7
Table 3. Diagnostic Tests Ordered for Possible Underlying
Systemic Conditions in Patients With Dry Eye
Suspected Underlying
Condition Diagnostic Testing
Sjögren syndrome SSA, SSB, ANA, RF
yroid eye disease Anti-thyroid peroxidase antibody, antithyroglobulin
antibody, B-scan sonogram to assess extraocular muscle
thickness
Sarcoidosis Serum lysozyme, ACE, chest CT to determine extent
of disease (consult with a pulmonologist as necessary),
conjunctival biopsy
Cicatricial pemphigoid Conjunctival biopsy with light microscopic as well as
immunofluorescent or immunohistochemical studies
ACE, angiotensin-converting enzyme; ANA, antinuclear antibody; CT, computed
tomography; RF, rheumatoid factor; SSA, anti-Sjögren syndrome A antibody (anti-Ro);
SSB, anti-Sjögren syndrome B antibody (anti-La)
Table 4. Characteristic Findings for Dry Eye Syndrome
Diagnostic Testing
Test Characteristic Findings
Aqueous tear
deficiency
Ocular surface dye staining Pattern of exposure zone
(interpalpebral) corneal and bulbar
conjunctival staining typical
Tear break-up time <10 seconds considered abnormal
Aqueous tear production
(Schirmer test)
≤10 mm for Schirmer test with
anesthesia considered abnormal
Fluorescein clearance test/
tear function index
Test result is compared with a standard
color scale
Lacrimal gland function Decreased tear lactoferrin
concentrations
Tear osmolarity Possibly increased with unclear clinical
implications
Evaporative tear
deficiency
Ocular surface dye staining Staining of inferior cornea and bulbar
conjunctiva typical
Tear break-up time <10 seconds considered abnormal
Tear osmolarity Possibly increased with unclear clinical
implications
