Seeing Cleft Lip from a New Angle: Crowdsourcing to Determine whether Scar Severity or Lip Angle Matters More to the General Public

Abstract

Background: Modern cleft lip surgery aims to restore symmetry and create a level, normal-appearing Cupid’s bow. However, families’ concerns often center on the degree of scarring. The authors hypothesized that the lip angle would be less influential than scar severity in layperson ratings. Methods: The authors received institutional review board approval for modifying patients’ postoperative photographs to create systematic variations displaying different levels of scarring and lip angle. Each child’s resulting composite images were presented in pairs to internet raters using Amazon Mechanical Turk. Users selected the simulated postoperative result they felt to be most normal. The Bradley-Terry model was used to determine raters’ preferences between different levels of scarring and lip angle. Results: Four children with primary unilateral cleft lip repair had their postoperative photographs modified (mean age, 1.4 years; mean follow-up, 1.0 years). Twelve-hundred crowdsourced pairwise ratings were collected for each patient (4800 combined ratings). For all four children, raters preferred images with more severe scarring than those with a greater lip angle, suggesting uneven lip angle has a more negative effect on perceived appearance. Conclusions: Online crowdsourcing postoperative lip angle had a significantly greater influence on ratings of normal appearance than does the severity of scarring. Although patients may ask about scars more often, clinically, this study suggests perceptions of a cleft lip repair result may be more likely influenced by the angle of the cleft lip repair.