Lid lag is the static situation in which the upper
eyelid
An eyelid is a thin fold of skin that covers and protects an eye. The levator palpebrae superioris muscle retracts the eyelid, exposing the cornea to the outside, giving vision. This can be either voluntarily or involuntarily. The human eye ...
is higher than normal with the
globe in downgaze.
It is most often a sign of
thyroid eye disease
Graves’ ophthalmopathy, also known as thyroid eye disease (TED), is an autoimmune inflammatory disorder of the orbit and periorbital tissues, characterized by upper eyelid retraction, lid lag, swelling, redness ( erythema), conjunctivitis, an ...
, but may also occur with
cicatricial changes to the eyelid or congenital
ptosis. Lid lag differs from
Von Graefe's sign in that the latter is a dynamic process. It can also be the manifestation of chemosis (swelling (or edema) of the conjunctiva).
References
Eye diseases
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