The Use of Eye-tracking Technology in Cleft Lip: A Literature Review

Eye-tracking has become an increasingly popular research tool within the field of cleft lip and/or palate (CL+/−P). Despite this, there are no standardized protocols for conducting research. Our objective was to conduct a literature review of the methodology and outcomes of previous publications using eye-tracking in CL+/−P. METHODS: The PubMed, Google Scholar, and Cochrane databases were searched to identify all articles published up to August 2022. All articles were screened by two independent reviewers. Inclusion criteria included using eye-tracking, image stimuli of CL+/−P, and outcome reporting using areas of interest (AOIs). Exclusion criteria included non-English studies, conference articles, and image stimuli of conditions other than CL+/−P. RESULTS: Forty articles were identified, and 16 met the inclusion/exclusion criteria. Thirteen studies only displayed images of individuals following cleft lip surgery with three only displaying unrepaired cleft lips. Significant variation was found in study design, particularly in the AOIs used to report gaze outcomes. Ten studies asked participants to provide an outcome score alongside eye-tracking; however, only four compared outcome data to eye-tracking data. This review is primarily limited by the minimal number of publications in this area. CONCLUSIONS: Eye-tracking can be a powerful tool in evaluating appearance outcomes following CL+/−P surgery. It is currently limited by the lack of standardized research methodology and varied study design. Before future work, a replicable protocol should be developed to maximize the potential of this technology.