Community hub
Recent from talks
Knowledge base stats:
Talk channels stats:
Members stats:
Epicanthic fold
An epicanthic fold or epicanthus is a skin fold of the upper eyelid that covers the inner corner (medial canthus) of the eye. However, variation occurs in the nature of this feature and the presence of "partial epicanthic folds" or "slight epicanthic folds" is noted in the relevant literature. Various factors influence whether epicanthic folds form, including ancestry, age, and certain medical conditions.
The primary cause of the epicanthic fold is the hypertrophy of the preseptal (anterior to the orbital septum) portion of the orbicularis oculi muscle.
Epicanthus means 'above the canthus', with epi-canthus being the Latinized form of the Ancient Greek ἐπί κανθός: 'corner of the eye'.
Variation in the shape of the epicanthic fold has led to four types being recognised:
The highest frequency of occurrence of epicanthic folds is found in specific populations or ethnicities: East Asians, Southeast Asians, Central Asians, North Asians, Polynesians, Micronesians, Indigenous peoples of the Americas, Sámi people and some African people (especially among Khoisan and Nilotic people). Among South Asians, they occur at very high frequencies among the Nepalis, Bhutanese,[better source needed] Northeast Indians, Kirati people and certain Adivasi tribes of Eastern and Southern India. It is also commonly found in Northern India, especially in Kashmir. The Hazara people in Afghanistan and Pakistan commonly have this trait. Some people in Eastern/Northern Pakistan have this trait.
In some of these populations, the trait is almost universal. This is especially true in Japan and South Korea, where a majority, up to 90% in some estimations, of adults naturally have this feature. In Southern China and Southeast Asia it's about 70 % having the feature, while 30 % naturally have double eyelids.
Epicanthic folds also occur, at a considerably lower frequency, in other populations: Europeans (e.g., Scandinavians, English, Irish, Hungarians, Russians, Poles, Lithuanians, Latvians, Finns, and Estonians), Jews, South Asians (Bengalis, Sinhalese, among other groups in eastern and southern South Asia), Nilotes, Cushites, and Amazigh people.
The degree of development of the fold between individuals varies greatly, and attribution of its presence or absence is often subjective, being to a degree relative to the occurrence of the trait within the community of the specific observer. Also, its frequency varies but can be found in peoples all over the world. Its use, therefore, as a phenotypic marker to define biological populations is debatable.
Hub AI
Epicanthic fold AI simulator
(@Epicanthic fold_simulator)
Epicanthic fold
An epicanthic fold or epicanthus is a skin fold of the upper eyelid that covers the inner corner (medial canthus) of the eye. However, variation occurs in the nature of this feature and the presence of "partial epicanthic folds" or "slight epicanthic folds" is noted in the relevant literature. Various factors influence whether epicanthic folds form, including ancestry, age, and certain medical conditions.
The primary cause of the epicanthic fold is the hypertrophy of the preseptal (anterior to the orbital septum) portion of the orbicularis oculi muscle.
Epicanthus means 'above the canthus', with epi-canthus being the Latinized form of the Ancient Greek ἐπί κανθός: 'corner of the eye'.
Variation in the shape of the epicanthic fold has led to four types being recognised:
The highest frequency of occurrence of epicanthic folds is found in specific populations or ethnicities: East Asians, Southeast Asians, Central Asians, North Asians, Polynesians, Micronesians, Indigenous peoples of the Americas, Sámi people and some African people (especially among Khoisan and Nilotic people). Among South Asians, they occur at very high frequencies among the Nepalis, Bhutanese,[better source needed] Northeast Indians, Kirati people and certain Adivasi tribes of Eastern and Southern India. It is also commonly found in Northern India, especially in Kashmir. The Hazara people in Afghanistan and Pakistan commonly have this trait. Some people in Eastern/Northern Pakistan have this trait.
In some of these populations, the trait is almost universal. This is especially true in Japan and South Korea, where a majority, up to 90% in some estimations, of adults naturally have this feature. In Southern China and Southeast Asia it's about 70 % having the feature, while 30 % naturally have double eyelids.
Epicanthic folds also occur, at a considerably lower frequency, in other populations: Europeans (e.g., Scandinavians, English, Irish, Hungarians, Russians, Poles, Lithuanians, Latvians, Finns, and Estonians), Jews, South Asians (Bengalis, Sinhalese, among other groups in eastern and southern South Asia), Nilotes, Cushites, and Amazigh people.
The degree of development of the fold between individuals varies greatly, and attribution of its presence or absence is often subjective, being to a degree relative to the occurrence of the trait within the community of the specific observer. Also, its frequency varies but can be found in peoples all over the world. Its use, therefore, as a phenotypic marker to define biological populations is debatable.