- Ptosis ( Ptosis is also known as Blepharoptosis. It refers to an eyelid which is droopy. This may cause a loss of vision, especially while reading, headaches, and eyebrow strain) is the medical term for drooping of the upper eyelid, a condition that may affect one or both eyes. ptosis that is present since birth is called Congenital ptosis.
- Congenital Ptosis comprises a group of diseases in which the ptosisis due to a developmental dystrophy of the levator muscle.
- The ptosis may be mild - in which the lid partially covers the pupil; or severe - in which the lid completely covers the pupil.
- Congenital ptosis comprises of a group of cases in which the ptosis is due to a developmental dystrophy of the levator muscle characterized by fibrosis and deficiency and striated muscle fibers.
- The condition may be associated with anisometropia, strabismus and amblyopia.
Features - Marcus Gunn Jaw wink ptosis is an example of synkinesis (an abnormal innervation connecting two groups of normally UNRELATED muscles)
- This causes the eyelid to open (increase in the palbebral fissure) with movements of the mouth
- poor levator function
- higher position of the ptotic eyelid on downgaze.
- Children with significant ptosis may need to tilt their head back into a chin-up position, lift their eyelid with a finger, or raise their eyebrows in an effort to see from under their drooping eyelid(s).
- Marcus Gunn Jaw-wink ptosis does not generally improve with time, but children do tend to learn how to minimize the appearance
Causes - While the cause of Congenital ptosis is often unclear, the most common reason is improper development of the levator muscle. The levator muscle is the major muscle responsible for elevating the upper eyelid.
- Children with Congenital ptosis may also have amblyopia ("lazy eye"), strabismus (eyes that are not properly aligned or straight), refractive errors, astigmatism, or blurred vision. In addition, drooping of the eyelid may result in an undesired facial appearance.
Evaluation of the Patient Concurrent Anatomic Abnormalitites Blepharophimosis may require medial canthal tendon plication5 Physiologic defects such as jaw-winking ptosis may require transection of the levator muscle as well as frontalis suspension. Because of the levator aponeurosis resection, children needs to be performed under general anesthesia, a formula is used to determine the amount of levator aponeurosis resection.
Marcuc-Gunn Jaw-winking Ptosis In 1883 Marcus Gunn reported an unusual type of congenital ptosis with with a peculiar associated movement of the affected lid." Previous authors have reported Marcus-Gunn phenomena to occur in 2 to 13% of patients with "Congenital ptosis . The phenomena is thought to be due to a Congenitalmisdirection of the fifth cranial nerve fibers into a branch of the third cranial nerve that supplies levator muscle. Patients are classified according to the degree of two parameters: - A 3 x 3 matrix is constructed which gives 9 combinations of ptosis (mild, moderate, severe), in jaw-winking (mild, moderate, severe). Different positions of the matrix correspond to one of several operations which are abdicated for the correction of this defect.
- Beard reported 76% of his patients with Marcus-Gunn syndrome had an associated weakness of the superior rectus.
Incidence of amblyopia in patients with Marcus-Gunn jaw-winking ptosis is reported to be approximately 35%. - In a study in 1984 of 64 patients with jaw- winking ptosis, 60% were found to have amblyopia, 60% were found to have strabismus and 25% were found to have anisometropia. Twenty-five percent were found to have a double elevator palsy.
- It has been proposed that the Marcus-Gunn phenomena is secondary to supranuclear etiology. The prevalence of double elevator palsy in this study tends to support the theory of a supranuclear lesion. In this study of 1984, of 71 patients followed for approximately 5 years, they were unable to document any objective improvement in any of their patients1 However, they felt that adults were able to control their lid position in excursion of masquerading their jaw-winking phenomena
.Treatments In general, if the visual axes are not obscured by the ptotic lid, it is best to defer treatment until the child is age 3 or 4. The surgical procedure is determined by the amount of levator function present and the severity of ptosis. Function is typically categorized as poor (less than 4 mm), fear (5 to 7 mm) and good (more than 8 mm). In cases of severe ptosis in less than 2 mm of levator function, suspension of the lid to frontalis muscle is the procedure of choice. - Conjunctival-muellers resection
- Levator resection
- Frontalis sling
- Silicone
- Fascia (autogenous or donor)
- Supramid
- Congenital Ptosis is treated surgically, with the specific operation based on the severity of the ptosis and the strength of the levator muscle.
- If the ptosis is not severe, surgery is generally performed when the child is between 3 and 5 years of age (the "pre-school" years).
- However, when the ptosis interferes with the child's vision, surgery is performed at an earlier age to allow proper visual development.
- Congenital ptosis is most often treated by ophthalmic plastic and reconstructive surgeons who specialize in disease and conditions affecting the eyelids, lacrimal (tear) system, the orbit (bone cavity around the eye), and adjacent facial structures.
- Below are some pictures of a young child who developed a lazy eye from ptosis and had surgery to repair the drooping left upper eyelid.
Patients with Frontalis Sling; Before & After Photographs The idea of the frontalis sling procedure is to transfer the elevating function of the ptotic eyelid to the frontalis muscle. To achieve this, the eyelid is directly suspended to the brow using various materials. in older children with sufficient limb length, the sling material of choice is autogenous fascia lata Supramid suture, Goretex, silicone, or Mersilene mesh may also be used. Because the sling material has little elasticity, a tethering effect on downgaze, Lagophthalmosare expected postoperatively
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