Revisiting Dynamic Range and Image Enhancement Ability of Contemporary Digital Radiographic Systems-Part 2: a Subjective Assessment.

Objective: To assess the subjective image quality of original and manually enhanced radio-graphs acquired at different X -ray exposure times and using different digital systems. Methods: A total of 500 radiographs obtained under 10 exposure times, 5 digital systems, and 2 enhancement conditions were assessed by 5 observers, who were asked to categorize each radiograph into acceptable or unacceptable. A radiograph was considered to be accept-able when at least four out of five observers found it acceptable. Descriptive analysis was used to summarize the outcomes and compare the subjective image quality of original and manu-ally enhanced digital radiographs among different X -ray exposure times and digital systems. Results: Express had six exposure times producing acceptable original images within a range from 0.063 to 0.4 s, followed by Digora Toto, which had five within a range from 0.063 to 0.32 s, Digora Optime, which had four within a range from 0.063 to 0.2 s,and SnapShot and VistaScan, which had 2 (0.2 and 0.32 s) and 1 (0.63 s), respectively. Image enhancement turned unacceptable images into acceptable ones in four digital systems: SnapShot at three exposure times, Digora Toto at two exposure times, Express at one exposure time, and VistaScan at four exposure times. Conclusion: Image enhancement based on brightness and/or contrast adjustments may be necessary to reveal the useful dynamic range of some digital radiographic systems and PSP-based systems may not necessarily have a wider range than sensor -based systems. Dentomaxillofacial Radiology (2023) 52, 20220370. doi: 10.1259/dmfr.20220370