Visual perceptual artefacts in cardiothoracic imaging: Implications for diagnostic accuracy and strategies for mitigation.

Abstract

Visual perceptual artefacts are distortions or illusions in medical image interpretation arising from the human visual system rather than hardware or imaging acquisition processes. These artefacts, emerging at various visual processing stages, such as the retina, visual pathways, visual cortex, and cognitive interpretation stages, impact the interpretation of cardiothoracic images. This review discusses artefacts including Mach bands, Dark Rim, Background Effects, Ambiguous Figures, Subjective Contours, and the Parallax Effect. A thorough literature search was conducted using PubMed and Google Scholar. Search terms included 'visual perceptual artifacts', 'cardiothoracic imaging', 'Mach bands', 'dark rim artifact', 'stress cardiac MRI', and 'radiology visual illusions'. Inclusion criteria encompassed studies focusing on visual perceptual artefacts in cardiothoracic imaging published in peer-reviewed journals. Studies not addressing visual perceptual artefacts or those focusing on imaging technology, hardware, or software-related artefacts were excluded. Duplicate studies were removed, and a final selection of 32 studies was analysed. Several key visual perceptual artefacts relevant to cardiothoracic imaging were identified. Mach bands, caused by lateral inhibition in the retina, create false contrasts at object boundaries, potentially mimicking pathologies such as fractures or pneumothoraces. The dark rim artefact observed on stress cardiac MRI, resulting from Gibbs ringing or truncation artefacts, can simulate perfusion defects and complicate diagnosis. Lateral inhibition can possibly accentuate the appearance of the dark rim artefact. Artefacts also fall under illusions of sensation, perception, and image formation. These illusions present both risks and benefits to diagnostic radiology. Recognizing visual perceptual artefacts is crucial for improving diagnostic accuracy and developing strategies to mitigate their impact. A comprehensive understanding and training on these artefacts are essential for radiologists to enhance interpretive skills, reduce diagnostic errors, and ultimately improve patient care in radiology.