A Clinical Photographic Method to Evaluate the Need for Helmet Therapy in Deformational Plagiocephaly

Purpose: With an increase in positional plagiocephaly patients, various therapy methods have been researched and helmet therapy is the most widely used and effective treatment method. To devise a method that would allow medical professionals and patients' parents to more easily identify the shape and outcomes before and after the therapy. Methods: This study included 399 patients who had helmet therapy from November 2014 to February 2016. Patients wore a cast helmet for more than 20hours per day. A cranial caliper was used to measure their head before they wore the helmet (prehelmet), once a month during outpatient visits, and 6 months after they stopped wearing the helmet (posthelmet). Clinical photographs were taken on a transparent acrylic sheet with a grid of 5-mm intervals to measure cranial vault asymmetry (CVA), cranial vault asymmetry index (CVAI), and symmetry ration (SR). The patients' photographs were then measured twice: first against the background without the grid and then against the background with the grid. Results: Average age at prehelmet was 20 weeks while their average therapy period was 12 weeks. Patients' prehelmet CVA was 13.3mm, and their posthelmet CVA was 3.1mm. Their prehelmet CVAI was 10.1%, and their posthelmet CVAI was 2.1% (P<0.001). Their overall prehelmet and posthelmet SRs were 0.820 and 0.969, respectively (P<0.001). In addition, the measurements based on clinical photographs with and without the grid were compared using Fleiss kappa. The results showed κ=0.847 and 0.956 when the patient was mild, κ=0.744 and 0.919 when it was moderate, and κ=0.767 and 0.924 when it was severe (P<0.001). In all 3 patients, the consistency was higher with the grid. Conclusion: Since cast helmet manufacturing for positional plagiocephaly therapy does not require computed tomography scanning, there is no need to administer a sedative, nor does it pose any radiation exposure risk. Since the cast helmet is easier to manufacture and operate and is more cost effective, it could be used to treat more people. In addition, it would be useful for both medical professionals and patients' guardians to use clinical photographs with the acrylic sheet with the grid as a method to analyze shapes and outcomes before and after therapy, along with traditional CVA and CVAI.