RSNA 2003 

Abstract Archives of the RSNA, 2003


K19-1023

Usefulness of Advanced Computer-aided Diagnostic Scheme for Lung Cancer Diagnosis in Chest Radiographs: Observer Performance Study

Scientific Papers

Presented on December 3, 2003
Presented as part of K19: Physics (Image Processing: CAD V--Lung)

Participants

Junji Shiraishi PhD, PRESENTER: Nothing to Disclose

Abstract: HTML Purpose: To develop an advanced computer-aided diagnostic (CAD) scheme for lung cancer diagnosis in chest radiographs and evaluate the scheme with an observer performance study. Methods and Materials: The advanced CAD scheme consisted of two major components, one for detection of lung nodules, and another for distinguishing lung cancers from computer false positives and benign nodules. The CAD output was indicated by color-coded arrows which indicated both computer detection results of suspicious nodules, and computer-estimated likelihood of malignancy. In addition, the CAD scheme allowed to provide computer-estimated likelihood of malignancy for potential lesions interactively, if the radiologist indicated any suspected areas on chest radiographs. Receiver operating characteristic (ROC) analysis for detecting lung cancers was performed without and with CAD output; radiologists were asked to indicate the likelihood of malignancy for the case, as well as the location of most suspicious area for lung cancer. Our database included 150 chest radiographs with 72 confirmed solitary lung cancers, 36 confirmed solitary benign nodules, and 42 normal cases, which were used for evaluation of the CAD scheme. For the observer performance study, 48 of these chest radiographs were used, with the same balance of cancer and other cases. Twelve radiologists participated in this ROC study. Monochrome and color LCD monitors, each with an active area of 408 mm x 306 mm (1600 x 1200 pixels), were used for displaying the original image and the image with CAD output, respectively. Results: The CAD scheme achieved a performance of 81.4 % sensitivity with 1.2 false positives per image for detection of lung nodules, and an area under the ROC curve (Az) of 0.863 for distinction of lung cancers from other computer-detected false positives and benign nodules. The average Az values for radiologists without and with CAD output were 0.800 and 0.753, respectively. The performance of radiologists was improved significantly when this advanced CAD scheme was used (P = 0.008). LROC curves for all observers with CAD output were also improved from those obtained without CAD output. Conclusion: This advanced CAD scheme including detection and classification of lung cancers would be useful in improving the performance of radiologists for detecting lung cancers on chest radiographs. (K.D. is a shareholder in R2 Technology, Inc. and Deus Technology, Inc. This work is supported by USPHS Grant CA62625.) Questions about this event email: junji@uchicago.edu

Cite This Abstract

Shiraishi PhD, J, Usefulness of Advanced Computer-aided Diagnostic Scheme for Lung Cancer Diagnosis in Chest Radiographs: Observer Performance Study.  Radiological Society of North America 2003 Scientific Assembly and Annual Meeting, November 30 - December 5, 2003 ,Chicago IL. http://archive.rsna.org/2003/3101054.html