• 摘要: OCT视网膜图像中存在着噪声和散斑,单一的提取空间特征往往容易遗漏一些重要信息,导致不能准确地分割目标区域。而OCT图像本身存在光谱频域特征,针对OCT图像的频域特征,本文基于U-Net和快速傅立叶卷积提出一种新的双编码器模型以提高对OCT图像视网膜层、液体的分割性能,提出的频域编码器可以提取图像频域信息并通过快速傅里叶卷积转换为空间信息,将很好地弥补单一空间编码器遗漏特征信息的不足。经过与其他经典模型的对比和消融实验,结果表明,随着频域编码器的添加,该模型能有效提升对视网膜层和液体的分割性能,平均Dice系数和mIoU相较于U-Net均提高2%,相较于ReLayNet分别提高8%和4%,其中对液体的分割提升尤为明显,相较于U-Net 模型Dice系数提高了10%。

       

      Abstract: There are noises and speckles in OCT retinal images, and a single extraction of spatial features is often easy to miss some important information. Therefore, the target region cannot be accurately segmented. OCT images themselves have spectral frequency domain characteristics. Aiming at the frequency domain characteristics of OCT images, this paper proposes a new dual encoder model based on U-Net and fast Fourier convolution to improve the segmentation performance of the retinal layer and liquid in OCT images. The proposed frequency encoder can extract image frequency domain information and convert it into spatial information through fast Fourier convolution. The lack of feature information that can be omitted by a single space encoder will be well-complemented. After comparison with other classical models and ablation experiments, the results show that with the addition of a frequency domain encoder, the model can effectively improve the segmentation performance of the retinal layer and liquid. Both average Dice coefficient and mIoU are increased by 2% compared with U-Net. They are increased by 8% and 4% compared with ReLayNet, respectively. Among them, the improvement of liquid segszmentation is particularly obvious, and the Dice coefficient is increased by 10% compared with the U-Net model.