High-angular resolution diffusion imaging generation using 3d u-net

Neuroradiology. 2024 Mar;66(3):371-387. doi: 10.1007/s00234-024-03282-6. Epub 2024 Jan 18.

Abstract

Purpose: To investigate the effects on tractography of artificial intelligence-based prediction of motion-probing gradients (MPGs) in diffusion-weighted imaging (DWI).

Methods: The 251 participants in this study were patients with brain tumors or epileptic seizures who underwent MRI to depict tractography. DWI was performed with 64 MPG directions and b = 0 s/mm2 images. The dataset was divided into a training set of 191 (mean age 45.7 [± 19.1] years), a validation set of 30 (mean age 41.6 [± 19.1] years), and a test set of 30 (mean age 49.6 [± 18.3] years) patients. Supervised training of a convolutional neural network was performed using b = 0 images and the first 32 axes of MPG images as the input data and the second 32 axes as the reference data. The trained model was applied to the test data, and tractography was performed using (a) input data only; (b) input plus prediction data; and (c) b = 0 images and the 64 MPG data (as a reference).

Results: In Q-ball imaging tractography, the average dice similarity coefficient (DSC) of the input plus prediction data was 0.715 (± 0.064), which was significantly higher than that of the input data alone (0.697 [± 0.070]) (p < 0.05). In generalized q-sampling imaging tractography, the average DSC of the input plus prediction data was 0.769 (± 0.091), which was also significantly higher than that of the input data alone (0.738 [± 0.118]) (p < 0.01).

Conclusion: Diffusion tractography is improved by adding predicted MPG images generated by an artificial intelligence model.

Keywords: Artificial intelligence; Diffusion-weighted imaging; High angular resolution diffusion imaging; Orientation distribution function; Tractography.

MeSH terms

  • Adult
  • Artificial Intelligence*
  • Diffusion Magnetic Resonance Imaging* / methods
  • Diffusion Tensor Imaging / methods
  • Humans
  • Image Processing, Computer-Assisted / methods
  • Magnetic Resonance Imaging
  • Middle Aged
  • Neural Networks, Computer