A Photo Score For Aesthetic Outcome In Sagittal Synostosis: An ERN CRANIO Collaboration

Abstract

European Reference Network (ERN) CRANIO is focused on optimizing care for patients with rare or complex craniofacial anomalies, including craniosynostosis and/or rare ear, nose, and throat disorders. The main goal of ERN CRANIO is to collect uniform data on treatment outcomes for multicenter comparison. We aimed to develop a reproducible and reliable suture-specific photo score that can be used for cross-center comparison of phenotypical severity of sagittal synostosis and aesthetic outcome of treatment. We conducted a retrospective study among nonsyndromic sagittal synostosis patients aged <19 years. We included preoperative and postoperative photo sets from 6 ERN CRANIO centers. Photo sets included bird's eye, lateral, and anterior-posterior views. The sagittal synostosis photo score was discussed in the working group, and consensus was obtained on its contents. Interrater agreement was assessed with weighted Fleiss' Kappa and intraclass correlation coefficients.The photo score consisted of frontal bossing, elongated skull, biparietal narrowness, temporal hollowing, vertex line depression, occipital bullet, and overall phenotype. Each item was scored as normal, mild, moderate, or severe. Results from 36 scaphocephaly patients scored by 20 raters showed kappa values ranging from 0.38 [95% bootstrap CI: 0.31, 0.45] for biparietal narrowness to 0.56 [95% bootstrap CI: 0.47, 0.64] for frontal bossing. Agreement was highest for the sum score of individual items [intraclass correlation coefficients agreement 0.69 [95% CI: 0.57, 0.82]. This is the first large-scale multicenter study in which experts investigated a photo score to assess the severity of sagittal synostosis phenotypical characteristics. Agreement on phenotypical characteristics was suboptimal (fair-moderate agreement) and highest for the summed score of individual photo score items (substantial agreement), indicating that although experts interpret phenotypical characteristics differently, there is consensus on overall phenotypical severity.

FIGURE 1

Schematic figure depicting scaphocephaly features in red dotted lines.

FIGURE 2

Total scores of all raters and subjects for each category.

FIGURE 3

Pairwise kappa analyses. Each square represents 1 pair of raters, with the color of the square indicating the amount of agreement as shown in the legend and the number in the square indicating the κ value. Abbreviations: R indicates rater.

FIGURE 4

Relation of individual items with overall phenotype. Scatterplots show the scores from all raters for all subjects.