Automatic rib detection in chest radiographs

Abstract

A detailed algorithm is presented for automatic detection of posterior (dorsal) ribs in posterior/anterior chest radiographs. It is entirely automatic and includes algorithms for locating the lung fields and the lung boundary. Written in PL/I for an IBM 3031, it requires about 8 sec to process a 400 × 400 digitized full chest radiograph which is significantly faster than previously published results. The reason for the efficiency can be attributed to the fact that no two-dimensional image processing is performed; it works instead by locating the ribs on a small set of one-dimensional sections taken through the lung fields. Curves are then fitted through these locations to represent the rib edges. The detection of anterior (ventral) ribs is also discussed. © 1983.