Acoustical markers for CAD-detected pulmonary nodules in chest CT: A way to avoid suggestion and distraction of radiologist's attention?

Purpose: To compare the influence of visual and acoustical CAD markers on radiologist’s performance with regard to suggestive and distractive effects. Materials and methods: Ten radiologists analyzed 150 pictures of ches t CT slices. Every picture contained a visual CAD marker. 100 pictures showed one nodule: CAD marker marked this in 50 cases and in 50 cases a false positive finding (f.p.). The other 50 cases showed no nodule but an f.p. marker. After 3 years same images were presented to thirteen radiologists with only a sound as CAD marker. 55 of 150 images were marked, 30 true positive and 25 f.p. Sensitivity and f.p. rate were calculated for both marker ty pes. Significance between sens itivities and f.p. rates were calculated by multiple-ana lysis-of-variance (MANOVA). Results: Without CAD mean sensitivity resp. f.p. were 57.7% /.13 . In case of correct optical resp. acoustical marker sensitivity increased to 75.6% resp. 63.1%. For incorrect se t marker mean f.p. rate increased to .31 resp. .24. MANOVA showed that marker’s correctness highly significan tly influenced sensitivity (p