Optimized 3D coordinate reconstruction from paired stereographs using a calibrated phantom.
A refinement to a previously described three-dimensional reconstruction algorithm based on point identification in calibrated non-orthogonal radiograms (stereo-pairs) is described. The modification involves a computation of the focal point magnitude of the point in three dimensions, analogous to focusing in two dimensions, as well as the most likely location of the target point in 3-space; the focal point magnitude may be thought of as the precision of the point identification. Multiple observer studies of the same stereopair can be used to estimate three-dimensional reconstruction accuracy by providing an average location and a mean distance from average. Both measures are useful parameters for initial selection of bone landmark references and for error propagation studies.
Small
C F
CF
Clinical Mechanics Group, Queen's University, Kingston, Ontario, Canada.
Bryant
J T
JT
D000465:Algorithms; D002138:Calibration; D007091:Image Processing, Computer-Assisted; D008961:Models, Structural; D015588:Observer Variation; D011859:Radiography / Q000379:methods*; D012985:Software Design