Euryblepharon is characterised by increased vertical separation of the temporal aspect of the palpebral fissure so that the palpebral conjunctiva is not in apposition with the eye. The enlargement of palpebral fissure is accompanied by variable degree of lower eyelid ectropion. The lower eyelid ectropion is caused by vertical shortening of the lower eyelid relative to the horizontal dimensions of the opposing upper eyelid. In euryblepharon, palpebral apertures are larger than normal and it may be associated with epicanthus. Widening of palpebral fissure may give the appearance of eyelid ptosis. The eyelids are normally developed but the insertions of the canthal tendons appear to be widely or anteriorly placed. Frequently, the palpebral fissure has downward slant as well because of an inferiorly displaced attachment of the lateral canthal tendon.
Euryblepharon is present at birth and there is no other associated primary ocular abnormality. In contrast, secondary enlargement of the palpebral aperture may accompany a variety of ocular abnormalities.
This condition was first described by Desmarres (1854). The average length of the lid fissures at different ages is given by Duke-Elder and Cook (1963). It increases from 18.35 mm. at birth to 29.68 mm. at 24 to 26 years of age. One half of this increase occurs in the first 4 years of life. The length is slightly less for females.
Garg Ashok, Rosen Emanuel, Mortensen Jes, Toukhy Essam El, Dhaliwal Ranjit S. Instant Clinical Diagnosis in Ophthalmology- Oculoplasty and Reconstructive Surgery. Jaypee Brothers Medical Publishers (P) Ltd 2008. P 20.
Basak Samar K. Atlas of Clinical Ophthalmology Second Edition. Jaypee Brothers Medical Publishers (P) Ltd 2013. P 6.
Wright Kenneth W, Spiegel Peter H. Pediatric Ophthalmology and Strabismus Second Edition. Springer Science+ Business Media New York 2003. P 301.
Katowitz James A. Pediatric Oculoplastic Surgery. Springer Science+Business Media New York 2002. P 213- 214.
Tasman William, Jaeger Edward A. The Wills Eye Hospital Atlas of Clinical Ophthalmology Second Edition. Lippincott Williams & Wilkins 2001. P 370.
Nelson Leonard B, Olitsky Scott E. Harley’s Pediatric Ophthalmology Fifth Edition. Lippincott Williams & Wilkins 2005. P 372.
Lambert Scott R, Lyons Christopher J. Taylor & Hoyt’s Pediatric Ophthalmology and Strabismus Fifth Edition. Elsevier Inc. 2017. P 176.
Traboulsi Elias I. Genetic Diseases of the Eye. Second Edition. Oxford University Press 2012. P 46- 47.
Olitsky Scott E, Nelson Leonard B. A Color Handbook – Pediatric Clinical Ophthalmology. Mansion Publishing Ltd. 2012. P 188.
Fay Aaron, Dolman Peter J. Diseases and Disorders of the Orbit and Ocular Adnexa. Elsevier Inc. 2017. P 147- 148.
Bowling Brad. Kanski’s Clinical Ophthalmology- A Systematic Approach Eighth Edition. Elsevier Limited 2016. P 61.
Kaiser Peter K, Friedman Neil J, Pineda Roberto. The Massachusetts Eye and Ear Infirmary- Illustrated Manual of Ophthalmology Fourth Edition. Elsevier Saunders 2014. P 100.
Wright Kenneth W, Strube Yi Ning J. Pediatric Ophthalmology and Strabismus Third Edition. Oxford University Press 2012. P 587.
Adam MP, Hudgins L. Kabuki syndrome: a review. Clin Genet 2005;67: 209- 219.
Gorlin RJ, Zellweger H, Curtis MW, et al. Blepharo-cheilo-dontic (BCD) syndrome. Am J Med Genet 1996;65: 109- 112.
Desmarres LA. “Traité théorique et pratique des maladies des yeux”1854 Paris, Vol.1. P 468.
Duke-Elder S. “System of Ophthalmology” 1964 Kimpton, London. Vol. 3, part 2. P 841.
Duke-Elder S, Cook C. Idem 1963, Vol. 3, Part 1. P 310.
Euryblepharon may be unilateral or bilateral. It may present with
Enlargement of horizontal palpebral apertures.
Elongated lid margins.
Downward and lateral displacement of outer canthus.
Watering or epiphora.
Reduced blink rate.
Euryblepharon may be inherited as an autosomal dominant disorder or may occur sporadically.
A variety of systemic conditions may be associated such as
Kabuki syndrome: Kabuki syndrome, described in 1981, is an idiopathic multisystem disorder characterised by characteristic facial features, short stature, mental retardation, and skeletal abnormalities. This is a clinical diagnosis of uncertain aetiology. Most cases are sporadic, but multiple familial cases suggest autosomal dominant inheritance. Clinical features include euryblepharon, depressed nasal tip, prominent cupped ears and arched eyebrows. Other ocular abnormalities may also be present. Systemic abnormalities include cleft lip/palate, kidney or urinary tract anomalies, and cardiovascular disorders.
Blepharo-cheilo-dontic (BCD) syndrome: This congenital condition is characterised by euryblepharon with ectropion of the lower eyelids, cleft lip/palate, and dental anomalies (oligodontia and conical teeth). Other ocular abnormalities reported with this disorder are lagophthalmos, ectropion, distichiasis, and ocular hypertelorism (widely apart orbits).
Diagnosis of euryblepharon is based on clinical features.
Euryblepharon presents with
Bilateral symmetrical enlargement of the horizontal palpebral apertures.
Elongated lid margins. The horizontal palpebral fissure length is increased to approximately 35 mm. from the average length of 28- 30 mm.
Vertical shortening of eyelid skin.
Downward and lateral displacement of outer canthi.
There is lateral ectropion, reduced blink rate, lagophthalmos, with exposure keratopathy. There may be epiphora due to exposure and reduced blink rate.
Euryblepharon may be distinguished from conditions such as
Congenital ectropion: Congenital ectropion also has vertical shortening of eyelid skin, but there is no elongation of lid margin.
Lower lid ptosis.
Other causes of epiphora.
Management should be carried out under medical supervision.
Most of the cases do not require any treatment. The condition may cease to be apparent with facial growth.
Mild cases may be managed conservatively by medical means.
Topical lubricant artificial tears: Topical lubricant artificial tears may be used to prevent ocular irritation.
Moderate degrees of euryblepharon may require surgical therapy to protect the cornea. It may involve procedures like
Lateral tarsorrhaphy: Lateral tarsorrhaphy (joining of upper and lower eyelids) may be required for symptomatic cases.
Lateral canthoplasty with shortening of the upper and lower eyelids laterally.
Re-suspension of lateral canthus: Re-suspension of lateral canthus using lateral tarsal strip may be done in severe cases of euryblepharon causing epiphora or exposure keratopathy.
Augmentation of posterior lamella and anterior skin graft, for severe forms of vertical eyelid shortening.
Prognosis of euryblepharon may be excellent if necessary surgery for eyelid mal-position is performed to protect ocular surface.