Accuracy of diagnosis of subtle chest disease and subtle fractures with a teleradiology system

OBJECTIVE. This study compared conventional thoracic and skeletal radiographs with 12-bit digitized images of the same radiographs in terms of subjective image quality and accuracy of diagnosis of subtle disease. MATERIALS AND METHODS. Thirty-six chest radiographs with normal findings, 48 chest radiographs with abnormal findings, 29 skeletal radiographs with normal findings, and 26 skeletal radiographs with abnormal findings were included in this study. The images were chosen for the subtlety of their findings (nodules, pneumothoraces, interstitial lung disease, fractures). Each set of images was laser-digitized and viewed independently by three radiologists at a teleradiology workstation with a 1280 x 1024 pixel matrix monitor equipped with an eight-bit-per-pixel gray-scale display. All images were viewed at maximum resolution. After review of the digitized images for image quality and for the presence of abnormalities, each radiologist analyzed the analog images in a similar way. RESULTS. Sensitivities for detecting nodules, pneumothoraces, and interstitial lung disease on digitized chest radiographs were 58%, 75%, and 90%, respectively, compared with 62%, 79%, and 92%, respectively, on the original radiographs. Sensitivity for fracture detection on digitized bone radiographs was 87% compared with 88% on analog radiographs. None of these differences was statistically significant. CONCLUSION. Digitization of radiographs for primary diagnosis by teleradiology results in a slight decrease in sensitivity for detection of subtle abnormalities, provided that the images are viewed at maximum resolution.