Three-Dimensional Anthropometry for Evaluating Reliability of Worm's Eye View Photographs of Unilateral Cleft Lip Nasal Deformity

Abstract

Background: Worm's eye view photograph has been widely used for anthropometric analysis. However, it is difficult to secure objectivity because it cannot be captured at a constant head-up degree. This study aimed to analyze whether anthropometric nasal measurements in worm's eye view differ from the actual values. Methods: A total of 40 patients with unilateral cleft lip nasal deformities were included. The 30 degrees and 60 degrees head-tilted two-dimensional (2D) photographs were captured from the three-dimensional (3D) images. The real measurements were obtained from 3D images and 2D measurements were obtained from the captured images. The cleft/non-cleft side ratios of the nostril height, width, and alar base width were compared between 3D and 2D images. Results: There was a significant difference in the nostril height between the 3D and 30 degrees values (3D = 0.82, 30 degrees = 0.92, P < 0.001) but no meaningful difference was noted between the 3D and 60 degrees values (3D = 0.82, 60 degrees = 0.84, P = 0.31). There was no significant difference in the nostril width among the 30 degrees, 60 degrees, and 3D values. A significant difference was found in the alar base width between the 3D values and both the 30 degrees (3D = 0.998, 30 degrees = 1.04, P = 0.026) and 60 degrees (3D = 0.998, 30 degrees = 1.03, P = 0.029) values. Conclusions: This study demonstrates that 2D photographs do not accurately reflect actual values. The nostril height and alar width ratio can be changed depending on the head-up position. The 3D systems are more accurate and less affected by the subject's head position. Therefore, the 3D imaging system is advocated for the anthropometric analysis of unilateral cleft lip nasal deformity.