Visual search in chest radiology: definition of reference anatomy for analysing visual search patterns

The role of eye movements in medical image understanding has been extensively studied. To assess the visual search behaviour of observers in examining images from different patients, it is necessary to account for patient-specific morphological variations, such that fixations related to specific feature landmarks are co-registered. This paper proposes a framework for analysing the spatial dynamics of the eye movements through the introduction of standardised lung anatomy. The reference lungs have been obtained by using hierarchical free-form registration of high resolution computed tomography (HRCT) lung images. The registration procedure is used to map patient-specific gaze points to the reference anatomy such that the general visual behaviour of different observers can be assessed.