Last updated: October 13, 2014
Description: The Schirmer test is a simple, crude measure of ocular tear for- mation and is useful in evaluating patients with dry eye symptoms.
Method: Standardized, commercially available strips of filter paper are folded 5 mm from the end (usually indicated by a notch), and the short end of the fold is placed inside the lower palpebral-conjunctival sac. Normal tear formation spontaneously wets this strip, which will extend downward (at least 15 mm from the eyelid) over a 5-minute period. For most normal individuals, this amount of wetting actually occurs in far less than the suggested time. Less than 15 mm of wetting suggests deficient tear formation. This test is most commonly carried out by an ophthalmologist, although other physicians may perform it at the bedside or in the clinic if the calibrated Schirmer strips are available.
Abnormal in: Moistening <5 mm of filter paper is consistent with Sjögren’s syndrome and keratoconjunctivitis sicca. A positive Schirmer test result suggests, but is not diagnostic of, keratoconjunctivitis sicca and should be confirmed with a rose bengal dye test. Moistening of 5 to 10 mm is equivocal and may require further testing.
Indications: The Schirmer test is used for evaluation of suspected Sjögren’s syndrome or dry eye syndrome (owing to, e.g., medications, blepharitis, allergies, autoimmune disorders).
Cost: Schirmer strips can be purchased for less than $20.
Comment: Patients should discontinue artificial tear use before the procedure. Although topical anesthetic is not required for this test, some patients may find the strip uncomfortable in the eye unless an anesthetic is used. More sensitive measures of tear formation include fluorescein dye staining and rose bengal staining.