third eyelid


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pli·ca sem·i·lu·na·'ris of con·junc·ti·'va

[TA]
1. the semilunar fold formed by the palpebral conjunctiva at the medial angle of the eye;
2. a fold of the conjunctival mucous membrane found in many animals; normally partially hidden in the medial canthus of the eye when at rest, it may be extended to cover part or all of the cornea in a winklike action to clean the cornea, as in birds. Synonym(s): membrana nictitans, nictitating membrane, palpebra III, palpebra tertia, third eyelid

third eyelid

References in periodicals archive ?
The sesamoid bone of the sclera, whose function is to redirect the path of the tendon of the third eyelid pyramidal muscle, was described for the first time by MAHECHA & OLIVEIRA (1999) in Strigiformes, showing different dimensions and shapes in the different species studied.
Intranictitans tacking for replacement of prolapsed gland of the third eyelid in dogs.
The sites of the dermoids in that study were reported in decreasing order of incidence as the limbus third eyelid canthus eyelid and conjunctiva (Barkyoumb and Leipold 1984).
Microalterations in the third eyelid gland of dogs with keratoconjuntivitis sicca secondary to distemper.
It involves snipping a tiny piece of lymphoid tissue from the animal's nictitating membrane, or third eyelid, staining it with antibodies, and examining it under a microscope.
Normally the third eyelid is held back by the position of the eyeball, so anything that makes the eyeball shrink slightly or sink back into the head can make the third eyelid more visible.
The birds can see eight times better than humans, and a transparent third eyelid helps keep their eyes clean and moist.
Hockenhull says: "He had cancer on his third eyelid and it was causing him quite a lot of irritation.
I created a third eyelid flap and we all crossed our fingers for a happy outcome.
* ANSWER This sounds like the classic "cherry eye." This is the common name for the prolapse of the gland of the third eyelid. The third eyelid is present between the lower eyelid and globe or eyeball.
Ocular lesions are most common at the medial canthus and may involve the skin, nasolacrmal duct, third eyelid or conjunctiva (Wilkie, 2004; Gasthuys et al, 2004; Pusterla et al, 2003; Yarmut et al, 2008; Pugh et al, 2014).