Spontaneous changes of skull morphology in premature babies: A preliminary study using plagiocephalometric analysis

Aim — to develop a reliable protocol to study the spontaneous changes in te skull morphology, specifically plagiocephaly in premature infants.Materials and methods. Evaluation of the degree of asymmetry using a plagiocephalometric tool and passive motion assessment for axial rotation and clinical examination of the neck muscles in six preterm infants. All measures are taken four times over a two months period.Results. About the placement of thermoplastic bands, a maximal variability of 3 % and 5 % was found for intra-and inter- observations respectively for the indices of interest (ODDI, CPI, CVAI). The variability of measures taken on photocopies was less than 1 %. 67 % of children had a preferential position on the third measure (T3) and 83 % on the fourth measure (T4). The prevalence of plagiocephaly was 17, 67, 33 and 50 % at T1, T2, T3 and T4 respectively considering a threshold of oblique diameters difference (ODDI) of 104 % . No influence of gender, gestational age, primiparity or asymmetry in muscle tension and/or rotation has been highlighted. In comparison with previous data, a very highly significant difference (p=0,001) was found for the index head values.Conclusion. This study has demonstrated the feasibility of the method. More consistent data should be considered, with a broader sample in order to provide a relevant analysis of the morphometric changes of the skull base. According to the criteria of the literature, three premature infants out of six had a plagiocephaly at T4 and we observed a normalization of morphometric values was observed in two infants.