Explainable fully automated CT scoring of interstitial lung disease for patients suspected of systemic sclerosis by cascaded regression neural networks and its comparison with experts.

Journal: Scientific reports
PMID:

Abstract

Visual scoring of interstitial lung disease in systemic sclerosis (SSc-ILD) from CT scans is laborious, subjective and time-consuming. This study aims to develop a deep learning framework to automate SSc-ILD scoring. The automated framework is a cascade of two neural networks. The first network selects the craniocaudal positions of the five scoring levels. Subsequently, for each level, the second network estimates the ratio of three patterns to the total lung area: the total extent of disease (TOT), ground glass (GG) and reticulation (RET). To overcome the score imbalance in the second network, we propose a method to augment the training dataset with synthetic data. To explain the network's output, a heat map method is introduced to highlight the candidate interstitial lung disease regions. The explainability of heat maps was evaluated by two human experts and a quantitative method that uses the heat map to produce the score. The results show that our framework achieved a of 0.66, 0.58, and 0.65, for the TOT, GG and RET scoring, respectively. Both experts agreed with the heat maps in 91%, 90% and 80% of cases, respectively. Therefore, it is feasible to develop a framework for automated SSc-ILD scoring, which performs competitively with human experts and provides high-quality explanations using heat maps. Confirming the model's generalizability is needed in future studies.

Authors

  • Jingnan Jia
    Division of Image Processing, Department of Radiology, Leiden University Medical Center, PO Box 9600, 2300 RC, Leiden, The Netherlands. Electronic address: j.jia@lumc.nl.
  • Irene Hernández-Girón
    Division of Image Processing, Department of Radiology, Leiden University Medical Center (LUMC), P.O. Box 9600, 2300, RC Leiden, The Netherlands.
  • Anne A Schouffoer
    Department of Rheumatology, Leiden University Medical Center, PO Box 9600, 2300 RC, Leiden, The Netherlands. Electronic address: A.A.Schouffoer@lumc.nl.
  • Jeska K de Vries-Bouwstra
    Department of Rheumatology, Leiden University Medical Center, PO Box 9600, 2300 RC, Leiden, The Netherlands. Electronic address: j.k.de_vries-bouwstra@lumc.nl.
  • Maarten K Ninaber
    Department of Pulmonology, Leiden University Medical Center, PO Box 9600, 2300 RC, Leiden, The Netherlands. Electronic address: M.K.Ninaber@lumc.nl.
  • Julie C Korving
    Department of Radiology, Leiden University Medical Center (LUMC), P.O. Box 9600, 2300, RC Leiden, The Netherlands.
  • Marius Staring
    Division of Image Processing, Department of Radiology, Leiden University Medical Center, Leiden PO Box 9600, 2300 RC, The Netherlands.
  • Lucia J M Kroft
    Department of Radiology, Leiden University Medical Center, PO Box 9600, 2300 RC, Leiden, The Netherlands. Electronic address: L.J.M.Kroft@lumc.nl.
  • Berend C Stoel
    Division of Image Processing, Department of Radiology, Leiden University Medical Center, Leiden, the Netherlands. Electronic address: b.c.stoel@lumc.nl.