Frutas y hortalizas

Ankyloblepharon

Partial or complete eyelid fusion. Severe forms may be associated with craniofacial abnormalities. Prognosis usually good unless severe associated defects.

• Simple cases treated with incision of skin webs after clamping with hemostat for 10–15 seconds with reapproximation of skin and conjunctiva; severe cases may necessitate major surgical revision.

Blepharophimosis

Tight, foreshortened (vertically and horizontally) palpebral fissures with poor eyelid function and no levator fold. May be sporadic or part of congenital syndrome (AD) with blepharophimosis, blepharoptosis, epicanthus inversus, and telecanthus. Prognosis

depends on extent of syndrome and need for additional surgery. Mapped to chromosome 3q2 (FOXL2 gene).

• Surgery usually is performed at 4–5 years of age to allow nasal bridge to develop fully.

• Congenital syndrome: consider staged oculoplastic repair with medial canthoplasty via Y–V plasty and transnasal wiring, followed by frontalis suspension for ptosis 3 to 4

months later, and finally full-thickness skin graft from periauricular or supraclavicular area.

FIGURE 3-30 Blepharophimosis syndrome demonstrating small palpebral fissures, lack of upper lid folds, ptosis, epicanthus inversus, and telecanthus.

Coloboma

Small notch to full-thickness defect of the eyelid due to incomplete union of frontonasal or maxillary mesoderm at the eyelid margin, usually superonasal and unilateral.

Inferolateral defects are often bilateral and associated with systemic anomalies such as mandibulofacial dysostosis (AD; Treacher Collins syndrome); corneal exposure and

dryness may occur. Small defects (< 25%) have good prognosis; prognosis of medium and larger defects depends on location and associated abnormalities. Associated with

microphthalmos, iris coloboma, and anterior polar cataract.

FIGURE 3-31 Superonasal coloboma of left upper eyelid in a child.

• Topical lubrication with preservative-free artificial tears or ointments up to q1h.

• Surgical repair (delay until preschool age): small defects (< 25%) via pentagonal resection with direct layered closure, medium defects (25–50%) via Tenzel flap with or without lateral cantholysis, large defects (> 50%) via myocutaneous flap or full-thickness lid rotation flap.

• Beware of lid-sharing procedures in children because occlusion amblyopia may result.

Cryptophthalmos

Congenital defects of the first, second, and third wave of neural crest migration leading to abnormal lid and anterior eye structure development, including partial or complete absence of eyebrow, palpebral fissure, eyelashes, and conjunctiva; may have hidden or buried eye with smooth skin stretching from brow to cheek; more posterior orbital structures are usually normal. Prognosis often poor due to underlying structural ocular

defects.

• Treatment focuses on progressive expansion of the understimulated bony orbit to prevent midfacial hypoplasia; multiple surgeries or expanding conformers often are required with eyelid reconstruction.

Distichiasis

Ectopic eyelashes growing posterior to or out of the meibomian gland orifices. May be congenital or acquired (i.e., from chronic inflammation), sometimes hereditary. Lashes are usually shorter, softer, and finer than normal cilia, and may or may not contact the conjunctival and corneal surfaces; usually well tolerated. In congenital distichiasis, the embryonic pilosebaceous units inappropriately develop into hair follicles. Treat if corneal involvement exists, but with caution because treatment can be more damaging than

disease.

• Topical lubrication with preservative-free artificial tears or ointments or bandage contact lens in mild cases.

• Epilation, tarsal fracture surgery, electrolysis, cryotherapy, or laser thermal ablation in more severe cases.

FIGURE 3-32 Distichiasis with lashes originating from meibomian gland orifice.

Epiblepharon

Redundant skin and orbicularis muscle leading to inward rotation of the lower eyelid margins, turning lashes against the globe; usually resolves spontaneously. More common

in Asians. Prognosis excellent even if surgery necessary.

• Conservative treatment in infants, because condition tends to resolve with facial maturation.

• Subciliary myocutaneous excision is extremely effective; care is taken to avoid overexcision with resultant ectropion.

FIGURE 3-33 Epiblepharon of lower eyelid demonstrating upwardly directed lashes.

Epicanthus

Crescentic vertical skin folds in the medial canthal area overlying the medial canthal tendon; usually bilateral. Caused by immature facial bones or redundant skin and underlying tissue. May be most prominent superiorly (epicanthus tarsalis), inferiorly (epicanthus inversus), or equally distributed (epicanthus palpebralis). Epicanthus tarsalis is frequently associated with Asian eyelids, while epicanthus inversus is associated with blepharophimosis syndrome. Good prognosis.

FIGURE 3-34 Epicanthus demonstrating pseudostrabismus. Note vertical skin fold over medial canthal areas.

• If due to facial bone immaturity, delay treatment.

• When treatment required (delay until preschool age), Z-plasty or Y–V plasty often effective; eyelid crease construction may be required.

Euryblepharon

Horizontal widening of the palpebral fissure, often temporally; usually involves the lower eyelid with an antimongoloid appearance due to inferior insertion of the lateral canthal tendon. Patients have a poor blink, poor lid closure, and lagophthalmos with exposure keratitis. Usually good prognosis.

• Topical lubrication with preservative-free artificial tears in mild cases.

• If symptoms severe and corneal pathology exists, full-thickness eyelid resection with repositioning of lateral canthal tendon may be required. If necessary, vertical eyelid lengthening can be achieved with skin grafts.

Microblepharon

Rare, bilateral, vertical foreshortening of the eyelids, sometimes causing exposure and dry eye symptoms; may be related to cryptophthalmos. Usually stable with good

prognosis if no exposure keratitis exists.

• Topical lubrication with preservative-free artificial tears in mild cases.

• Pedicle rotation skin flaps from cheek or brow, eyelid-sharing procedures, or full-thickness skin grafts for severe exposure with a normal globe.

• Beware of lid-sharing procedures in children because occlusion amblyopia may result.

Telecanthus

Increased distance between medial canthi caused by long medial canthal tendons (in contrast to hypertelorism in which the distance between the medial walls of the orbits is increased). Most frequent ocular finding in fetal alcohol syndrome; also associated with

Waardenburg’s syndrome and blepharophimosis syndrome. Good prognosis.

• Transnasal wiring to shorten distance between medial canthi and remove excess medial canthal skin.

FIGURE 3-35 Telecanthus. Note increased distance between medial canthi.