A drooping eyelid is called ptosis or blepharoptosis. In ptosis, the upper eyelid falls to a position that is lower than normal. Severe ptosis may cover part or all of the pupil and interfere with vision, resulting in amblyopia.[1, 2] Note the images below:
View Image | Chin-up posture due to congenital ptosis of the left eye. |
View Image | Congenital ptosis of the left eye partially obstructing the left pupillary axis. |
View Image | Congenital ptosis of the right eye. |
Ptosis can affect one eye or both eyes and can present at birth or be more apparent later in childhood. Ptosis that is present at birth or within the first year of life is called congenital ptosis. Most cases of congenital ptosis are isolated and do not affect vision, but refractive errors and amblyopia should always be excluded. Any ptosis that develops over a period of days or weeks can signal a serious medical problem and needs further neurologic and physical evaluation.
The eyelids are elevated by the contraction of the levator palpebrae superioris.
In most cases of congenital ptosis, a droopy eyelid results from a localized myogenic dysgenesis. Rather than normal muscle fibers, fibrous and adipose tissues are present in the muscle belly, diminishing the ability of the levator to contract and relax. Therefore, the condition is commonly called congenital myogenic ptosis.
Congenital ptosis can also occur when the innervation to the levator is interrupted through neurologic or neuromuscular junction dysfunction. Some forms of congenital ptosis may represent a form of congenital cranial dysinnervation disorder.[3]
United States
The frequency of congenital ptosis in the United States has not been officially reported. However, in approximately 70% of known cases, congenital ptosis affects only one eye.
International
The incidence rate of congenital ptosis worldwide is unknown.
If congenital ptosis obscures any part of the pediatric patient's visual field, surgery must be performed to correct the problem early in life. Otherwise, a permanent loss of vision may occur as a result of amblyopia. Note the following:
Congenital ptosis occurs equally among the different races.
Congenital ptosis occurs equally between males and females.
Congenital ptosis is usually present at birth but may manifest within the first year of life.
The repair of congenital ptosis can produce excellent functional and cosmetic results.
With careful observation and treatment, amblyopia can be treated successfully.
Of patients who require surgical intervention, 50% or more may require repeat surgery in 8-10 years following the initial surgery.
Although not all patients with congenital ptosis need surgical intervention, patients need to be closely monitored for the possible development of deprivational amblyopia. Since amblyopia may not be reversed after age 7-10 years, appropriate and timely medical and surgical treatment of congenital ptosis is critical to preserve the child's vision.
Uncorrected congenital ptosis can result in amblyopia secondary to deprivation or uncorrected astigmatism.
An abnormal eyelid position can have negative psychosocial effects.
Uncorrected acquired blepharoptosis results in decreased field of vision and frontal headaches.
All pediatric patients presenting with either unilateral droopy eyelid or bilateral droopy eyelids need a thorough examination that includes a medical history, a family history, a history of drug or allergic reactions, and a review of systems.
Family photographs can help determine onset or variability of the ptosis and the eyelid appearance of family members. A patient with a strong family history of congenital ptosis may not need an extensive workup.
Prior to eyelid surgery, bleeding diathesis, anticoagulant medications, malignant hyperthermia, and cardiac conditions should be excluded. Patients with ptosis and Kearns-Sayre syndrome or chronic progressive external ophthalmoplegia may also have a cardiac conduction disorder.
Maternal myasthenia or a history of fluctuating ptosis with strabismus may suggest myasthenia gravis in a child.
A careful medical history regarding cancer should be obtained. Metastatic or primary orbital tumors can result in ptosis.
A history of trauma with orbital wall fractures can result in pseudoptosis with enophthalmos. Additionally, third cranial nerve palsy from trauma may result in ptosis.
A history of drug or allergic reactions may be helpful. Allergic reactions can result in eyelid edema and droopy eyelid.
A history of anisocoria and iris heterochromia may be helpful in diagnosing Horner syndrome. Patients with Horner syndrome have ipsilateral ptosis and miosis. Cervical or apical thoracic tumors can cause damage to the sympathetic chain and result in this condition. Neuroblastoma, which is one of the most common childhood cancers, should be ruled out.
A history of dry eyes, intermittent epiphora, or chronic conjunctivitis can indicate a dry eye disorder or corneal surface disease.
All pediatric patients presenting with either unilateral droopy eyelid or bilateral droopy eyelids need a thorough physical evaluation.
In infants, the surgeon should ensure the baby can fixate and follow objects with each eye individually. In children with unilateral ptosis, a chin-up head posture usually suggests that the child can see from both eyes. Visual acuity, refraction, and dilated fundus examination findings should be recorded. The patient should be evaluated for strabismus (misalignment), especially since hypotropia can cause a pseudoptosis.
Serial external photographs of the eyes and the face may be included in the patient's record for documentation.
Children usually maintain a good tear film, but tear function should be evaluated if any doubt exists about the adequacy of tear production. This evaluation would include a slit-lamp examination with fluorescein stain to examine the cornea, tear meniscus, and tear break-up time. Schirmer testing and testing of corneal sensation are not commonly performed in children, but can be considered, when appropriate.
An exophthalmometer can be used to assess relative proptosis or enophthalmos of each eye. In pseudoptosis, a proptosis of the contralateral eye gives the false impression that the normal upper eyelid is droopy.
The pupillary size and the iris color differences between the eyes should be examined for Horner syndrome.
Documentation of the distance of the corneal light reflex from the upper lid margin in millimeters (margin reflex distance 1) is very helpful. The vertical palpebral fissure height with each eye fixating in the distance can also be recorded. Patients with congenital ptosis may have a poorly developed lid crease. The lid position in downgaze should be noted. In congenital ptosis, the ptotic lid appears higher in downgaze.
After the palpebral fissure distance is measured, the levator function should be evaluated. The patient looks downward as a ruler is positioned with a mark adjacent to the upper lid margin. With the examiner's hand eliminating any brow action by the patient, the patient looks upward as far as possible without a change in head position. Lid elevation is measured directly from the ruler and is recorded in millimeters of levator function.
Children with ptosis should be asked to open their mouth or chew to examine for jaw-winking (trigemino-oculomotor synkinesis).
The patient should be examined for Bell phenomenon. The patient closes both eyes tightly as the examiner holds the upper and lower lids apart. If the globe elevates during the forced lid closure, a normal Bell phenomenon is present. This evaluation can help the surgeon to determine the risk of exposure keratopathy following the eyelid surgery.
The eyelids should be everted with palpation of the ocular adnexal tissues. A lid mass can cause extra weight in the lid, resulting in ptosis. Plexiform neuromas, lymphoma, or leukemia can result in an eyelid mass, proptosis, or globe displacement. Rhabdomyosarcoma may present with a mass that is palpable through the lid.
In most cases of congenital ptosis, the cause is idiopathic.
Histologically, the levator muscles of patients with congenital ptosis are dystrophic. The levator muscle and aponeurosis tissues appear to be infiltrated or replaced by fat and fibrous tissue. In severe cases, little or no striated muscle can be identified at the time of surgery. This suggests that congenital ptosis is secondary to local developmental defects in muscle structure, and there may be fatty degeneration.[4]
Congenital ptosis may occur through autosomal dominant inheritance. Common familial occurrences suggest that genetic or chromosomal defects are likely.
Note the following causes:
If myasthenia gravis is suspected, check serum acetylcholine receptor antibody levels.[6]
The following are indications to perform neuroimaging studies (eg, MRI, CT) of the orbit and brain:
If myasthenia gravis is suspected, sleep ice test, edrophonium testing, and single-fiber electromyography can be considered.
If a mitochondrial disorder is suspected, an ECG is recommended.
Mild cases of congenital ptosis can be observed if there are no amblyopia, strabismus, or abnormal head posture.
Depending on the severity of the congenital ptosis, patients should be monitored every 3-12 months for signs of amblyopia due to congenital ptosis.
External photographs can be helpful in monitoring patients and their head posture. If a child with previous chin-up head posture stops this behavior, amblyopia should be suspected.
To prevent amblyopia, children with severe ptosis should have their lid taped up for several hours of the waking day while awaiting surgical repair. Children with ptosis should also be checked for astigmatism.
Congenital ptosis has physical, functional, and psychological consequences. The method of repair depends on treatment goals, the underlying diagnosis, and the degree of levator function. Although the primary reason for the repair is functional, the lid height, contour, and eyelid crease should be symmetrized, when feasible.[7, 8, 9, 10, 11, 12]
Surgical correction of congenital ptosis can be undertaken at any age depending on the severity of the disease. Earlier intervention may be required if significant amblyopia or ocular torticollis is present. Severe cases of ocular torticollis may delay mobility in infants and toddlers because of the balance problems from extreme chin-up head posture. If intervention is not urgent, surgery is often delayed until age 3-4 years. Waiting until this age allows for more accurate measurements preoperatively.[13]
Surgery for ptosis in patients with a history of dry eyes, seventh cranial nerve palsy, or significant extraocular muscle abnormalities, such as severe Graves ophthalmopathy, double elevator palsy, or progressive external ophthalmoplegia, should be approached with great caution to avoid exposure keratopathy following the surgery.
This procedure is the shortening of the levator-aponeurosis complex through a lid-crease incision. The skin incision is hidden either in the existing lid fold or in a new lid fold created to match that of the contralateral eyelid.
Moderate levator function must be present to offer a chance for correction with a levator resection. If the levator function is greater than 4 mm but less than 6 mm, a levator resection of greater than or equal to 22 mm is recommended. If the levator function is 6-8 mm, a levator resection of 16-18 mm is indicated. If the levator function is greater than 8 mm, a levator resection of 10-13 mm is indicated.
Contraindications: An external levator resection is not indicated when the levator function is less than 4 mm. In such cases, a long-term surgical outcome may result in undercorrection. Poor Bell phenomenon (limited elevation of the eye), reduced corneal sensitivity, or poor tear production can produce exposure keratopathy. Levator-tightening procedures accentuate jaw-winking and lagophthalmos upon downgaze.
This procedure is designed to augment the patient's lid elevation through brow elevation. Frontalis suspension procedures produce lagophthalmos in most cases. Some surgeons may perform a bilateral suspension procedure for severe unilateral congenital ptosis to obtain symmetry.
The procedure is indicated when the levator function is less than 4 mm.
Relative contraindications are poor Bell phenomenon (limited elevation of the eye), reduced corneal sensitivity, or poor tear production, which can produce exposure keratopathy. If surgery is still indicated, these patients need close postoperative follow-up care to avoid corneal exposure, infection, corneal ulcer and amblyopia.
Several materials are available to secure the lids to the frontalis muscles.[14, 15, 16, 17] These materials include the following:
Patients may not be able to close their eyelids during sleep from a few weeks to several months following surgery. Families must be warned of this outcome before the operation. The problem of open lids during sleep improves with time; however, aggressive lubrication is needed to avoid exposure keratopathy.
The upper lid is elevated by removing a block of tissue from the underside of the lid. This tissue includes the tarsus, conjunctiva, and Müller muscle. This procedure is not commonly performed for cases of congenital ptosis.
This surgery is chosen if the eyelid has had a good response to phenylephrine. The conjunctiva and the Müller muscle are marked off, clamped, and sutured. The tissues are resected. Then, the conjunctival layer is closed. This procedure is not commonly performed for cases of congenital ptosis.
Patients with congenital ptosis may have other conditions that need to be addressed. These conditions include amblyopia, strabismus, craniofacial abnormalities, and other neurologic findings. The following consultations may be appropriate depending on the associated findings:
Complications associated with the frontalis suspension procedure for congenital ptosis repair include the following:
Patients who underwent surgery for congenital ptosis are initially monitored every 2-4 weeks for signs of exposure keratopathy, infection, granuloma formation, and overcorrection and undercorrection. External photographic documentation can be helpful in monitoring patients.
Following the surgery, visual acuity, head posture, and refractive error should be carefully monitored. Any residual amblyopia should be treated aggressively.