Evaluation of the laser scanner as a surface measuring tool and its accuracy compared with direct facial anthropometric measurements.

The development of new laser scanning techniques enabling the capture of 3-D images which can be quantitatively assessed permits their use for surface measurements of the face. We used a laser optical surface scanner to study 30 subjects and took 83 facial anthropometric measurements, using 41 identifiable landmarks on the scanned image. These were compared to the standard anthropometric measurements using the same landmarks. Of these, 12 (14.0%) showed a mean difference less than 1.0 mm and were considered highly reliable measurements and 16 (19.0%) with less than 1.5 mm difference were considered reliable. The highly reliable measurements were mainly in the nasal and circumoral regions and the landmarks involved were mainly those in the mid-saggital plane. This indicates that the laser scanner can be a useful tool for rapid facial measurements in selected anatomical parts of the face. Accurate location of landmarks and operator skill are important factors to achieve reliable results.