Examination of the Cornea
The cornea is examined with a point light source and a loupe (Fig. 1.10). The cornea is smooth, clear, and reflective. The reflection is distorted in the pres-ence of corneal disorders. Epithelial defects, which are also very painful, will take on an intense green color after application of fluorescein dye; corneal infiltrates and scars are grayish white. Evaluating corneal sensitivity is also important. Sensitivity is evaluated bilaterally to detect possible differences in the reaction of both eyes. The patient looks straight ahead during the exami-nation. The examiner holds the upper eyelid to prevent reflexive closing and touches the cornea anteriorly (Fig. 1.11). Decreased sensitivity can provide information about trigeminal or facial neuropathy, or may be a sign of a viral infection of the cornea.