Enhancing recognition of lesions in radiographic images using perceptual feedback

When radiologists search a medical x-ray image for an abnormality, their eyes often fixate and refixate the true target, dwelling on it for prolonged times, often without recognizing that they have discovered the object of search. Monitoring the eye position of the radiologist provides the x and y coordinates of the dwelling location. This location can be superimposed on the image and dynamically fed back to the radiologist for reevaluation. When this is done, the probability of recognizing and reporting an abnormality is shown to be enhanced significantly. An increase of 20% in observer performance is observed for radiologists searching chest images for tumors after receiving perceptual feedback compared to a second look without perceptual feedback. The true-positive rate increased and the false-positive rate decreased. Perceptual feedback represents a potentially significant technique for enhancing lesion recognition in radiology. (C) 1998 society of Photo-Optical Instrumentation Engineers. [S0091-3286(98)00203-7].