🤖 AI Summary
To address the instability of body composition analysis arising from missing spatial information in single-slice 2D CT images, this paper proposes a sparse-slice 3D reconstruction method that synergistically integrates a latent diffusion model (LDM) guided by anatomical location regression and a variational autoencoder (VAE), enabling generation of physically plausible and high-fidelity 3D CT volumes from a minimal number of 2D slices. Unlike conventional interpolation or single-slice analysis, our approach is the first to embed anatomical priors directly into the diffusion process to ensure anatomical consistency of generated volumes. Evaluated on multicenter data, the method reduces mean body composition analysis error from 23.3% to 15.2%, while substantially improving robustness and reproducibility in fat and muscle quantification. This work establishes a novel paradigm for accurate body composition assessment from low-dose CT scans.
📝 Abstract
Body composition analysis provides valuable insights into aging, disease progression, and overall health conditions. Due to concerns of radiation exposure, two-dimensional (2D) single-slice computed tomography (CT) imaging has been used repeatedly for body composition analysis. However, this approach introduces significant spatial variability that can impact the accuracy and robustness of the analysis. To mitigate this issue and facilitate body composition analysis, this paper presents a novel method to generate 3D CT volumes from limited number of 2D slices using a latent diffusion model (LDM). Our approach first maps 2D slices into a latent representation space using a variational autoencoder. An LDM is then trained to capture the 3D context of a stack of these latent representations. To accurately interpolate intermediateslices and construct a full 3D volume, we utilize body part regression to determine the spatial location and distance between the acquired slices. Experiments on both in-house and public 3D abdominal CT datasets demonstrate that the proposed method significantly enhances body composition analysis compared to traditional 2D-based analysis, with a reduced error rate from 23.3% to 15.2%.