AUTOMATIC COMPUTERIZED RADIOGRAPHIC IDENTIFICATION OF CEPHALOMETRIC LANDMARKS

Computerized cephalometric analysis currently requires manual identifi cation of landmark locations. This process is time-consuming and limit ed in accuracy. The purpose of this study was to develop and test a no vel method for automatic computer identification of cephalometric land marks. Spatial spectroscopy (SS) is a computerized method that identif ies image structure on the basis of a convolution of the image with a set of filters followed by a decision method using statistical pattern recognition techniques, By this method, characteristic features are u sed to recognize anatomic structures. This study compared manual ident ification on a computer monitor and the SS automatic method for landma rk identification on minimum resolution images (0.16 cm(2) per pixel), Minimum resolution (defined as the lowest resolution at which a cepha lometric structure could be identified) was used to reduce computation al time and memory requirements during this development stage of the S S method, Fifteen landmarks were selected on a set of 14 test images, The results showed no statistical difference (p > 0.05) in mean landma rk identification errors between manual identification on the computer display and automatic identification using SS, We conclude that SS sh ows potential for the automatic detection of landmarks, which is an im portant step in the development of a completely automatic cephalometri c analysis.