An epicanthic fold or epicanthus is a skin fold of the upper eyelid that covers the inner corner of the eye. However, variation occurs in the nature of this feature and the possession 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.
An eyelid is a thin fold of skin that covers and protects an eye. The levator palpebrae superioris muscle retracts the eyelid, exposing the cornea to the outside, giving vision. This can be either voluntarily or involuntarily. "Palpebral" means relating to the eyelids. Its key function is to regularly spread the tears and other secretions on the eye surface to keep it moist, since the cornea must be continuously moist. They keep the eyes from drying out when asleep. Moreover, the blink reflex protects the eye from foreign bodies. A set of specialized hairs known as lashes grow from the upper and lower eyelid margins to further protect the eye from dust and debris.
The canthus is either corner of the eye where the upper and lower eyelids meet. More specifically, the inner and outer canthi are, respectively, the medial and lateral ends/angles of the palpebral fissure.
Saethre–Chotzen syndrome (SCS), also known as acrocephalosyndactyly type III, is a rare congenital disorder associated with craniosynostosis. This affects the shape of the head and face, resulting in a cone-shaped head and an asymmetrical face. Individuals with SCS also have droopy eyelids (ptosis), widely spaced eyes (hypertelorism), and minor abnormalities of the hands and feet (syndactyly). Individuals with more severe cases of SCS may have mild to moderate intellectual or learning disabilities. Depending on the level of severity, some individuals with SCS may require some form of medical or surgical intervention. Most individuals with SCS live fairly normal lives, regardless of whether medical treatment is needed or not.
Primary ovarian insufficiency (POI), also called premature ovarian insufficiency, premature menopause, and premature ovarian failure, is the partial or total loss of reproductive and hormonal function of the ovaries before age 40 because of follicular dysfunction or early loss of eggs. POI can be seen as part of a continuum of changes leading to menopause that differ from age-appropriate menopause in the age of onset, degree of symptoms, and sporadic return to normal ovarian function. POI affects approximately 1 in 10,000 women under age 20, 1 in 1,000 women under age 30, and 1 in 100 of those under age 40. A medical triad for the diagnosis is amenorrhea, hypergonadotropism, and hypoestrogenism.
XX gonadal dysgenesis is a type of female hypogonadism in which the ovaries do not function to induce puberty in an otherwise normal girl whose karyotype is found to be 46,XX. With nonfunctional streak ovaries, she is low in estrogen levels (hypoestrogenic) and has high levels of FSH and LH. Estrogen and progesterone therapy is usually then commenced. Some cases are considered a severe version of premature ovarian failure where the ovaries fail before puberty.
Ptosis, also known as blepharoptosis, is a drooping or falling of the upper eyelid. This condition is sometimes called "lazy eye," but that term normally refers to the condition amblyopia. If severe enough and left untreated, the drooping eyelid can cause other conditions, such as amblyopia or astigmatism, so it is especially important to treat the disorder in children before it can interfere with vision development.
Young–Simpson syndrome (YSS) is a rare congenital disorder with symptoms including hypothyroidism, heart defects, facial dysmorphism, cryptorchidism in males, hypotonia, intellectual disability, and postnatal growth retardation.
Forkhead box protein L2 is a protein that in humans is encoded by the FOXL2 gene.
Transcription factor SOX-14 is a protein that in humans is encoded by the SOX14 gene.
Telecanthus, or dystopia canthorum, refers to increased distance between the inner corners of the eyelids, while the inter-pupillary distance is normal. This is in contrast to hypertelorism, in which the distance between the whole eyes is increased. Telecanthus and hypertelorism are each associated with multiple congenital disorders.
Michels syndrome is a syndrome characterised by intellectual disability, craniosynostosis, blepharophimosis, ptosis, epicanthus inversus, highly arched eyebrows, and hypertelorism. People with Michels syndrome vary in other symptoms such as asymmetry of the skull, eyelid, and anterior chamber anomalies, cleft lip and palate, umbilical anomalies, and growth and cognitive development.
Seaver Cassidy syndrome is a very rare disorder characterized by certain facial, genital, and skeletal deformities, as well as an unusual susceptibility to bleeding. Seaver Cassidy syndrome was first described in 1991 by Laurie Seaver and Suzanne Cassidy.
Blepharophimosis, ptosis, epicanthus inversus syndrome (BPES) is a rare disease characterized by the conditions it is named after: blepharophimosis, ptosis and epicanthus inversus. There are two types; type 1 is distinguished from type 2 by including the symptom of premature ovarian insufficiency (POI) in females, which causes menopausal symptoms and infertility in patients as young as 15 years old.
Ankyloblepharon is a medical condition, defined as the adhesion of the edges of the upper eyelid with the lower eyelid. Ankyloblepharon must be differentiated from blepharophimosis, in which palpebral aperture is reduced and there is telecanthus, but the eyelid margins are normal. Another condition similar to ankyloblepharon is symblepharon, in which the palpebral conjunctiva is attached to the bulbar conjunctiva. Recognition of ankyloblepharon necessitates systemic examination to detect associated abnormalities such as genitourinary and cardiac abnormalities and syndactyly.
Blepharophimosis-ptosis-esotropia-syndactyly-short stature syndrome is a very rare genetic and congenital disorder which is characterized by blepharophimosis, ptosis, V-esotropia, foot syndactyly, extra-ocular and frontal muscles weakness, low height/short stature, prognathism, and synophrys.
Acrocraniofacial dysostosis, also known as Kaplan Plauchu Fitch syndrome is a very rare hereditary disorder which is characterized by cranio-facial dysmorphisms, hearing loss, digital clubbing, and osseous anomalies. Only 2 cases have been described in medical literature.
Pai syndrome, also known as Median cleft of the upper lip-corpus callosum lipoma-midline facial cutaneous polyps syndrome, is a very rare genetic disorder which is characterized by nervous system, cutaneous, ocular, nasal and bucal anomalies with facial dysmorphisms.
Holoprosencephaly-ectrodactyly-cleft lip/palate syndrome, also simply known as Hartsfield syndrome, is a rare genetic disorder characterized by the presence of variable holoprosencephaly, ectrodactyly, cleft lip and palate, alongside generalized ectodermal abnormalities. Additional findings include endocrine anomalies and developmental delays.
