Efficacy of the scatter correction algorithm in portable chest radiography

Portable chest radiographs (CXRs) continue to be a vital diagnostic tool for emergency and critical care medicine. The scatter correction algorithm (SCA) is a post-processing algorithm aiming to reduce scatter within portable images. This study aimed to assess whether the SCA improved image quality (IQ) in portable CXRs.

Objective and subjective IQ assessments were undertaken on both phantom and clinical images, respectively. For objective analysis, attenuators were placed on the anterior surface of the patient's thorax to simulate pathologies present within uniform regions of the phantom's lung and heart. Phantom CXRs were acquired with three different tube-current-times (mAs). Phantom images were processed with different SCA strengths. Contrast to noise ratios (CNR) within the attenuator were determined for each algorithm strength and compared to non-SCA images. For subjective analysis, two independent radiologists graded 30 clinical images with and without the SCA activated. The images were graded for IQ in different anatomical structures and overall diagnostic confidence.

Objectively, most strengths of the SCA improved the CNR in both regions. However, a detrimental effect was recorded for some algorithm strengths in regions of high contrast. Subjectively, both observers recorded the SCA significantly improved IQ in clinical CXRs in all anatomical regions. Observers indicated the greatest improvement in the lung and hilar regions, and least improvement in the chest wall and bone. All images with and without the SCA were deemed diagnostic.

This study shows the potential radiation dose neutral IQ improvement when using an SCA in clinical patient CXRs.