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 eyel ...
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, and b ...
, but may also occur with
cicatricial
A scar (or scar tissue) is an area of fibrous tissue that replaces normal skin after an injury. Scars result from the biological process of wound repair in the skin, as well as in other organs, and tissues of the body. Thus, scarring is a nat ...
changes to the eyelid or congenital
ptosis. Lid lag differs from
Von Graefe's sign
Von Graefe's sign is the lagging of the upper eyelid on downward rotation of the human eye, eye, indicating exophthalmos, exophthalmic Goitre, goiter (Graves' disease).Cline D; Hofstetter HW; Griffin JR. ''Dictionary of Visual Science''. 4th ed. Bu ...
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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