Photo anthropometric variations in Japanese facial features: Establishment of large-sample standard reference data for personal identification using a three-dimensional capture system

Assessment of the reproducibility and accuracy of the Visia® Complexion Analysis Camera System for objective skin analysis of facial wrinkles and skin age

Objective

This study aimed to investigate the reproducibility and accuracy of the Visia® Complexion Analysis Camera System by Canfield Scientific for objective skin analysis.

Methods

Nineteen participants underwent facial capture with the Visia® camera following a standardised protocol. During the first session, the participants sat down and positioned their faces in a capture rig, closed their eyes and had their faces captured from the left, front and right sides, with threefold repetition of the captures from the front side. After 4 weeks, the participants underwent recapture in a similar manner. Based on the frontal views, data for two measurement methods of the Visia® camera system, the absolute scores and the percentiles, were obtained with regard to the skin criterion wrinkles via automated software calculation. Means and standard deviations were evaluated. Based on the side views, the data for the Truskin Ages® were calculated by the Visia® camera system and compared with the calendrical ages, which served as the gold standard for comparison.

Results

In the assessment of the reproducibility of the data of the capture system the standard deviation from the frontal captures among all participants was about 3% when the absolute scores of the wrinkles were compared with each other; specifically, the average deviation was 3.36% during the first capture session and 3.4% during the second capture session. Meanwhile, the standard deviation of the measurements was about 9% when the percentiles were compared; specifically, the average deviation was 8.2% during the first capture session and 10.7% during the second capture session. In the assessment of the accuracy the correlation between the calendrical age and the calculated Truskin Age® for both facial sides was very high at a correlation coefficient rho value of >0.8 (right side: r=0.896; left side: r=0.827) and statistically significant at a p-value of <0.001. The average calendrical age and Truskin Age® deviated only slightly from each other and did not differ significantly (right side: p=0.174; left side: p=0.190). The Truskin Age® was slightly higher than the calendrical age by a mean value of 1.37 years for both facial sides. The analysis of the absolute differences revealed that in 50% of the cases, there was a maximum difference of 3 years, and in 75% of the cases, there were maximum differences of 4.5 years for the right side and 5.5 years for the left side.

Conclusion

The assessment of the reproducibility and accuracy of the objective measurement method, the Visia® camera system, contributed to the validation of the system. The evaluation of the reproducibility revealed a satisfactory precision of the repeated captures when investigating facial wrinkles. Absolute scores should be preferred over percentiles owing to their better precision. The calculation of the accuracy of the Truskin Age® data from the Visia® camera system revealed only a slight deviation from the true calendrical ages. The correlation between both data groups was highly significant.

Systematic Review and Meta-analysis of Facial Anthropometric Variations Among Cisgender Females of Different Ethnicities: Implications for Feminizing Facial Gender Affirming Surgery

BACKGROUND

Feminizing Facial Gender-Affirming Surgery (FFGAS) is gaining popularity among the diverse population of patients impacted by gender incongruence. However, most studies examining facial femininity are based on Caucasians. Thus, it is unclear if ethnic differences exist in anthropometric measures relevant to FFGAS procedures. This study aims to analyze ethnic anthropometric variations in the cisgender female face to identify differences that are potentially relevant to FFGAS.

METHODS

A systematic review and meta-analysis of the PubMed, EMBASE, and Cochrane databases was performed following PRISMA guidelines on June 25, 2021. Original studies reporting facial anthropometry in cisgender women were included. Anthropometric measures of interest included mandibular and zygomatic width, facial and forehead height, and nasolabial angle. A meta-analysis was performed using a linear mixed-effects model for each anthropometric measure.

RESULTS

A total of 1246 abstracts were screened, yielding 21 articles that met the inclusion criteria. Facial anthropometric data of 4792 cisgender females of 16 different ethnicities were analyzed. This meta-analysis demonstrated that compared with Caucasian cisgender women, Japanese, Chinese, and Korean cisgender women had a wider mandible (Japanese +20.13 mm [SE 4.43, P<0.001, P value adjusted for multiple comparisons (p-adj)=0.002], Chinese +16.22 mm [SE 4.39, P=0.002, p-adj=0.013]; and Korean +14.46 mm [SE 3.97, P=0.002, p-adj=0.014]). Further, when compared with Caucasian cisgender women, Chinese cisgender women demonstrated a larger zygomatic width, African American cisgender women tended to have smaller nasolabial angles, and Indian and Japanese cisgender women tended to have a smaller and larger facial height, respectively. However, following P value adjustment for multiple comparisons, these differences were not found to be statistically significant.

CONCLUSIONS

We found that mandibular width tends to be greater for Japanese and Chinese cisgender women relative to Caucasian cisgender women. This data may be useful in counseling patients during preoperative evaluations ahead of mandibular reduction. No other anthropometric features were found to be significantly different among the ethnic groups studied. This portends that current approaches to FFGAS, which emphasize patient-specific needs and maintenance of a harmonious appearance, may require minimal or no adjustment to account for ethnic facial anthropometric differences.

Determination of the Difference Between Men and Women Anthropometry Auricles Using Photogrammetric Method in Sundanese Ethnic Group

Abstract

Auricle is one of the features that determine the face appearance. Furthermore, its shape and size are influenced by age, gender, and ethnicity. Knowledge of the normal dimensional shape, ear growth patterns, and deformity is important in diagnosing various congeital disorders. The auricle dimensions data in the Deutro-Malay population are still unavailable, specifically for the Sundanese ethnic group.

Purpose

To determine the anthropometry of adult auricles in the Sundanese population.

Patients and Methods

This was a quantitative descriptive study with a cross-sectional approach. The subjects used were Sundanese aged 18-65 years old who visited the Otorhinolaryngology-Head and Neck Surgery outward at Dr. Hasan Sadikin Hospital, Bandung. Their data were obtained by photogrammetric techniques from the results of the ear photographs captured, which were then measured with ImageJ 1.48 software, and analyzed using descriptive statistics.

Results

The mean value of seven anthropometric parameters of Sundanese auricle were as follows: For men, auricle length = 6.29 cm ± 0.47, auricle width = 2.95 cm ± 0.26, auricle floor = 4.71 cm ± 0.49, lobule length = 1.90 cm ± 0.24, lobule width = 1.83 cm ± 0.22, concha length = 2.74 cm ± 0.17, and concha width = 1.43 cm ± 0.15. Meanwhile in women, auricle length = 6.09 cm ± 0.42, auricle width = 2.88 cm ± 0.25, auricle floor = 4.58 cm ± 0.47, lobule length = 1.95 cm ± 0.27, lobule width = 1.82 cm ± 0.21, concha length = 2.57 cm ± 0.21, and concha width = 0.42 cm ± 0.19.

Conclusion

In Sundanese ethnic, auricle length, width, and floor, as well as concha length of men tended to be greater than women. However, the women's lobule length was longer compared to men's, while the lobule and concha width tended to be the same.

Ocular phenotype related SNP analysis in Southern Han Chinese population from Guangdong province

Ocular phenotype is recognizable among Asians, including eyelid fold, fissure inclination, and canthal index. Here we screened 27 facial phenotype-associated SNPs and reported a preliminary study in 246 Chinese individuals of Han origin in Guangdong province. Results showed that rs17760296 could explain 6.2% of the eyelid fold variation and double eyelids were more likely to appear when one's genotype was TT. With respect to the canthal index, rs4791774 and rs642961 were significantly associated with it. However, no individual SNP was associated with fissure inclination. We further constructed two models to predict eyelid fold and canthal index and evaluated them with receiver operating characteristic (ROC) curves and support vector machine (SVM) regression, respectively. The models showed a moderate-to-high predictive capacity (AUC = 0.75, sensitivity = 76%, and specificity = 72%) for the eyelid fold while a mild performance (R² = 0.1074, MSE = 0.0005, P-value = 0.024) for the canthal index. In conclusion, our study indicates that rs17760296 could be selected into the facial phenotype prediction system for the Southern Han Chinese population. More SNPs are encouraged to improve the prediction accuracy of the canthal index besides rs4791774 and rs642961.

Facial Identity Verification Robust to Pose Variations and Low Image Resolution: Image Comparison Based on Anatomical Facial Landmarks

Face comparison/face mapping is one of the promising methods in face biometrics which needs relatively little effort compared with face identification. Various factors may be used to verify whether two faces are of the same person, among which facial landmarks are one of the most objective indicators due to the same anatomical definition for every face. This study identified major landmarks from 2D and 3D facial images of the same Korean individuals and calculated the distance between the reciprocal landmarks of two images to examine their acceptable range for identifying an individual to obtain standard values from diverse facial angles and image resolutions. Given that reference images obtained in the real-world could be from various angles and resolutions, this study created a 3D face model from multiple 2D images of different angles, and oriented the 3D model to the angle of the reference image to calculate the distance between reciprocal landmarks. In addition, we used the super-resolution method of artificial intelligence to address the inaccurate assessments that low-quality videos can yield. A portion of the process was automated for speed and convenience of face analysis. We conclude that the results of this study could provide a standard for future studies regarding face-to-face analysis to determine if different images are of the same person.

Facial Anthropometric Proportion of Chinese Han Nationality

Facial anthropometric measurements play an important part not only in forensic cases but also in clinical treatments. The utilization of 2D photograph methods in facial anthropometric studies to found database with age, gender, ethnicity, and region was expanded by other races but little for Han nationality. This study was undertaken to describe reference ranges of facial anthropometric proportions of Han nationality and compare the anthropometric characteristics with other ethnicities. Our subjects focused on full-face photos of Han nationality in South China which consisted of 1176 healthy person (425 adult males, 421 adult females and 157 underage boys and 173 underage girls). Eight anthropometric landmarks on photos were examined by ImageJ software, and 7 anthropometric ratios were analyzed. The results indicated sex- and age- and ethnics-related anthropometric variations in Chinese Han nationality in South China. For adults, females have larger ratios in intercanthal-nasal width and lip height index and smaller nose width index; for impubes, boys were larger in lip height index and smaller in lip width ratios than girls, but as age achieved, the underage boys and girls exhibited a significantly larger nose width index and lip width index, smaller canthal index, intercanthal-nasal width and lip height index. Comparing with Japanese, India, North American and Persian, Chinese Han showed great difference in facial anthropometric proportions.

Three-dimensional shape variation and sexual dimorphism of the face, nose, and mouth of Japanese individuals

Three-dimensional (3D) shape variations of the face and facial parts in Japanese adults were examined to collect basic data to be used for facial comparison in forensics. In total, 1000 3D facial scans (500 males, 500 females) of Japanese individuals were re-meshed into anatomically homologous shape models and analyzed by principal component analysis (PCA) after Procrustes superimposition. Facial parts (the nose and the mouth) were segmented from homologous face models and analyzed by PCA, too. Among all kinds of objects (the face, the nose, and the mouth), the most predominant shape variation represented by the first principal component (PC1) was the height-width proportion. The second largest variation (PC2) in the face and the nose was depth; for the mouth, it was the relative protrusion of the upper and lower lips. We interpreted predominant shape variations represented by the first five principal components (PCs) in each object. Asymmetric shape variations were observed within these PCs for the nose and the mouth. Sexual dimorphism of the face and the facial parts was also examined by testing the significance of sex-linked differences in PC scores. A significant difference was found between males and females for many PCs. Sexual dimorphism was examined also by emphasizing the shape difference between average male and female faces. Our results revealed predominant 3D shape variations and sexual dimorphism of the face and facial parts. The results may be informative for performing facial comparison in police investigations, an increasingly used technique.

Craniofacial Anthropometric Profile of East Asians

Facial anthropometric data has significant ethnic variation. East Asia, comprised of fourteen countries, represents a significant proportion of the global population. This systematic review presents the facial anthropometric data collected from these countries. The systematic review was conducted in accordance with PRISMA guidelines. An electronic search of the MEDLINE database returned 3054 articles. Twenty articles were considered eligible for inclusion. Nine studies were conducted in China, 1 in Indonesia, 2 in Japan,3 in Korea, 4 in Malaysia, and 1 was a multicentre study conducted in China, Japan, Thailand, and Vietnam. Qualitative and quantitative parameters were extracted from the20 studies. No data was found for the other East Asian countries. There is a paucity of facial anthropometric data for East Asian countries despite their high burden of craniofacial anomalies and a strong demand for cosmetic facial surgery, both of which would benefit from the collection of robust craniofacial norms. It is in the interest of both the craniofacial surgeon and the East Asian patient to collect baseline facial anthropometric data for this population.

A Preliminary Study of the Reliability of Anatomical Facial Landmarks Used in Facial Comparison

Anatomical landmarks are considered the most objective indicators for use in forensic facial comparisons. Therefore, accurately identifying and locating these landmarks is the beginning of reliable facial comparison. This study evaluated the accuracy with which facial landmarks are located and examined their reliability according to type of landmark, head posture, and image quality. Nine operators located a series of landmarks on prepared facial images used to produce comparison images. Then, the average distances between the reciprocal landmarks (ADRL) on the reference and the comparison images were measured as indicators of landmark reliability. We found that a set of landmarks had higher or lower reliability as a function of the head angle and image quality. More reliable landmarks were associated with certain head postures and degrees of image quality. These should be used for facial comparison analysis depending on various head and image conditions.

Estimation of 2D to 3D dimensions and proportionality indices for facial examination

Photo-anthropometry is a metric-based facial image comparison technique where measurements of the face are taken from an image using predetermined facial landmarks. In particular, dimensions and proportionality indices (DPIs) are compared to DPIs from another facial image. Different studies concluded that photo-anthropometric facial comparison, as it is currently practiced, is unsuitable for elimination purposes. The major limitation is the need for images acquired under very restrictive, controlled conditions. To overcome this latter issue, we propose a novel methodology to estimate 3D DPIs from 2D ones. It uses computer graphic techniques to simulate thousands of facial photographs under known camera conditions and regression to derive the mathematical relationship between 2D and 3D DPIs automatically. Additionally, we present a methodology that makes use of the estimated 3D DPIs for reducing the number of potential matches of a given unknown facial photograph within a set of known candidates. The error in the estimation of the 3D DPIs can be as large as 35%, but both I and III quartiles are consistently inside the ±5% range. The methodology for filtering cases has demonstrated to be useful in the task of narrowing down the list of possible candidates for a given photograph. It is able to remove on average (validated using cross-validation technique) 57% and 24% of the negative cases, depending on the amounts of DPIs available. Limitations of the work developed together with open research lines are included within the Discussion section.

The 3D Tele Motion Tracking for the Orthodontic Facial Analysis

Aim. This study aimed to evaluate the reliability of 3D-TMT, previously used only for dynamic testing, in a static cephalometric evaluation. Material and Method. A group of 40 patients (20 males and 20 females; mean age 14.2 ± 1.2 years; 12–18 years old) was included in the study. The measurements obtained by the 3D-TMT cephalometric analysis with a conventional frontal cephalometric analysis were compared for each subject. Nine passive markers reflectors were positioned on the face skin for the detection of the profile of the patient. Through the acquisition of these points, corresponding plans for three-dimensional posterior-anterior cephalometric analysis were found. Results. The cephalometric results carried out with 3D-TMT and with traditional posterior-anterior cephalometric analysis showed the 3D-TMT system values are slightly higher than the values measured on radiographs but statistically significant; nevertheless their correlation is very high. Conclusion. The recorded values obtained using the 3D-TMT analysis were correlated to cephalometric analysis, with small but statistically significant differences. The Dahlberg errors resulted to be always lower than the mean difference between the 2D and 3D measurements. A clinician should use, during the clinical monitoring of a patient, always the same method, to avoid comparing different millimeter magnitudes.

Quantitative assessment of the facial features of a Mexican population dataset

The present study describes the morphological variation of a large database of facial photographs. The database comprises frontal (386 female, 764 males) and lateral (312 females, 666 males) images of Mexican individuals aged 14-69 years that were obtained under controlled conditions. We used geometric morphometric methods and multivariate statistics to describe the phenotypic variation within the dataset as well as the variation regarding sex and age groups. In addition, we explored the correlation between facial traits in both views. We found a spectrum of variation that encompasses broad and narrow faces. In frontal view, the latter is associated to a longer nose, a thinner upper lip, a shorter lower face and to a longer upper face, than individuals with broader faces. In lateral view, antero-posteriorly shortened faces are associated to a longer profile and to a shortened helix, than individuals with longer faces. Sexual dimorphism is found in all age groups except for individuals above 39 years old in lateral view. Likewise, age-related changes are significant for both sexes, except for females above 29 years old in both views. Finally, we observed that the pattern of covariation between views differs in males and females mainly in the thickness of the upper lip and the angle of the facial profile and the auricle. The results of this study could contribute to the forensic practices as a complement for the construction of biological profiles, for example, to improve facial reconstruction procedures.