Quantified comparison of frontal sinus patterns by means of computed tomography.

The observation of frontal sinus patterning is a well-established technique of personal identification in forensic anthropology. Variations in size, shape, symmetry, border outline, and the presence and number of septa and cells are compared using antemortem and postmortem radiographs. Traditionally, a standard frontal view is utilized. Computed tomography produces contiguous radiographic images of the cranium at predetermined increments. Multiple comparisons of the sinus configuration can therefore be made at different levels. The use of different 'window' settings (attenuation coefficient ranges) for the production of CT scans is discussed. A scoring system is described for the precise and quantified comparison of frontal sinuses in antemortem to postmortem CT scans. The application of these procedures to actual cases is described.