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Congenital Anomalies of the Eyelid, Orbit, and Lacrimal System
Forrest J. Ellis, MD
The development of the lacrimal drainage system begins at approximately 6 week's gestation. Canalization of the ectodermal cord begins during the third month in the area of the medial canthus. Canalization progresses toward the eyelid margin and toward the inferior meatus. The lacrimal puncta normally opens with eyelid separation during the seventh month of gestation. The distal lacrimal drainage system may not become patent until birth or shortly after birth. Blockage of the nasolacrimal system typically occurs in the distal portion where the tear duct opens into the nose beneath the inferior turbinate (Hasner valve). Because tears are not normally produced until a few weeks after birth, blockage of the lacrimal duct may not be recognized until several weeks after birth. Only about 1% to 6% of infants have symptomatic nasolacrimal duct obstruction.1,2 However, the majority of cases resolve by 1 year of age.3,4
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The child with congenital nasolacrimal duct obstruction has a history of unilateral or bilateral epiphora (Slide 1). Tearing may be worse with upper respiratory tract infections or with exposure to wind or cold. Tears may dry on the lashes during sleep causing the eyelids to stick together in the morning or after the child takes a nap. Infectious conjunctivitis is not uncommon. Photophobia is not usually present in children with blocked tear ducts and should raise suspicion for congenital glaucoma or ocular surface disease.
The differential diagnosis of tearing includes congenital glaucoma, surface abnormalities of the cornea, entropion, epiblepharon trichiasis, and distichiasis. Significant craniofacial abnormalities causing mal-development in the area of the nasolacrimal system including encephaloceles and facial clefts may preclude normal development of the nasolacrimal system.
The office examination of a tearing infant should pay specific attention to the area of the external adnexa including the position or malposition of the eyelids and lashes. An abnormal widening of the inner canthal region suggests a midface abnormality. The corneal diameter should be measured and the cornea evaluated for clarity and for evidence of surface disease. The puncta should be inspected for patency. Pressure over the lacrimal sac may discharge mucopurulent material into the lacrimal lake. When this finding is present, it confirms that the upper system is patent and the lower lacrimal system is blocked. Because pediatricians are aware that congenital nasolacrimal duct obstruction often resolves spontaneously, the child may not be referred to an ophthalmologist until 12 months of age. Massage of the nasolacrimal sac to increase the hydrostatic pressure in the distal duct has been shown to help open the nasolacrimal duct.5,6
A simple test that can be performed in the office is the dye disappearance test.7 A drop of fluorescein dye in either solution or a strip in combination with a topical anesthetic is applied to the lower conjunctival cul-de-sac bilaterally. Excess fluorescein on the cheek is wiped away. The parents are instructed not to wipe the eyes. After 5 minutes, the eyes are inspected for residual fluorescein in the tear film with the blue light of the slit lamp. Failure to clear most of the dye from the tear film within this time frame is suggestive of nasolacrimal duct obstruction.
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The management of congenital nasolacrimal duct obstruction is not universally agreed upon. Children with recurrent infections may benefit from probing within the first 6 months of life. However, conservative measures such as massage often assist in the spontaneous resolution of the obstruction within the first year of life. Probing may be performed in the office or in the operating room. Probing is typically performed in conjunction with irrigation of the tear ducts at or before 13 months of age.8 If only a unilateral obstruction is present, the contralateral tear duct may be investigated with irrigation alone. If the inferior turbinate presents a significant obstruction to the opening of the nasolacrimal duct, then infracture of the turbinate can be carried out at the time of either the primary procedure or any subsequent secondary procedures. If probing and irrigation fail to resolve the tear duct obstruction, then silicone tubes may be placed as a secondary procedure. An alternative to probing is balloon catheter dilation.9,10 Only in situations in which drainage to the normal lacrimal system is unable to be obtained is more aggressive intervention such as a dacryocystorhinostomy required.11
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A lacrimal sac dacryocele (mucocele) is typically present at birth. This bluish mass in the area of the lacrimal sac results from a buildup of mucoid fluid in the lacrimal sac (Slide 2). Distal nasolacrimal obstruction is always present. Although mucoceles may respond to massage, early probing is recommended because of the risk of dacryocystitis (Slide 3). Expansion of the distal duct may result in an intranasal cyst that can result in obstruction of the nasal passages.12 Bilateral cases may lead to respiratory distress because infants are obligate nasal breathers.
Imperforate puncta are occasionally responsible for overflow tearing. Often, the canaliculus is just beneath the skin. A punctal dilator or small-gauge needle may open the punctum. A probing of the nasolacrimal system should then be performed to assess the patency of the entire system. Accessory lacrimal ducts and fistulas may cause tears and mucoid discharge from the skin beneath the lower eyelid. These fistulas usually connect directly to the lacrimal sac. Excision of the entire fistula down to the lacrimal sac reduces the chance of recurrence.
Cryptophthalmus occurs when the lid folds fail to develop. The skin over the eye is continuous from the forehead to the cheek, and the eyelashes and glands are partially or completely absent. Ocular development is abnormal and visual rehabilitation is not expected. Cosmetic reconstruction with mucous membrane grafting to form conjunctival fornices may allow conformer placement. Cryptophthalmus occurs in sporadic and recessive inheritance patterns. Bilateral cases are more frequent than unilateral cases.
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Eyelid colobomas fall into the spectrum of clefting syndromes. Colobomas of the eyelid result from inadequate fusion of the embryonic lid folds and always have a defect in the eyelid margin (Slide 4). Proper development of the adnexal structure of the eyelid, including the tarsus glands and cilia, require normal eyelid fusion to develop. Therefore, lid colobomas characteristically have absence of the tarsus as well as the adnexal structures. Pseudocolobomas occur when the outer portion of the lower lid is pulled downward. There is not a defect in the eyelid margin. This may be part of a general facial clefting syndrome. It may also be seen in conjunction with Treacher Collins syndrome or Goldenhar syndrome.
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Colobomas are most frequently seen in the nasal aspect of the upper lid. They may vary in severity from a small notch in the eyelid margin to a near complete absence of the lid. Examination for associated anomalies including limbal dermoids, dermatolipoma, microphthalmos, ocular colobomas, and facial clefts should be performed.
The repair of eyelid colobomas is performed to correct the functional and cosmetic problems. Management involves lubrication to protect the corneal surface. A delayed repair until 6 to 12 months of age is desirable because growth of the tissues allows easier mobilization of flaps. Depending on the size of the defect, the timing and type of surgical repair may vary. Small colobomas of less than 25% of the lid margin may be closed primarily by excision of the defect in a pentagonal manner. Larger defects of 25% to 40% of the lid margin may require a lateral canthotomy and cantholysis. If this fails to mobilize enough tissue for closure, a semicircular flap can be created. Generally, lid-sharing procedures are to be avoided in children in the amblyopic age range.
Ankyloblepharon results from failure of the eyelid margins to separate (Slide 5). This may be complete or incomplete with fine strands between the upper and lower eyelids. When multiple fine strands between the upper and lower eyelid occur, the condition is referred to as ankyloblepharon filaform. These fine bands may be simply cut. When the fusion is more complete, the lids should be separated and the eyelid margins reconstructed by suturing the conjunctiva over the posterior eyelid margin to the anterior skin surface.
Distichiasis describes an extra row of aberrant lashes near the orifices of the meibomian glands. If the lashes contact the cornea, tearing and discharge may occur. These cilia are typically fine. Electrolysis is difficult to perform on an infant and split thickness resection or cryosurgery may be used for removal of the abnormal cilia.13
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Epiblepharon describes a horizontal fold of skin along the lower eyelid (Slide 6). This fold of skin mechanically pushes the lashes inward against the cornea. Epiblepharon is most common in an Asian infant's eyelid and usually resolves with maturation and growth of the face. Most children with epiblepharon do not require treatment or can be managed with lubrication until the condition resolves. Rarely, significant corneal irritation necessitates surgical correction. A small ellipse of skin and orbicularis inferior to the eyelid margin is excised and closed primarily. Care should be taken to avoid excess skin removal resulting in lower eyelid retraction.
Entropion is an inward turning of the eyelid margin and is usually seen in the lower eyelid. This occurs most commonly with poor posterior support to the lower eyelid as occurs with microphthalmos. Other causes include tarsal abnormalities, hypertrophy of the orbicularis muscle, and abnormalities in the lower eyelid retractors. Although mild cases may be tolerated, persistent corneal irritation necessitates repair.
Repair may be undertaken in much the same way as the repair for epiblepharon. A small ellipse of skin and orbicularis underlying the eyelid margin is removed. However, the lower eyelid retractors should be re-opposed and possibly advanced on the lower tarsus.
Congenital ectropion occurs when the eyelid margin is rolled away from the surface of the globe. This rare condition usually involves the lower eyelid. It may be seen as part of the blepharophimosis syndrome. Initial treatment includes lubrication. Exposure keratopathy may necessitate surgical repair. Surgical repair involves horizontal shortening combined with a lateral canthal refixation.14
Infection should be considered in the differential diagnosis of ectropion, especially when the upper eyelid is involved. Appropriate culture and management of any associated infection should be addressed prior to contemplation of surgical repair.
Euryblepharon is an abnormal position of the lower lid where the eyelid does not oppose the lateral aspect of the globe and conjunctiva. This condition usually does not require treatment but can be seen as part of many syndromes. Euryblepharon is often mistaken for congenital ectropion.
Epicanthal folds are folds of skin in the medial canthal region. These can be seen in several syndromes including Down syndrome and blepharophimosis syndrome. Epicanthal folds often lead to referral to the ophthalmologist because of pseudoesotropia. Epicanthal folds are generally classified into four types 15: epicanthus supraciliaris, epicanthus palpebralis, epicanthus tarsalis, and epicanthus inversus. Epicanthus supraciliaris describes a fold arising in the region of the eyebrow and ending over the lacrimal sac. Epicanthus palpebralis is a fold running from the upper eyelid tarsal area to the lower border of the orbit. Epicanthus tarsalis involves a fold of skin from the upper lid tarsal region to the area of the medial canthus. It is common in the Asian eyelid. Epicanthus inversus describes a fold of skin primarily from the lower eyelid usually ending on the upper eyelid. Epicanthus inversus occurs in conjunction with ptosis, and as part of the blepharophimosis syndrome.
Repair of epicanthal folds may be performed to improve the cosmetic appearance or improve the medial visual field in severe cases. A variety of techniques including a V-Y plasty, the Mustarde technique, or the Roveda procedure may be used.
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Blepharophimosis syndrome is a congenital syndrome of ptosis, blepharophimosis (narrowing of palpebral fissure in both the vertical and horizontal dimension), epicanthus inversus, and telecanthus (Slide 7). Lower eyelid ectropion may be seen in this condition. Blepharophimosis syndrome is autosomal dominant. Ptosis in blepharophimosis syndrome is typically associated with poor levator muscle function and, as a result, a frontalis suspension ptosis repair is usually required. One may elect to repair the telecanthus with transnasal wiring or medial canthal tendon plication. Epicanthal folds are repaired as described previously. Repair of telecanthus and epicanthal folds may affect eyelid levels and, therefore, ptosis repair should be delayed until after medial canthal surgery.
Anophthalmos and Microphthalmos
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Anophthalmos results from abnormal development of optic vesicle. True anophthalmos is extremely rare. Differentiation from severe microphthalmos can only be made with serial histologic sections through the orbit. For this reason, the term clinical anophthalmos is used. Microphthalmos refers to a small eye in the range between a normal sized eye and true anophthalmia (Slide 8). Microphthalmos is often seen in conjunction with coloboma. In addition, a cyst may form in the inferonasal area and protrude through the lower lid (Slide 9).
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Microphthalmos may be unilateral or bilateral and sporadic or inherited. Anophthalmos and microphthalmos are associated with hypoplasia of the orbital bones. The management of severe microphthalmos or anophthalmos involves use of conformers to increase the size of the orbit and to expand the palpebral fissures. Conformers require frequent modification, especially during the first several months of life. Conformers should be initiated soon after birth. The conformers should be designed to place both horizontal and vertical pressure on the eyelids. In addition, posterior pressure enlarges the socket. The pressure of the conformer will stimulate orbital bone growth. Dermal fat grafts can be used to augment the volume and, with growth, the orbit can be expanded further. Removal of the severely microphthalmic eye is usually not required. Canthotomy and canthoplasty may enlarge the palpebral opening. Mucous membrane grafting to increase the conjunctival fornices may be necessary. However, because scarring may limit future eyelid expansion, early surgery is usually not recommended.
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Dermoids represent remnants of ectodermal tissues. Three types occur, the dermoid cyst, the epibulbar dermoid, and the dermolipoma.
Dermoid Cyst
Dermoid cysts are ectodermal elements located in a subcutaneous location along the lines of fetal sutures
(Slide 10). The wall of the cyst surrounds adnexal skin elements with an inner content of keratin and
epidermal debris. Dermoid cysts of the periorbital area are common. The most common location is the
superotemporal orbit at the frontozygomatic suture. Orbital dermoids also occur in the superior medial
orbit at the frontonasal suture. On computed tomography (CT), dermoids appear as a well-defined mass
that does not enhance. Rupture of a dermoid cyst results in inflammation that may cause ptosis and strabismus.
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Epibulbar Dermoid
Epibulbar dermoids may be seen in association with Goldenhar syndrome or may occur as an isolated finding.
Epibulbar dermoids are typically located at the temporal limbus but may extend onto the cornea (Slide 11).
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Dermolipoma
Dermolipomas are fatty tumors that are typically found subconjunctivally in the superior lateral fornix
(Slide 12). These tumors are frequently associated with Goldenhar syndrome. Histologically,
dermolipomas consist of stratified squamous epithelium and adipose tissue. Dermolipomas are usually
intermixed with the lacrimal gland and the extraocular muscles. The mass is usually covered by the eyelid
and not casually noticeable. If excision of a larger lesion for cosmetic reasons is planned, only the most
anterior portion of the lesion should be removed. Extensive debulking often results in dry eye syndrome and permanent strabismus.
Capillary hemangiomas are the most common tumors of the eyelid and orbit in infancy 16 (Slide 13). Superficial lesions have a red irregular surface. Orbital lesions may show a mass effect without superficial skin changes. Capillary hemangiomas are soft and easily compressible. When the skin is involved, the blood blanches with compression. These tumors may grow rapidly during the first year of life. This rapid growth phase is followed by a slow involution lasting until the age of 3 to 7 years.
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Management involves correction of anisometropia and patching when amblyopia is present. For localized lesions, a combination of both long-acting and short-acting intralesional steroids can be used to decrease the rate of growth and induce involution. Cases of retinal artery occlusion have been reported with intralesional steroid use, but fortunately this complication is rare. Skin necrosis and depigmentation of the skin may also occur. More extensive lesions and lesions involving deeper structures may be treated with oral steroids. Both systemic and intralesional steroids may have systemic side effects including growth retardation and adrenal suppression. Oral steroids are often given for several months and tapered slowly prior to discontinuation. The child's growth typically catches up with discontinuation of the steroid. Interferon may inhibit growth of these lesions, but has been associated with spastic diplegia. This complication may be permanent and, therefore, interferon is used for life-threatening lesions that are unresponsive to other treatment modalities. The tunable dye laser can be used to treat superficial hemangiomas. Because this laser only penetrates a few millimeters into the tissue, it is not useful for thicker and deeper lesions.
