Attention and medical diagnosis

When a radiologist is presented with a medical image, be it a radiograph or the many hundreds of images generated from a computerized tomography (CT) or magnetic resonance imaging (MRI) scanner, he or she needs to make sense of the images, which are representations of the human body, and perceive pathology among the different ambiguous shapes, shades and contours. Abnormalities are normally perceived quickly, as eye tracking has demonstrated, with pathology usually looked at within the first two or three fixations. It takes many cases and years of training to become proficient in interpreting medical images as perceptual discrimination is learned and acquired knowledge is converted into a variety of cognitive strategies and cognitive skills. This process is still not fully understood, but it seems practice with feedback is the only way to achieve clinically acceptable performance. Medical imaging has seen many developments in equipment, including the recent move away from film to digital technologies. Research has, however, demonstrated that error rates during the past 50 years remain resistant to these improvements and changes in technology. This demonstrates the importance of perceptual and cognitive factors in the performance of radiologists when interpreting medical images. This entry discusses eye movements, models of medical image perception, searching medical images, and decision processes.