Comparison of Deep-Learning Image Reconstruction With Hybrid Iterative Reconstruction for Evaluating Lung Nodules With High-Resolution Computed Tomography

J Comput Assist Tomogr. 2023 Jul-Aug;47(4):583-589. doi: 10.1097/RCT.0000000000001460. Epub 2023 Mar 3.

Abstract

Objective: This study aimed to investigate the impact of deep-learning reconstruction (DLR) on the detailed evaluation of solitary lung nodule using high-resolution computed tomography (HRCT) compared with hybrid iterative reconstruction (hybrid IR).

Methods: This retrospective study was approved by our institutional review board and included 68 consecutive patients (mean ± SD age, 70.1 ± 12.0 years; 37 men and 31 women) who underwent computed tomography between November 2021 and February 2022. High-resolution computed tomography images with a targeted field of view of the unilateral lung were reconstructed using filtered back projection, hybrid IR, and DLR, which is commercially available. Objective image noise was measured by placing the regions of interest on the skeletal muscle and recording the SD of the computed tomography attenuation. Subjective image analyses were performed by 2 blinded radiologists taking into consideration the subjective noise, artifacts, depictions of small structures and nodule rims, and the overall image quality. In subjective analyses, filtered back projection images were used as controls. Data were compared between DLR and hybrid IR using the paired t test and Wilcoxon signed-rank sum test.

Results: Objective image noise in DLR (32.7 ± 4.2) was significantly reduced compared with hybrid IR (35.3 ± 4.4) ( P < 0.0001). According to both readers, significant improvements in subjective image noise, artifacts, depictions of small structures and nodule rims, and overall image quality were observed in images derived from DLR compared with those from hybrid IR ( P < 0.0001 for all).

Conclusions: Deep-learning reconstruction provides a better high-resolution computed tomography image with improved quality compared with hybrid IR.

MeSH terms

  • Aged
  • Aged, 80 and over
  • Algorithms
  • Deep Learning*
  • Female
  • Humans
  • Image Processing, Computer-Assisted / methods
  • Lung
  • Male
  • Middle Aged
  • Radiation Dosage
  • Radiographic Image Interpretation, Computer-Assisted / methods
  • Retrospective Studies
  • Tomography, X-Ray Computed / methods