Eye-tracking provides an objective measure of how observers direct visual attention to presented stimuli and has become an increasingly valuable tool in facial plastic surgery. It offers unique insight into how facial conditions and surgical interventions impact facial attention. A well-designed eye-tracking study can address patient questions about how others look at their face, identify targets for visual improvement, and objectively assess facial plastic surgery outcomes. Significant variability exists in eye-tracking study design and execution within facial plastic surgery, often producing data that are erroneous, difficult to interpret, or not generalizable to clinical practice. There are currently no guidelines for the design of eye-tracking studies in facial plastic surgery. Furthermore, the technical requirements for facial eye-tracking studies differ from those for non-facial studies. This article aims to synthesize the existing literature and authors’ experience to establish basic guidelines for designing eye-tracking studies in facial plastic surgery. We hope this guide will help investigators design high-quality eye-tracking studies to drive meaningful advances in the field of facial plastic surgery.
Two-Sample Mendelian Randomization Analysis of Associations Between Periodontal Disease and Risk of Cancer
Abstract Background Observational studies indicate that periodontal disease may increase the risk of colorectal, lung, and pancreatic cancers. Using a 2-sample Mendelian randomization (MR) analysis, we assessed whether a genetic predisposition index for periodontal disease was associated with colorectal, lung, or pancreatic cancer risks. Methods Our primary instrument included single nucleotide polymorphisms with strong genome-wide association study evidence for associations with chronic, aggressive, and/or severe periodontal disease (rs729876, rs1537415, rs2738058, rs12461706, rs16870060, rs2521634, rs3826782, and rs7762544). We used summary-level genetic data for colorectal cancer (n = 58 131 cases; Genetics and Epidemiology of Colorectal Cancer Consortium, Colon Cancer Family Registry, and Colorectal Transdisciplinary Study), lung cancer (n = 18 082 cases; International Lung Cancer Consortium), and pancreatic cancer (n = 9254 cases; Pancreatic Cancer Consortia). Four MR approaches were employed for this analysis: random-effects inverse-variance weighted (primary analyses), Mendelian Randomization-Pleiotropy RESidual Sum and Outlier, simple median, and weighted median. We conducted secondary analyses to determine if associations varied by cancer subtype (colorectal cancer location, lung cancer histology), sex (colorectal and pancreatic cancers), or smoking history (lung and pancreatic cancer). All statistical tests were 2-sided. Results The genetic predisposition index for chronic or aggressive periodontitis was statistically significantly associated with a 3% increased risk of colorectal cancer (per unit increase in genetic index of periodontal disease; P = .03), 3% increased risk of colon cancer (P = .02), 4% increased risk of proximal colon cancer (P = .01), and 3% increased risk of colorectal cancer among females (P = .04); however, it was not statistically significantly associated with the risk of lung cancer or pancreatic cancer, overall or within most subgroups. Conclusions Genetic predisposition to periodontitis may be associated with colorectal cancer risk. Further research should determine whether increased periodontitis prevention and increased cancer surveillance of patients with periodontitis is warranted.