2020–2021 BCSC Basic and Clinical Science Course™
5 Neuro-Ophthalmology
Chapter 11: The Patient With Eyelid or Facial Abnormalities
Ptosis
Congenital Ptosis
The most common form of congenital ptosis is thought to result from dystrophic development of the levator palpebrae superioris muscle without associated innervational abnormalities. Congenital ptosis is typically associated with decreased levator function, lid lag on downgaze, and poorly formed (or absent) upper eyelid crease. Congenital ptosis (Fig 11-5) may be unilateral or bilateral and may be associated with other congenital ocular or orbital abnormalities, including blepharophimosis syndrome, congenital fibrosis of the extraocular muscles, superior rectus weakness or overaction, and Marcus Gunn jawwinking syndrome (Fig 11-6). This last phenomenon is a synkinetic movement of the eyelid associated with jaw movement. In the external pterygoid–levator form of the syndrome, the eyelid elevates with movement of the mandible to the opposite side, jaw protrusion, or wide opening of the mouth. With the internal pterygoid–levator form, the eyelid elevates when the teeth are clenched. In some patients with Marcus Gunn jaw-winking syndrome, ptosis may worsen with movement of the jaw, although this finding is not common. Congenital tumors, such as hemangiomas and neurofibromas (see Fig 11-1) may also lead to congenital ptosis. Such tumors are typically associated with a palpable mass. Congenital CN III palsy and congenital Horner syndrome are relatively rare causes of congenital neurogenic ptosis. Whatever the origin of a child’s congenital ptosis, the ophthalmologist must be aware of the potential for amblyopia as a result of occlusion or anisometropia.
Excerpted from BCSC 2020-2021 series: Section 5 - Neuro-Ophthalmology. For more information and to purchase the entire series, please visit https://www.aao.org/bcsc.