OF-UMRN: Uncertainty-guided multitask regression network aided by optical flow for fully automated comprehensive
Chengqian Zhao1, Dengwang Li2, Cheng Feng3
1Shandong Key Laboratory of Medical Physics and Image Processing, Shandong Institute of Industrial Technology for Health Sciences and Precision Medicine, School of Physics and Electronics, Shandong Normal University, Jinan, Shandong, China; Department of Medical Imaging, Western University, London, ON, Canada; Digital Imaging Group, London, ON, Canada.
Abstract:
Fully automated comprehensive analysis of carotid artery (localization of range of interest (ROI), direct quantitative measurement and segmentation of lumen diameter (CALD) and intima-media thickness (CIMT), and motion estimation of the carotid wall) is a reliable auxiliary diagnosis of cardiovascular diseases, which relieves physicians from laborious workloads. No work has achieved fully automated comprehensive analysis of carotid artery due to five intractable challenges: (1) The heavy reliance on experienced carotid physicians for the selection of ROI limits fully automated studies. (2) The weak structural information of intima-media thickness increases the difficulty of feature encoding. (3) The radial motion of the carotid wall results in the lack of discriminant features of boundaries. (4) Diseased carotid arteries lose many expression features. (5) Optimal weights of multitask regression are hard to tune manually. In this paper, we propose a novel uncertainty-guided multitask regression network aided by optical flow named OF-UMRN to solve the intractable challenges. The four modules and three innovations of the OF-UMRN take their responsibility. OF-UMRN takes localization and mapping of ROI as a pre-processing. It achieves direct quantitative measurement and segmentation by a multitask regression network. And we creatively model homoscedastic uncertainty to automated tune the weights of the two tasks optimally. The OF-UMRN adopts a bidirectional mechanism to encode the optical flow used to predict the carotid wall's motion fields. More importantly, we creatively propose a dual optimization module based on the co-promotion between segmentation and motion estimation to improve the performance of radially moving and diseased carotid arteries. Therefore, the OF-UMRN makes the most of the pathological relationship between multiple objects and co-promotion between various tasks. Extensive experiments on US sequences of 101 patients have demonstrated the superior performance of OF-UMRN on the fully automated comprehensive analysis of the carotid artery. Therefore the OF-UMRN has excellent potential in clinical disease diagnoses and assessments of the carotid artery.
