The three-dimensional course of cranial development of very preterm infants during the first year of life

Background: Cranial measurements are crucial for evaluating preterm general development because they are a surrogate tool for evaluating brain growth. Usually, they are based on tape-measured head circumference; however, a three-dimensional (3D) approach expands the diagnostic spectrum to the evaluation of cranial volume and shape.

Aims: Very preterm (vPT) infants face multiple risks and obstacles in their early development. In this study, we analyze the risk for cranial anomalies of vPT compared with term-born (TB) infants during the first year of life.

Study design and subjects: In this single-centre prospective cohort study, 23 vPT and 24 TB healthy infants were assessed. At term equivalent age (TEA) of vPT and time of birth of TB, and 1, 3, 6 and 12 months of postmenstrual age, respectively, a 3D head scan was performed and cephalometrically evaluated regarding cranial growth (head circumference, cranial volume) and shape.

Results: Head circumference and cranial volume showed a similar course in vPT and TB. Cranial shape differed significantly between vPT and TB. At TEA, vPT showed longer and narrower heads (dolichocephaly), a difference that disappeared around the 6th month of life. Presence of plagiocephaly was initially similar in vPT and TB, with an increasing difference between both groups with a peak at six months when 34.8 % of the vPT versus none of the TB showed a moderate to severe plagiocephaly (p = 0.004). In vPT, cranial volume significantly correlated with cranial shape, whereas dolichocephaly at TEA had no influence on the further course of plagiocephaly.

Conclusion: Cranial development of vPT follows a different course than of TB in terms of cranial shape anomalies, while cranial growth remains unaffected. German Clinical Trials Register number: DRKS00022558.