Head shape at age 36 months among children with and without a history of positional skull deformation

OBJECTIVEIn this study, the authors examined head shape through age 36 months for children with and without a history of positional plagiocephaly and/or brachycephaly (PPB).METHODSInfants with PPB (cases) were identified through a craniofacial clinic at the time of diagnosis. Infants without diagnosed PPB were identified through a participant registry. Clinician ratings of 3D cranial images were used to confirm the presence or absence of PPB. The cohort included 235 case infants (diagnosed PPB, confirmed with 3D imaging), 167 unaffected controls (no diagnosed PPB, no deformation detected), and 70 affected controls (no diagnosed PPB, discernible skull deformation). Participants were seen in infancy (age 7 months, on average) and again at ages 18 and 36 months. At each visit, automated 3D measures of skull deformation quantified posterior flattening and generated an absolute asymmetry score. The authors also used automated 2D measures to approximate overall asymmetry (approximate oblique cranial length rati...