Slice Imputation: Intermediate Slice Interpolation for Anisotropic 3D Medical Image Segmentation
This addresses the challenge of anisotropic resolution in medical imaging for clinicians and researchers, though it appears incremental as it builds on prior slice imputation methods.
The paper tackles the problem of anisotropic 3D medical image segmentation by introducing a slice imputation method that improves smoothness in all three directions, resulting in better segmentation performance across multiple medical imaging tasks.
We introduce a novel frame-interpolation-based method for slice imputation to improve segmentation accuracy for anisotropic 3D medical images, in which the number of slices and their corresponding segmentation labels can be increased between two consecutive slices in anisotropic 3D medical volumes. Unlike previous inter-slice imputation methods, which only focus on the smoothness in the axial direction, this study aims to improve the smoothness of the interpolated 3D medical volumes in all three directions: axial, sagittal, and coronal. The proposed multitask inter-slice imputation method, in particular, incorporates a smoothness loss function to evaluate the smoothness of the interpolated 3D medical volumes in the through-plane direction (sagittal and coronal). It not only improves the resolution of the interpolated 3D medical volumes in the through-plane direction but also transforms them into isotropic representations, which leads to better segmentation performances. Experiments on whole tumor segmentation in the brain, liver tumor segmentation, and prostate segmentation indicate that our method outperforms the competing slice imputation methods on both computed tomography and magnetic resonance images volumes in most cases.