Related Experiment Video
Updated: May 4, 2026
Quantitative Assessment Protocol for Facial Soft Tissue Volumetric Changes with Stereophotogrammetry
Published on: December 9, 2025
Outcome analysis after helmet therapy using 3D photogrammetry in patients with deformational plagiocephaly: the role
Mahsa Bidgoli Moghaddam1, Trevor M Brown1, April Clausen1
1The Hospital for Sick Children, Division of Plastic and Reconstructive Surgery, Department of Surgery, University of Toronto, 555 University Ave, Toronto, ON M5G 1X8, Canada.
Insights
Deformational plagiocephaly (DP) treatment with cranial molding helmets significantly improves infant head shape symmetry. Early intervention, before 7 months, yields the best results, as measured by 3D photogrammetry.
Area of Science:
- Pediatric orthopedics
- Cranial deformities
- 3D imaging analysis
Background:
- Deformational plagiocephaly (DP) is a common infant condition.
- Current treatments include repositioning and helmet therapy.
- Previous outcome measures lack comprehensive shape and volume assessment.
Purpose of the Study:
- To evaluate the efficacy of cranial molding helmet therapy for DP.
- To utilize Root Mean Square (RMS) analysis for precise head shape assessment.
- To correlate treatment outcomes with patient age.
Main Methods:
- 3D photogrammetry captured infant head shape before and after helmet treatment.
- RMS analysis quantified cranial symmetry by comparing surface distances.
- 40 infants aged 4-10 months with DP were included.
Main Results:
- Over 95% of patients showed improved cranial symmetry post-treatment.
- A statistically significant correlation was found between age at treatment initiation and symmetry improvement.
- Earlier treatment (before 7 months) resulted in greater symmetry gains.
Conclusions:
- Cranial molding helmet therapy is effective for treating DP.
- RMS analysis using 3D photogrammetry provides a robust measure of treatment efficacy.
- Initiating helmet therapy before 7 months of age maximizes positive outcomes.
Abstract:
Deformational plagiocephaly (DP) is a multifactorial non-synostotic cranial deformity with a reported incidence as high as 1 in 7 infants in North America. Treatment options have focused on non-operative interventions including head repositioning and the use of an orthotic helmet device. Previous studies have used linear and two dimensional outcome measures to assess changes in cranial symmetry after helmet therapy. Our objective was to demonstrate improvement in head shape after treatment with a cranial molding helmet by using Root Mean Square (RMS), a measure unique to 3D photogrammetry, which takes into account both changes in volume and shape over time. Three dimensional photographs were obtained before and after molding helmet treatment in 40 infants (4-10 months old) with deformational plagiocephaly. Anatomical reference planes and measurements were recorded using the 3dMD Vultus(®) analysis software. RMS was used to quantify symmetry by superimposing left and right quadrants and calculating the mean value of aggregate distances between surfaces. Over 95% of the patients demonstrated an improvement in symmetry with helmet therapy. Furthermore, when the sample of infants was divided into two treatment subgroups, a statistically significant correlation was found between the age at the beginning of treatment and the change in the RMS value. When helmet therapy was started before 7 months of age a greater improvement in symmetry was seen. This work represents application of the technique of RMS analysis to demonstrate the efficacy of treatment of deformational plagiocephaly with a cranial molding helmet.
More Related Videos
07:30A Test Bed to Examine Helmet Fit and Retention and Biomechanical Measures of Head and Neck Injury in Simulated Impact
Published on: September 21, 2017
08:03Midface Hypoplasia and Cranial Base Morphology in Syndromic Craniosynostosis: A Comparative Analysis Study Using a Predictive Regression Model
Published on: November 4, 2025