Image Reject Patterns in Computed Radiography: Insights From a Ghanaian Radiology Department

Image reject analysis is a critical quality assurance (QA) tool in diagnostic imaging, helping to minimise unnecessary radiation exposure and improve imaging efficiency. This study evaluates image rejection patterns in a computed radiography (CR) system at a major tertiary teaching hospital in Ghana, identifying key sources of errors and their implications for radiology practice.

A retrospective review of radiographic images acquired between April and June 2023 was conducted. Images, including those flagged as rejects were retrieved from the CR system and analysed for rejection rates, trends by anatomical region, and key error sources.

Of the 5889 images reviewed, 974 were rejected, resulting in an overall rejection rate of 16.5%. Rejection rates varied considerably across anatomical regions. High rejection rates were observed in skull/sinus (34.9%, n = 90/258), pelvic (29.9%, n = 88/294) and abdomen (26.9%, n = 84/312) examinations. Low rejects were recorded for ankle (1.8%, n = 2/110), humerus (2.4%, n = 2/82), forearm (6.7%, n = 6/90), elbow (9.7%, n = 6/62), and lower leg (7.5%, n = 16/214). Across all examinations, the three leading causes of image rejection were anatomical cut-off (40.5%, n = 394), positioning errors (27.5%, n = 268), and beam centering errors (18.5%, n = 180). Less frequent causes included exposure-related issues (6.6%, n = 64), patient movement (2.9%, n = 28), and artefacts or ghosting (4.1%, n = 40).

This study reinforces the role of image reject analysis as a valuable QA measure in CR systems. The high rejection rates observed highlight the need for targeted interventions in positioning, workflow optimization, and radiographer training, particularly in resource-constrained settings to enhance diagnostic quality and patient safety.