S G Armato1, M L Giger, H MacMahon. 1. Department of Radiology, Kurt Rossmann Laboratories for Radiologic Image Research, University of Chicago, IL 60637, USA.
Abstract
RATIONALE AND OBJECTIVES: The authors developed and tested a gray-level thresholding-based approach to automated lung segmentation in digitized posteroanterior chest radiographs. MATERIALS AND METHODS: Gray-level histogram analysis was initially performed to establish a range of thresholds for use during an iterative global gray-level thresholding technique. Local gray-level threshold analysis was then performed on the output of global thresholding. The resulting contours were subjected to several smoothing processes, including a rolling-ball technique. The final contours closely approximated the boundaries of the aerated lung regions. The method was applied to a database of 600 posteroanterior chest images. Radiologists rated the accuracy and completeness of the contours with a five-point scale. RESULTS: Results of the subjective rating evaluation indicated that this method was accurate, with 79% of the assigned ratings reflecting moderately or highly accurate segmentation and only 8% of the ratings indicating moderately or highly inaccurate segmentation. CONCLUSION: This gray-level thresholding-based approach provides accurate automated lung segmentation in digital posteroanterior chest radiographs.
RATIONALE AND OBJECTIVES: The authors developed and tested a gray-level thresholding-based approach to automated lung segmentation in digitized posteroanterior chest radiographs. MATERIALS AND METHODS: Gray-level histogram analysis was initially performed to establish a range of thresholds for use during an iterative global gray-level thresholding technique. Local gray-level threshold analysis was then performed on the output of global thresholding. The resulting contours were subjected to several smoothing processes, including a rolling-ball technique. The final contours closely approximated the boundaries of the aerated lung regions. The method was applied to a database of 600 posteroanterior chest images. Radiologists rated the accuracy and completeness of the contours with a five-point scale. RESULTS: Results of the subjective rating evaluation indicated that this method was accurate, with 79% of the assigned ratings reflecting moderately or highly accurate segmentation and only 8% of the ratings indicating moderately or highly inaccurate segmentation. CONCLUSION: This gray-level thresholding-based approach provides accurate automated lung segmentation in digital posteroanterior chest radiographs.
Authors: Yanhui Guo; Chuan Zhou; Heang-Ping Chan; Aamer Chughtai; Jun Wei; Lubomir M Hadjiiski; Ella A Kazerooni Journal: Med Phys Date: 2013-08 Impact factor: 4.071