nonvisualization

Nonvisualization is a term used to describe the absence of a perceptible image or display of a target in an imaging or data-rendering process. It indicates that no visual output has been produced despite attempts to generate one and can reflect a technical failure, an intentional non-display, or a natural absence of signal.

In medical imaging, nonvisualization describes the failure to visualize a structure or tracer uptake on modalities such as ultrasound, radiography, computed tomography, magnetic resonance imaging, or nuclear medicine scans. Causes include limitations of the equipment, operator factors, patient-related issues (such as body habitus or movement), timing, or true absence of the target. Nonvisualization can reduce diagnostic yield and may lead to repeat studies, alternative imaging modalities, or additional tests.

In data visualization and information design, nonvisualization may refer to data that is not represented graphically or to interfaces that do not render information in a visual form. This can result from design choices, data constraints, or accessibility considerations. Discussions of nonvisualization also address making information accessible to users who rely on non-visual modalities.

Overall, nonvisualization is a descriptive term rather than a diagnosis. It highlights the absence of a visual representation and emphasizes the need to assess technique, signal, and the underlying data or anatomy, often guiding subsequent steps to obtain visualization or to explain why it is not feasible. See also visualization, image quality, diagnostic imaging, data visualization, and accessibility.