[Anthropometric study on normal human auricle in Japan]

External ear anatomy and variations in neonates

It is aesthetically important that the auricle has a natural and beautiful shape. The sizes, position and symmetry of normal auricle are used for different purposes in different disciplines. A deformation in the auricle of neonates and its size or location on the face may indicate a possible anomaly. The aim of this study is to investigate the normal sizes, anomaly types, anomaly rates and the relationship between hearing screening test results and auricular anomaly of the neonatal auricle. The length, width, angle, and distance measurements of the auricle were made in neonates (n = 550). Anomaly types of auricle were observed. Goniometer was used to measure angles; digital caliper and ruler were used to measure lengths. Anomalies were detected by the method of observation. In the morphometric data of the neonatal auricle, differences were determined in length and width values in terms of gender. Various types of anomalies were observed in the right ear of 96 participants and in the left ear of 103 participants. Normal auricle size, position and symmetry are important for surgical reconstructions, hearing aid design, producing data banks on gender, age and ethnicity, and providing reference information for multiple diagnostic and forensic procedures. Recognition and early detection of auricular anomalies play an essential role in clinical diagnosis and their correction with special devices.

Age- and Sex-Related Development of the Normal Human Ear in a Child Population

BACKGROUND

A large number of researches related to auricle development have been conducted in different countries, but there were few similar studies in China, especially in Chinese children. This study was designed to investigate the auricular development by measuring normal age- and sex-related dimensions of auricles in Chinese children.

METHODS

A total of 900 participants were evaluated according to their age and gender. From the landmarks, the dimensions of the and tragus including length and width, the relevant indices, inclination angles were measured. The average score of each item was calculated according to age and gender.

RESULTS

The dimensions of the and tragus including width and length showed certain developmental patterns respectively. No significantly difference was found for the inclination angles and relative indices between different age groups and different sides.

CONCLUSIONS

The data indicated that there was a certain pattern of auricular development. There were also gender difference in the development of auricle. There were certain proportional relationships between different subunits of the auricle. These results may be useful for designing the plan of auricular reconstruction.

A Survey of Aesthetic Standards of the Ear

BACKGROUND

The aesthetic standards of the ear are very important for evaluation of auricular surgery. Few studies have previously assessed ear aesthetics, especially in China. This study aimed to investigate aesthetic standards of the ear in a Chinese population.

MATERIALS AND METHODS

A questionnaire was administered to Chinese individuals, which included assessment of the general impressions of the ear and other facial aesthetic units, the individual aesthetic subunits of the ear, the effects of different ear subunits on ear symmetry and the degree of the subunits to which the participants wanted to change. Answers were recorded on a five-point Likert-style scale. Statistical analysis was performed using SPSS ver. 17.0.

RESULTS

A total of 319 responses were received, 50.3% women and 49.7% men. The external ear received the lowest degree of attention either on the front or on the lateral view of the face in both genders. Among the individual aesthetic units, the earlobe received the most attention and the fine structures the lowest. The helix had the greatest effect on the ear symmetry. The structure that participants most wanted to change was the earlobe in males and the helix in females. There were significant differences on the evaluation of the helix and crus of helix among the groups divided according to educational background (P < 0.001).

CONCLUSION

The results showed that the structures that people were most concerned about were the helix and earlobe. There were gender differences in the results which were also influenced by education background.

Elements of morphology: standard terminology for the ear

An international group of clinicians working in the field of dysmorphology has initiated the standardization of terms used to describe human morphology. The goals are to standardize these terms and reach consensus regarding their definitions. In this way, we will increase the utility of descriptions of the human phenotype and facilitate reliable comparisons of findings among patients. Discussions with other workers in dysmorphology and related fields, such as developmental biology and molecular genetics, will become more precise. Here we introduce the anatomy of the ear and define and illustrate the terms that describe the major characteristics of the ear.

Auricular Anthropometry of Newborns at the Singapore General Hospital

Introduction: External ear abnormalities accompany many syndromes and genetic conditions. Yet, there are currently limited Asian references and no local norms for ear measurements and definitions for “low-set ears”. The authors therefore describe ear measurements in a Singapore newborn population and seek to establish the applicability of the general accepted definition of “low-set ears” being that of “less than a third of the entire ear height being above the inter-medial canthal line”. Materials and Methods: Babies managed by the Department of Neonatal and Developmental Medicine during a 3-week period were measured by 2 investigators using the Feingold and Bossert technique. Intra- and inter-rater reliabilities were calculated. The influence of various anthropometric factors on and their relationships with ear length (EL) and width (EW) was analysed. Results: A total of 104 neonates (20% preterm at birth) were included in this study. Median gestation was 38 weeks (range, 32 to 42). Mean birth weight was 2910 ± 657 g. Mean EW and EL for term infants were 2.1 ± 0.1 cm and 3.6 ± 0.3 cm respectively, without significant differences for different-sided ears, investigators, race or gender. Mean percentage of right and left ear above the denoted line was 52 ± 9% and 47 ± 10% respectively (P = 0.000), with 3rd percentile being 33%. Conclusions: Singaporean neonatal ears are comparable with other Asian neonates – larger than Hong Kong Chinese babies, though similar to Japanese newborns – but smaller than Caucasian neonates. The definition of “low-set ears” is consistent with the general accepted definition. Key words: Babies, Ear length and width, Ear measurements, Low-set ears

The external ear: More attention to detail may aid syndrome diagnosis and contribute answers to embryological questions

The human pinna has a complex shape and yet the basic components of normal structure are remarkably constant between individuals. It is precocious in its appearance during embryogenesis and it has been subject to many developmental and surgical studies, yet questions remain as to its primary embryogenesis and the causes of its malformations. Unfortunately, the vast majority of clinical reports of syndromes and of individuals with dysmorphic signs provide limited and inadequate description of the external ear. Given the intricate pattern of the pinna, and hence its potential for morphological variation, we think that more attention to the specific description of ear anomalies may lead to a better appreciation of the etiology and embryology of the malformations. Furthermore, in some cases correlation with specific syndromes may provide an aid to diagnosis. Towards those ends this paper reviews some of the controversy concerning the embryology of the pinna, and discusses a number of the better-defined anomalies of the external ear. Although it has been suggested that anomalies of the insertion and orientation of intrinsic muscles of the pinna may be responsible for variations in external ear morphology, we think it likely that in many cases the anomalous insertions may be secondary.