Multi-planar 2.5D U-Net for image quality enhancement of dental cone-beam CT

PLoS One. 2023 May 11;18(5):e0285608. doi: 10.1371/journal.pone.0285608. eCollection 2023.

Abstract

Cone-beam computed tomography (CBCT) can provide 3D images of a targeted area with the advantage of lower dosage than multidetector computed tomography (MDCT; also simply referred to as CT). However, in CBCT, due to the cone-shaped geometry of the X-ray source and the absence of post-patient collimation, the presence of more scattering rays deteriorates the image quality compared with MDCT. CBCT is commonly used in dental clinics, and image artifacts negatively affect the radiology workflow and diagnosis. Studies have attempted to eliminate image artifacts and improve image quality; however, a vast majority of that work sacrificed structural details of the image. The current study presents a novel approach to reduce image artifacts while preserving details and sharpness in the original CBCT image for precise diagnostic purposes. We used MDCT images as reference high-quality images. Pairs of CBCT and MDCT scans were collected retrospectively at a university hospital, followed by co-registration between the CBCT and MDCT images. A contextual loss-optimized multi-planar 2.5D U-Net was proposed. Images corrected using this model were evaluated quantitatively and qualitatively by dental clinicians. The quantitative metrics showed superior quality in output images compared to the original CBCT. In the qualitative evaluation, the generated images presented significantly higher scores for artifacts, noise, resolution, and overall image quality. This proposed novel approach for noise and artifact reduction with sharpness preservation in CBCT suggests the potential of this method for diagnostic imaging.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Artifacts
  • Cone-Beam Computed Tomography / methods
  • Humans
  • Image Enhancement*
  • Image Processing, Computer-Assisted / methods
  • Imaging, Three-Dimensional* / methods
  • Phantoms, Imaging
  • Retrospective Studies

Grants and funding

Sang-Sun Han was funded by a National Research Foundation of Korea (NRF) grant funded by the Korean government (MSIT) (No. 2022R1A2B5B01002517) The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.