Natural-Course Evaluation of Infants with Positional Severe Plagiocephaly Using a Three-Dimensional Scanner in Japan: Comparison with Those Who Received Cranial Helmet Therapy

Abstract

This study aimed to clarify the natural course of positional plagiocephaly using a three-dimensional (3D) scanner and investigate the effectiveness of cranial helmet therapy (CHT). One hundred infants with severe plagiocephaly who visited our institutions between April 2020 and March 2021 were included. Cranial shape was measured using an Artec Eva 3D scanner. A cranial asymmetry (CA) >12 mm was diagnosed as severe plagiocephaly. An infant whose CA subsided to <12 mm was considered to have improved naturally or by CHT. The difference in CA between the second and initial scans was defined as the improvement value (median scan interval was two months). In the natural-course group comprising 56 infants with severe plagiocephaly, 37 (66%) with a median CA of 15.6 mm exhibited no improvement after two months. In the scan age- and evaluation interval-matched case-control study, the CA value in the CHT group improved by three times that in the natural-course group (−4.6 mm [n = 33] vs. −1.55 mm [n = 24], p < 0.001). Severe plagiocephaly did not improve naturally in 66% of the cases. Therefore, CHT should be considered if the CA is >12 mm on the initial evaluation.

Cranial Shape in Infants Aged One Month Can Predict the Severity of Deformational Plagiocephaly at the Age of Six Months

“…Brief data acquisition methods have been described in our previous paper [ 6 ]. A complete 360° scan of the head including both ears was performed using a specialized 3D scanner (Artec Eva; Artec Inc., Luxembourg) whilst the head of the infant was held by the mother.…”

“…The 3D resolution was 0.2 mm and the accuracy was 0.1 mm. The 3D data were reconstructed by combining the overlapping regions in each of the successive scanned frames and converting them into standard triangular language files [ 6 ].…”

“…Data were analyzed using Artec Studio image analysis software (Artec Inc., Luxembourg) and original analysis software from the Japan Medical Company (Japan Medical Company, Tokyo, Japan) to obtain 3D images and determine the cranial shape. Figure 1 shows the methods used to determine these parameters [ 6 ]. The plane connecting the sellion (SE; the lowest point of the nasal root) and the points of the left tragion (TR) and right TR (the upper margin of the tragus) was used as the reference plane (level 0).…”

“…Cranial helmet therapy (CHT) for DP was introduced in the 2000s and has yielded good outcomes in Japan [ 4 , 5 , 6 ]. It is recommended that CHT for DP is initiated at 3–6 months of age [ 4 , 5 , 6 , 7 , 8 , 9 ].…”

“…Cranial helmet therapy (CHT) for DP was introduced in the 2000s and has yielded good outcomes in Japan [ 4 , 5 , 6 ]. It is recommended that CHT for DP is initiated at 3–6 months of age [ 4 , 5 , 6 , 7 , 8 , 9 ]. A delay in starting CHT is often encountered because DP can be improved in several cases by repositioning the infant.…”