Congenital Levator Synkinesis: Clinical Spectrum, Pathophysiology, and Surgical Management.

Congenital levator synkinesis represents a complex spectrum of neurodevelopmental disorders characterized by involuntary coupling of eyelid movement with activation of extraocular or masticatory muscles. This review proposes a clinical classification of levator synkinesis into excitatory, inhibitory, and combined phenomena, based on whether synkinetic input results in eyelid elevation, depression, or a combination of both. The underlying pathophysiology is most consistent with a developmental dysinnervation process, likely involving aberrant neural connectivity "miswiring" or, supranuclear release of latent primitive pathways. Histopathologic evidence further supports a neurogenic etiology rather than primary myopathy. Surgical management, largely derived from experience with Marcus Gunn jaw-winking syndrome remains individualized and debated, ranging from levator-disabling procedures with frontalis suspension to more conservative levator-preserving approaches. Recognition of these entities is essential for accurate diagnosis, differentiation from simple congenital ptosis and acquired mimics, and appropriate surgical planning.