The validation of 3D spiral CT-based measurements of simulated maxillofacial neoplasms

Objective. The purpose of this study was to determine the precision and acc uracy of 3-dimensional spiral computed tomography-based linear measurements of neoplasms associated with the mandible. Study design. Four cadaver heads, each with 2 simulated tumors made of clay , containing contrast medium, and positioned medial to the mandible, were e xamined by means of a subsecond spiral computed tomography unit. The comput ed tomography data were transferred to a computer workstation and analyzed through use of 3-dimensional reconstructed images. Linear measurements of t he length, width, and depth of the simulated tumors were made by 2 observer s, twice each. The soft tissues were then removed and the same measurements made by means of calipers. Results. There were no statistically significant differences between the 3- dimensional computed tomography and physical measurements (P > .05). The me an difference was found to be less than 0.4 mm. Conclusions. Spiral computed tomography imaging allows for precise and accu rate 3-dimensional computed tomography based measurements for neoplastic le sions in the mandible.