Visual cues in the interpretation of medical images

The use of the computer in imaging has provided great versatility for the display of medical image information. In order to be useful in a medical sense, the display must be perceptually acceptable to the human observer, who must be able to extract the relevant diagnostic information from the image. Diagnostic information is defined by the imaging task, and the concept of task-dependent image quality is, therefore, very important. Visualization and estimation tasks may require different visual cues for their performance. Visualization tasks require strong boundary cues, whereas intensity estimation tasks require texture cues. Both tasks can be aided by appropriate image displays. Color can be helpful in estimation tasks, and three-dimensional display can aid visualization tasks. No matter what the task or the image, as long as an observer is needed to read out the information, performance is the final arbiter of the goodness of the image.