Validation of optical three-dimensional plagiocephalometry by computed tomography, direct measurement, and indirect measurements using thermoplastic bands.

The aim of the study was to validate optical three-dimensional surface imaging for plagiocephalometry by comparing it with established direct and indirect plagiocephalometric measurements. From head models with symmetric and asymmetric shapes, a number of distances were determined for plagiocephalometry. Data were acquired by optical three-dimensional surface imaging, direct and indirect measurements, and computed tomography. Data acquisition was repeated 10 times with each method. In 10 patients with positional plagiocephaly, optical three-dimensional surface data were acquired, and thermoplastic strips were used to reproduce the largest circumferences of the patients' heads. All measurements were carried out by the same observer. The measurements for the head models were used to assess the reproducibility of the different measurement techniques and to check if there were statistically significant differences between them. The patient measurements were also used to determine if there were statistically significant differences between the different techniques in clinical use. None of the plagiocephalometric distances showed statistically significant differences when the 4 different methods were compared on the head models (P > 0.05). Comparison of plagiocephalometric distances obtained from optical three-dimensional imaging and from thermoplastic strips in clinical use showed also no significant difference (P > 0.05). The results of the current study reveal that optical three-dimensional imaging is a relevant alternative to other established techniques in plagiocephalometry that should be tested in larger patient series.