Marcus Gunn Jaw-Winking Syndrome
What Marcus Gunn Jaw-Winking Syndrome Is
Marcus Gunn jaw-winking syndrome is a rare condition a child is born with in which the upper eyelid rises or falls with jaw movement. The condition usually affects one eye. Parents often notice the wink during feeding, chewing, or yawning. The affected lid rests lower than the other (ptosis) and briefly jumps upward when the jaw moves.
Marcus Gunn jaw-winking syndrome accounts for 2 to 6 percent of all congenital ptosis cases. The syndrome is uncommon enough that many general pediatricians may see only a few cases over a career. Pediatric ophthalmologists and oculoplastic surgeons are more familiar with the presentation.
The wink is a sudden upward movement of the droopy lid when the child opens the jaw, moves the jaw to one side, or smiles. The movement is often most visible during bottle-feeding or eating. Some children have a subtle wink; others have a dramatic, highly noticeable movement.
Why It Happens
Marcus Gunn jaw-winking syndrome is caused by an abnormal connection between two nerves. Normally, the trigeminal nerve (V3 branch) controls the muscles that move the jaw, and the oculomotor nerve (CN III) controls the muscles that lift the lid. In this syndrome, signals cross over so that jaw movement triggers lid movement. The abnormal connection is present from birth.
The crossed signal can be confirmed on electromyography (EMG), a test that records muscle activity. EMG is not usually needed for diagnosis, because the visible wink with jaw movement is distinctive. EMG can be useful for research or for unusual cases where the diagnosis is not clear.
The abnormal nerve connection usually forms on one side during early pregnancy. Most cases are not inherited and do not run in families. The reason this happens in some children and not others is not fully understood.
The Ptosis Component
The affected lid sits lower than the other at rest because the levator muscle, which normally lifts the lid, did not develop normally. The ptosis component is similar to other types of congenital ptosis. Severity ranges from mild to covering the pupil.
When the ptosis is severe enough to cover the pupil, amblyopia (lazy eye) can develop. Even moderate ptosis can cause astigmatism from the lid pressing on the cornea. Children with Marcus Gunn syndrome need ongoing pediatric eye care to monitor vision development in the affected eye.
Some children tilt the chin up to see under the droopy lid, especially when the wink is not helping them look in that direction. Others learn to use jaw movement as a way to briefly open the lid for a better view. These compensations often resolve after successful surgery.
When to See a Specialist
Parents usually notice the wink within the first few weeks of life, often during feeding. Any baby whose upper lid moves noticeably with jaw activity should be seen by a pediatric ophthalmologist or oculoplastic surgeon. Early evaluation sets up an amblyopia-monitoring plan.
The specialist checks the lid position at rest, measures levator muscle function, watches the wink with different jaw movements, and looks for other eye conditions. Vision testing, though challenging in infants, begins as early as possible. Photographs and video recordings help track the wink over time.
Children with Marcus Gunn syndrome see the eye doctor every few months in infancy and toddler years, then yearly. The goal is to catch amblyopia early, update glasses if needed, and time any surgical intervention optimally. Most children do not need surgery in infancy unless the ptosis is severe.
Treatment Options
Observation is appropriate for mild cases where the ptosis is subtle, the wink is barely noticeable, and vision is developing normally. Many children with mild Marcus Gunn syndrome live without surgery. Regular monitoring makes sure any changes are caught.
If amblyopia develops, treatment with glasses, patching of the stronger eye, or atropine drops is started. These treatments work best when started early, ideally before age 7. Amblyopia treatment may continue alongside any surgical planning for the ptosis and wink.
Surgery for Marcus Gunn syndrome addresses both the ptosis and the wink. Surgical timing is usually age 3 to 5, when the child can cooperate with muscle function testing and when anesthesia is safer. Vision-threatening ptosis may warrant earlier surgery.
Surgical Approaches
The most commonly used technique is bilateral (both-sides) levator excision combined with a frontalis sling on both sides. The surgeon removes the abnormal levator connection on the affected side and places a sling on both sides so that the lids are lifted evenly by the frontalis (forehead) muscle. This approach eliminates the wink in 97 percent of patients and achieves lid position within 1 mm of the other side in 85 to 88 percent of cases.
Some surgeons offer a unilateral approach, operating only on the affected lid. This is less invasive and preserves the unaffected side. The trade-off is that the wink may not be fully eliminated, because the abnormal nerve signal still reaches the remaining levator tissue. Some patients accept this trade-off for a simpler surgery.
The choice depends on how bothersome the wink is, how much lid symmetry matters for the family, and the child's specific anatomy. An experienced oculoplastic surgeon discusses both options with the family. Long-term outcomes are strong with either approach when performed by a skilled surgeon.
What Recovery Looks Like
Children typically go home the day of surgery. Bruising and swelling around the lids is normal for 1 to 2 weeks. Most children return to school within a few days to a week, depending on the procedure. Pain is usually mild and easily managed with acetaminophen.
The lid position settles over 2 to 3 months as swelling resolves. Parents sometimes worry about asymmetry in the early weeks; this usually evens out. The surgeon checks progress at scheduled visits and can plan adjustments if needed.
After frontalis sling surgery, children use the forehead muscle to lift the lid. Most children adapt quickly and begin lifting the lid normally within weeks. Parents may notice the child briefly raising the brow when trying to open the lid; this becomes less visible over time.
Long-Term Outcomes
Children who have successful ptosis correction usually maintain good lid function long-term. Amblyopia treatment, if needed, continues until visual development is complete, typically by age 7 to 9. Most children reach good visual outcomes.
Slings can stretch or loosen over years, and some patients need a revision procedure in adolescence or adulthood. Levator muscle procedures usually hold long-term. Children who had surgery continue to have periodic eye exams to catch any late changes early.
The surgical scars hide in the natural lid crease or brow. By the time a child is an adult, the scars are usually imperceptible. Most patients and families report high satisfaction with the combined improvement in lid position and elimination of the wink.
Questions Families Ask About Marcus Gunn Syndrome
No. The abnormal nerve connection that causes the wink is present from birth and does not resolve without surgery. Some children learn to minimize visible winking by avoiding certain jaw movements, but the underlying connection remains. Surgery is the only treatment that eliminates the wink.
Not every child needs surgery. Observation is reasonable for mild cases with minimal ptosis, good vision development, and a barely noticeable wink. Surgery is usually recommended when ptosis threatens vision, when the wink causes significant social concern as the child grows, or when the family decides improvement is worth the procedure.
Most surgeons recommend age 3 to 5 for elective surgery because the child can cooperate with levator muscle testing and tolerate anesthesia safely. Severe ptosis that blocks the pupil may need surgery earlier to prevent amblyopia. Your surgical team will recommend timing based on your child's specific situation.
A single surgery is often sufficient, but some children need a revision later in life as slings can stretch. About one in five children with any form of congenital ptosis need a revision at some point. The need for revision is discussed as part of long-term planning.
No. Marcus Gunn jaw-winking syndrome is an isolated eye and nerve condition. It does not affect intelligence, development, or overall health. Children with the syndrome reach age-appropriate milestones like other children.
Marcus Gunn syndrome is usually not inherited. Most cases are sporadic, meaning they occur without a clear family pattern. A very small number of cases have occurred in families, suggesting a possible genetic component in those specific families. A genetic counselor can provide personalized information if your family has concerns.
Next Steps for Your Child
If you notice a wink with jaw movement in your baby or toddler, ask your pediatrician for a referral to a pediatric ophthalmologist or an ASOPRS-trained oculoplastic surgeon with pediatric experience. Early evaluation sets up a monitoring plan and prepares your family for any needed intervention.