Facial Surface Anthropometric Features and Measurements With an Emphasis on Rhinoplasty

The Isosceles Nasal Tip-Laser-Assisted Midline Assessment in Rhinoplasty

The accurate determination of the nasal tip's spatial location is crucial for achieving symmetry in rhinoplasty. Even minor deviations can result in asymmetrical lengths and configurations of the nostrils. Our approach centers on defining the nasal tip position by establishing the midline of the nasal base and projecting an isosceles triangle. This triangle, with the tip as the vertex and alar creases as angles, ensures symmetric sidewalls. The symmetry axis, derived from the isosceles triangle, guides the placement of the tip sidewalls and columella. To implement this, we use anatomical benchmarks such as the implantation of the nasal base and position of the alar creases, considering inherent facial asymmetries. We introduce a laser gadget as an auxiliary tool, projecting perpendicular lines to guide precise midline alignment. Marking specific points, including interbrow midpoint and alar creases, ensures accuracy. In the past 12 months, we applied this methodology in 247 rhinoplasty cases, observing improved outcomes and patient satisfaction. Our proposal of utilizing isosceles triangles provides a streamlined approach to achieving symmetry. The laser device, while beneficial, should be viewed as supportive rather than an absolute guiding measure.

Preference for Averaging in East Asian Faces: A Source of Potential Guidance in Aesthetic Plastic Surgery

Background

Relatively little research has been done on the application of objective tools in guiding Ethnic Plastic Surgery in Asian patients. The evolutionary psychology theory of koinophilia, or love of average features, presents the basis for a solution to build a foundation for crowd-sourced East Asian aesthetic standards.

Objectives

The authors hypothesize that the averaged composite face in a cohort will be viewed as significantly more attractive than their respective cohort.

Methods

Cohorts were created based on the gender of the individual in the photograph (40 females and 40 males of East Asian descent). Two surveys were created, 1 for the female cohort and the other for the male. The surveys assessed the aesthetic preference of each photograph using a Likert scale ranging from 1 to 7. Surveys were distributed using the popular crowdsourcing program Amazon Mechanical Turk (Amazon, Seattle, WA).

Results

The authors received 875 respondents for the male cohort survey and 876 respondents for the female cohort survey. For both the female and male cohorts, the composite images had a statistically significantly higher rating (P < .001) than the mean of the other images. Among other significant demographic findings, when considering both ethnicity and location of residence, Asian raters living in Asia preferred the composite significantly more than Asian raters living in North America (P < .001).

Conclusions

Raters' preference for the composite average face is in concordance with the evolutionary psychology literature. Thus, this study affirms the utility of using facial composites to guide surgeons in identifying aesthetic standards for patients of East Asian descent.

Acquisition of Precision and Reliability of Modalities for Facial Reconstruction and Aesthetic Surgery: A Systematic Review

The foundation of reconstructive and cosmetic surgery is a confluence of advanced technologies, plethora of procedures, inventive modifications, and planned strategies. In surgical planning, the most crucial steps for treating a patient are evaluating the facial morphometry and recognizing the deviations from the baseline values of facial parameters. Various imaging and non-imaging modalities and sub-modalities contribute to diagnosis, treatment planning, and follow-up care. These techniques are an important milestone of pre-, peri-, and postoperative care in facial reconstruction. The current research aims to comprehensively explain imaging and non-imaging technologies encompassing both innovative and traditional approaches in facial reconstruction. PubMed, Scopus, and Web of Science were searched from 1990 to 2022, and systematic review was conducted in accordance with the PRISMA recommendations. Undoubtedly, various factors impact the selection of facial analysis acquisition approaches and their prospective. The surgical team must understand such modalities' potential for diagnosis and treatment. The evolution of three-dimensional imaging has been fueled because of the need for devices with high speed, small size, and several functions. Automation with more efficiency and precision is the way of the future for three-dimensional imaging. Stereophotogrammetry can clearly quantify the field of facial analysis. All the publications under consideration came to the same conclusion: Canfield's Vectra three-dimensional imaging devices can provide accurate, repeatable stereophotogrammetric pictures. Although a few minor mistakes were recorded, most examined devices are deemed reliable and accurate tools for Plastic surgeons.

Three-dimensional (3D) area and volume measurements for rhinoplasty

BACKGROUND

Morphometric changes achieved in rhinoplasty are mostly analyzed on two-dimensional (2D) images. However, most of these alterations are amenable to three-dimensional (3D) analysis.

OBJECTIVES

Objective measurements for rhinoplasty are currently done on 2D photographic analyses. We believe that newer techniques will develop. This is a study to help define new parameters.

METHODS

Landmarks that are widely used in the literature were used to define the boundaries of these measurements. They comprised certain parts of the nose (tip, dorsum, radix, etc.). Measurements were done on a generic face (GF) 3D model. The model's nose was then morphed using the free, open-source 3D modeling software (Blender) to generate seven different deformed noses and to perform the area and volume measurements.

RESULTS

Each nose with a different type of deformity demonstrated significant area and volume differences. For example, comparing area measurements to GF-Pleasant nose, GF-Snub nose showed a significant difference at the tip (43.3% reduction). Volume measurements were found to be mostly parallel to the area measurements; however, some incongruences were noted.

CONCLUSIONS

We show that new area and volume measurements can be reliably developed for 3D-scanned images. These measurements can be utilized and will enrich the facial analysis and evaluation of the outcomes of rhinoplasty.

A Crowdsourced Evaluation of Facial Averageness and Attractiveness

BACKGROUND

Evolutionary psychologists have demonstrated that humans are attracted to individuals who possess average anatomy for the population.

OBJECTIVES

The aim of this study was to prove that a composite of average facial features would be more attractive to raters than the cohort utilized to create the composite.

METHODS

The male and female cohorts each consisted of 41 standardized frontal-view monochrome photographs, with 1 composite image derived from the other 40 real images. Amazon Mechanical Turk, a widely used crowdsourcing platform, was utilized to obtain ratings of images ranging from 1 to 7, with 1 and 7 being least and most attractive, respectively. The strength of the preference for the composite over the real images was assessed by the difference between the mean rating of the composite and real images.

RESULTS

In total, 870 and 876 respondents were recruited to rate the male and female cohorts, respectively. For the male and female cohorts, the composite image was rated significantly higher than the rest of the cohort overall and across all ages, genders, and countries of residence (all P < 0.0001). For both cohorts, the strength of the preference was significantly higher for European respondents and lower for South American and nonbinary respondents (all P < 0.05).

CONCLUSIONS

This study reveals that average facial anatomy is perceived as most attractive across all demographics, a finding that is hoped to serve as a stepping stone for further studies leading to objective cosmetic quantifications and integrating evidence-based medicine into aesthetic surgery.

Evaluating the agreement and reliability of a web-based facial analysis tool for rhinoplasty

PURPOSE

Rhinoplasty is one of the most common and challenging plastic surgery procedures. Facial analysis is a crucial step in planning. Utilizing three-dimensional (3D) model of a patient's face is an emerging way of performing facial analysis. This paper evaluates the agreement and reliability of facial measurements taken using a web app, located at digitized-rhinoplasty.com, that utilizes 3D models of the patient's face.

METHODS

Eleven measurements were calculated on 16 human subjects. Three methods of measurements were performed: direct measurements on human subjects' faces, measurements on 2D photographs, and measurements on 3D models of face scans. The Bland-Altman plot is used for testing the agreement between the web app and the well-known Blender 3D modeling software. Intra-rater and inter-rater reliability was calculated and compared for 2D and 3D methods using the intraclass correlation coefficient (ICC) method. The statistical analysis methods were checked for the normality and homoscedasticity assumptions.

RESULTS

The results indicate that the web app and Blender software show agreement within 95% confidence limits. The web app performs well in intra-rater and inter-rater reliability statistical analysis. The web app's reliability scores are consistently better than facial analysis software which was found highly reliable in a previous study. We also compare the methods of measurements in terms of time, ease of use, and cost.

CONCLUSION

The utilization of 3D computer modeling for facial analysis has its advantages and started to become more common due to recent advances in technology. The web app utilizes 3D face scans for pre-operative planning and post-operative evaluation of facial surgeries. The web app performs well in agreement and inter-/intra-reliability analysis and performs consistently better than software that works utilizing 2D photographs. The web app provides accurate, repeatable, affordable, and fast facial measurements for facial analysis when compared to direct and 2D methods.

Digitizing rhinoplasty: a web application with three-dimensional preoperative evaluation to assist rhinoplasty surgeons with surgical planning

PURPOSE

Rhinoplasty is one of the most common and challenging plastic surgery procedures. The results of the operation have a significant impact on the facial appearance. The planning is critical for successful rhinoplasty surgery. In this paper, we present a web application designed for preoperative rhinoplasty surgery planning.

METHODS

The application uses the three-dimensional (3D) model of a patient's face and facilitates marking of an extensive number of facial features and auto-calculation of facial measurements to develop a numerical plan of the surgery. The web application includes definitions, illustrations, and formulas to describe the features and measurements. In addition to the existing measurements, the user can calculate the distance between any two points, the angle between any three points, and the ratio of any two distances. We conducted a survey among experienced rhinoplasty surgeons to get feedback about the web application and to understand their attitude toward utilizing 3D models for preoperative planning.

RESULTS

The web application can be accessed and used through any web browser at digitized-rhinoplasty.com. The web application was utilized in our tests and also by the survey participants. The users successfully marked the facial features on the 3D models and reviewed the auto-calculated measurements. The survey results show that the experienced surgeons who tried the web application found it useful for preoperative planning and they also think that utilizing 3D models is beneficial.

CONCLUSIONS

The web application introduced in this paper helps analyzing the patient's face in details utilizing 3D models and provides numeric outputs to be used in the rhinoplasty operation planning. The experienced rhinoplasty surgeons that participated to our survey agree that the web app would be a beneficial tool for rhinoplasty surgeons. We aim to further improve the web application with more functionality to help surgeons for preoperative planning of rhinoplasty.