Three-dimensional analysis of cranial and facial asymmetry after helmet therapy for positional plagiocephaly.

Abstract

Helmet therapy is a non-surgical option for treating positional plagiocephaly, and its effectiveness has been validated by various researches. In addition to cranial flattening and asymmetry, ipsilateral prominence of the mid-face and relative anterior transposition of the ipsilateral ear is also common. Hence, we investigated the impact of helmet therapy on mid-facial asymmetry. Ninety-nine patients diagnosed with positional plagiocephaly and treated by helmet therapy between September 2005 and July 2012 were enrolled. Therapy was initiated at various ages: group I, <6months (n = 35); group II, 6months to 1year (n = 43); group III, >1year (n = 21). A cranial vault asymmetry index was measured at the levels of the inferior orbital rim (CVAIIOR-MF) and superior orbital rim (CVAISOR-LC) and midway from the superior orbital rim to the vertex (CVAIMID-UC). Anterior transposition of the ipsilateral ear was verified by measuring the distance (D EAR) between the actual position of the ear and its expected position relative to the contralateral ear. All variables were compared before and after helmet therapy and were categorized by age at treatment initiation. CVAIIOR-MF and CVAISOR-LC were lower in all three age groups after helmet therapy, confirming therapeutic efficacy. CVAIMID-UC (upper level cranial asymmetry) and D EAR (mid-facial soft tissue asymmetry) also improved significantly in groups I and II which were younger than 1year old. In positional plagiocephaly, helmet therapy is effective in correcting both cranial and mid-facial asymmetries. Outcomes were optimal in patients <1year of age, but older patients also showed some improvement.