Changes in Cranial Shape and Developmental Quotient at 6 Months of Age in Preterm Infants.

The purpose of this study was to investigate changes in cranial shape among preterm neonates aged 1-6 months and the relationship between developmental quotient (DQ) and cranial shape at 6 months of age. Preterm infants who were hospitalized in our hospital were prospectively followed for 6 months. The cephalic index (CI) and cranial vault asymmetry index (CVAI) were evaluated at 1 (T1), 3 (T2), and 6 months (T3) of age and compared with those of the full-term infants. The relationship between CI or CVAI and DQ at T3 was analyzed using the Enjoji Scale of Infant Analytical Development. A total of 26 participants born at 34.7 ± 1.9 weeks of gestation were included. The CI increased with age (T1: 77.2%, T2: 82.9%, T3: 85.4%, p < 0.01). The prevalence of dolichocephaly at T3 did not significantly differ from that in full-term infants (15.4% vs. 4.5%, p = 0.08). CVAI did not significantly differ between preterm and full-term infants. The DQ showed no significant correlation with either the CI or CVAI (correlation coefficients: 0.23 for CI, -0.01; CVAI). Dolichocephaly improved over time in preterm infants and no relationship between cranial shape and development was observed in preterm infants at 6 months of age.

Cranial Shape Measurements Obtained Using a Caliper and Elastic Bands Are Useful for Brachycephaly and Deformational Plagiocephaly Screening.

We assessed a method for screening the cranial shape of 1-month-old infants using a simple measuring instrument instead of a three-dimensional scanner. The Mimos craniometer was used to measure cranial length, cranial width, and two diagonal lengths to calculate the cranial index (CI) and cranial asymmetry (CA). We defined a CI > 90% as brachycephaly and CA > 5 mm as deformational plagiocephaly (DP). Intra- and inter-examiner accuracy analyses were performed on a dummy doll and 1-month-old infants. The measurements of healthy 1-month-old infants were compared with previously reported three-dimensional scanner measurements. Intra- and inter-rater measurements showed good accuracy; diagnostic accuracy comparisons of brachycephaly and DP using a three-dimensional scanner showed kappa values of 1.0 and 0.8, respectively. Comparisons were made among 113 infants matched for day-age at the date of measurement; there were no significant differences in the CI (85.0% vs. 85.2%, p = 0.98) and CA (5.9 mm vs. 6.0 mm, p = 0.48) between the scanner and caliper measurements, nor in the prevalence of brachycephaly (12.4% vs. 17.7%, p = 0.35) or DP (58.4% vs. 56.6%, p = 0.89). This simple measurement method using calipers and bands was useful in screening for brachycephaly and DP in 1-month-old infants.