[Tear film analysis and its relation with palpebral fissure height and exophthalmos in Graves' ophthalmopathy].

PURPOSE To evaluate tear film quality by rose bengal staining and its stability by breakup time, relating with palpebral fissure height and exophthalmos in patients with Graves' ophthalmopathy. METHODS We studied 54 eyes of 27 patients with Graves' ophthalmopathy, either in the inflammatory or in the chronic phase of the disease. The evaluation consisted of tear film qualitative analysis by rose bengal staining using the van Bijsterveld grading scale, tear film stability analysis by breakup time, measurement of palpebral fissure height and exophthalmometry. Qui square test was used to perform statistical analysis. RESULTS Among 27 studied patients, 77.8% were females and 22.2% males. Mean age was 44.26 years (SD 12.67). Mean disease time was 5.85 years (SD 4.47) and mean ophthalmopathy time was 5.81 years (SD 5.37). Among 54 studied eyes, 37% had positive test by van Bijsterveld's grading scale, 33.3% tear film breakup time lower than 5 seconds, 57.4% palpebral fissure height greater than 11 mm and 55.6% exophthalmometry greater than 19 mm. When relating tear film breakup time lower than 5 seconds with palpebral fissure height greater than 11 mm we found an odds ratio of 11.2 (p=0.0008). The remaining relationships did not show statistical significance. CONCLUSIONS Dry eye diagnosed by rose bengal staining and tear film breakup time occurs frequently in Graves' ophthalmopathy. Palpebral fissure height correlates with tear film breakup time in Graves' ophthalmopathy. Its increase may lead to tear film instability.