Marcus Gunn phenomenon
| Marcus Gunn phenomenon | |
|---|---|
| Other names | Marcus Gunn jaw-winking or Trigemino-oculomotor synkinesis |
| Nerves of the orbit, and the ciliary ganglion. Side view. (Trigeminal nerve and oculomotor nerve both visible) | |
| Specialty | Ophthalmology neurology |
Marcus Gunn phenomenon is an autosomal dominant condition with incomplete penetrance, in which nursing infants will have rhythmic upward jerking of their upper eyelid. This condition is characterized as a synkinesis: when two or more muscles that are independently innervated have either simultaneous or coordinated movements.[1][2]
Common physiologic examples of synkineses occur during sucking, chewing, or conjugate eye movements. There are also several abnormal cranial nerve synkineses, both acquired and congenital. Marcus Gunn jaw-winking is an example of a pathologic congenital synkinesis.
First described by the ophthalmologist Marcus Gunn in 1883,[3] this condition presents in approximately 5% of neonates with congenital ptosis. This condition has been associated with amblyopia (in 54% of cases), anisometropia (26%), and strabismus (56%).
- ^ Yamada K, Hunter DG, Andrews C, Engle EC (September 2005). "A novel KIF21A mutation in a patient with congenital fibrosis of the extraocular muscles and Marcus Gunn jaw-winking phenomenon". Arch. Ophthalmol. 123 (9): 1254–9. doi:10.1001/archopht.123.9.1254. PMID 16157808.
- ^ Cates CA, Tyers AG (2008). "Results of levator excision followed by fascia lata brow suspension in patients with congenital and jaw-winking ptosis". Orbit. 27 (2): 83–9. doi:10.1080/01676830701376072. PMID 18415867. S2CID 23268883.
- ^ Gunn RM. Congenital ptosis with peculiar associated movements of the affected lid. Trans Ophthal Soc UK. 1883;3:283-7.