Telecanthus

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Diagram showing the definition of telecanthus, or dystopia canthorum Dystopia canthorum diagram.png
Diagram showing the definition of telecanthus, or dystopia canthorum

Telecanthus, or dystopia canthorum, refers to increased distance between the inner corners of the eyelids (medial canthi), while the inter-pupillary distance is normal. This is in contrast to hypertelorism, in which the distance between the whole eyes is increased. [1] Telecanthus and hypertelorism are each associated with multiple congenital disorders.

Contents

The distance between the inner corners of the eyelids is called the intercanthal distance. In most people, the intercanthal distance is equal to the width of each eye (the distance between the inner and outer corners of each eye). The average interpupillary distance is 60–62 millimeters (mm), which corresponds to an intercanthal distance of approximately 30–31 mm. [2]

Traumatic telecanthus refers to telecanthus resulting from traumatic injury to the nasal-orbital-ethmoid (NOE) complex. [1] The diagnosis of traumatic telecanthus requires a measurement in excess of those normative values. The pathology can be either unilateral or bilateral, with the former more difficult to measure. [2]

Systemic associations

Telecanthus is often associated with many congenital disorders. Congenital disorders such as Down syndrome, fetal alcohol syndrome, cri du chat syndrome, Klinefelter syndrome, Turner syndrome, Ehlers–Danlos syndrome, Waardenburg syndrome [3] often present with prominent epicanthal folds, and if these folds are nasal (as they most commonly are) they will cause telecanthus.[ citation needed ]

Etymology

Telecanthus comes from the Greek word τῆλε (tele, "far") and the latinized form of the Greek word κάνθος , (kánthos, meaning 'corner of the eyelid'. Dystopia canthorum comes from the Greek δυσ- (dus-, “bad”) and τόπος (tópos, “place”) and the latinized Greek word κάνθος, adapted to latin morphology canthorum ("of the canthi").[ citation needed ]

See also

Related Research Articles

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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.

<span class="mw-page-title-main">Waardenburg syndrome</span> Genetic condition involving hearing loss and depigmentation

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<span class="mw-page-title-main">Eyelid</span> Thin fold of skin that covers and protects the eye

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<span class="mw-page-title-main">Nasolacrimal duct</span> Carries tears from the lacrimal sac of the eye into the nasal cavity.

The nasolacrimal duct carries tears from the lacrimal sac of the eye into the nasal cavity. The duct begins in the eye socket between the maxillary and lacrimal bones, from where it passes downwards and backwards. The opening of the nasolacrimal duct into the inferior nasal meatus of the nasal cavity is partially covered by a mucosal fold.

<span class="mw-page-title-main">Canthus</span> Corner of the eye where the upper and lower eyelids meet

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<span class="mw-page-title-main">Blepharophimosis</span> Congenital anomaly in which the eye openings are small

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<span class="mw-page-title-main">Nasal bridge</span> Bony part of the nose, overlying the nasal bones

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<span class="mw-page-title-main">Frontonasal dysplasia</span> Medical condition

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<span class="mw-page-title-main">Waardenburg syndrome type 2D</span> Medical condition

Waardenburg syndrome type 2D, a subtype of the Waardenburg syndrome, is a rare congenital disorder caused by a mutation in the SLUG (SNAI2) gene. It is characterized by the lack of pigmentation in the skin, hair, and eyes as well as the abnormalities in the outer wall of the cochlea. This subtype lacks the wide distance between the eyes, known as dystopia canthorum, that is observed in most patients with Waardenburg syndrome. Those affected, exhibit varying degrees of deafness or complete hearing loss along with heterochromia and reports of early graying. This disease is observed in the neonatal stages of early life.

<span class="mw-page-title-main">Waardenburg syndrome type 1</span> Congenital disorder

Waardenburg syndrome type 1 is a congenital disorder that caused by a mutation in the PAX3 gene that results in abnormal development in the neural crest during early development. Type 1 results in early graying and white forelock and a notable distance between the eyes, noted as dystopia canthorum. Common symptoms of the disease also includes non-progressive hearing loss in majority of patients with type 1. Patients can display complete or partial heterochromia and hypoplastic blue irides and congenital leukemia.

Waardenburg syndrome type 4A is an extremely rare congenital disorder caused by a mutation in an endothelin receptor gene. It results in common Waardenburg syndrome symptoms such as abnormal hair and skin pigmentation and heterochromia, but also present with symptoms of Hirschsprung's disease. Symptoms include abdominal pain and bowel obstruction. Waardenburg syndrome type 4A is the rarest among the types, appearing only once in about every 1,000,000 individuals. There have only been a total of 50 cases reported in total as of 2016.

References

  1. 1 2 "Telecanthus - EyeWiki". eyewiki.aao.org. Retrieved 2019-12-07.
  2. 1 2 "Resident Manual of Trauma to the Face, Head, and Neck, Ed. 1" (PDF). Retrieved 12 January 2015.
  3. Tagra S, Talwar AK, Walia RL, Sidhu P (2006). "Waardenburg syndrome". Indian J Dermatol Venereol Leprol. 72 (4): 326. doi: 10.4103/0378-6323.26718 . PMID   16880590.