Optical coherence tomography (OCT) is a non-invasive imaging modality that suitable for accessing retinal diseases. Since the thickness and shape of the retinal layer are diagnostic indicators for many ophthalmic diseases, segmentation of the retinal layer in OCT images is a critical step. Automated segmentation of oct images has made many efforts but there are still some challenges, such as lack of context information, ambiguous boundaries and inconsistent prediction of retinal lesion regions. In this work, we propose a new framework of Densely Encoded Attention Networks (DEAN) that combines dense encoders with position attention in an U-architecture for retinal layers segmentation. Since the spatial position of each layer in OCT image is relatively fixed, we use convolution in dense connections to obtain diverse feature maps in the encoder and employ position attention to improve the spatial information of learning targets. Moreover, up-sampling and skip connections in the decoder are to restore resolution by the position index saved during down-sampling, while supplementing the corresponding pixels is to guide the network capturing the global context information. This method is evaluated on two public datasets, and the results demonstrate that our method is an effective strategy on improving the performance of segmenting the retinal layers.
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