Examination of the Eyelids and Nasolacrimal Duct

 Examination of the Eyelids and Nasolacrimal Duct

The upper eyelid covers the superior margin of the cornea. A few millimeters of the sclera will be visible above the lower eyelid. The eyelids are in direct con-tact with the eyeball.

Stenosis of the nasolacrimal duct produces a pool of tears in the medialangle of the eye with lacrimation (epiphora). In inflammation of the lacrimalsac, pressure on the nasolacrimal sac frequently causes a reflux of mucus orpus from the inferior punctum. Patency of the nasolacrimal ductis tested byinstilling a 10% fluorescein solution in the conjunctival sac of the eye. If the dye is present in nasal mucus expelled into paper tissue after two minutes, the lacrimal duct is open.

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