared with autoregressive approaches across a series of experiments with 2D CT and MRI data.
arXiv Detail & Related papers (2022-06-07T17:30:43Z) - Diffusion Models for Medical Anomaly Detection [0.8999666725996974]
We present a novel weakly supervised anomaly detection method based on denoising diffusion implicit models.
Our method generates very detailed anomaly maps without the need for a complex training procedure.
arXiv Detail & Related papers (2022-03-08T12:35:07Z) - Explainable multiple abnormality classification of chest CT volumes with
AxialNet and HiResCAM [89.2175350956813]
We introduce the challenging new task of explainable multiple abnormality classification in volumetric medical images.
We propose a multiple instance learning convolutional neural network, AxialNet, that allows identification of top slices for each abnormality.
We then aim to improve the model's learning through a novel mask loss that leverages HiResCAM and 3D allowed regions.
arXiv Detail & Related papers (2021-11-24T01:14:33Z) - Modality Completion via Gaussian Process Prior Variational Autoencoders
for Multi-Modal Glioma Segmentation [75.58395328700821]
We propose a novel model, Multi-modal Gaussian Process Prior Variational Autoencoder (MGP-VAE), to impute one or more missing sub-modalities for a patient scan.
MGP-VAE can leverage the Gaussian Process (GP) prior on the Variational Autoencoder (VAE) to utilize the subjects/patients and sub-modalities correlations.
We show the applicability of MGP-VAE on brain tumor segmentation where either, two, or three of four sub-modalities may be missing.
arXiv Detail & Related papers (2021-07-07T19:06:34Z) - Improved Slice-wise Tumour Detection in Brain MRIs by Computing
Dissimilarities between Latent Representations [68.8204255655161]
Anomaly detection for Magnetic Resonance Images (MRIs) can be solved with unsupervised methods.
We have proposed a slice-wise semi-supervised method for tumour detection based on the computation of a dissimilarity function in the latent space of a Variational AutoEncoder.
We show that by training the models on higher resolution images and by improving the quality of the reconstructions, we obtain results which are comparable with different baselines.
arXiv Detail & Related papers (2020-07-24T14:02:09Z) - Manifolds for Unsupervised Visual Anomaly Detection [79.22051549519989]
Unsupervised learning methods that don't necessarily encounter anomalies in training would be immensely useful.
We develop a novel hyperspherical Variational Auto-Encoder (VAE) via stereographic projections with a gyroplane layer.
We present state-of-the-art results on visual anomaly benchmarks in precision manufacturing and inspection, demonstrating real-world utility in industrial AI scenarios.
arXiv Detail & Related papers (2020-06-19T20:41:58Z)
This list is automatically generated from the titles and abstracts of the papers in this site.
This site does not guarantee the quality of this site (including all information) and is not responsible for any consequences.