Abstract
Abstract: :
Purpose: Although the NEI/Industry working group recommended use of a validated symptomatology questionnaire in dry eye, there are concerns with several of the current survey instruments. We further modified an efficient, previously validated questionnaire to make it quantitative and characterized it in a group of mild-moderate dry eye subjects. Methods: The six-question instrument developed by Schein and co-workers (Ophthalmol.,104:1395, 1997) was modified by adding a category of "never" for frequency and giving each of the five possible frequency responses a numerical value of 0-4. Forty-nine subjects were screened for dry eye using the modified instrument and a battery of noninvasive (e.g., lipid interferometry and NIBUT, meniscus height) and invasive (e.g., TBUT, fluorescein and rose bengal staining, Schirmer I) tests. Measures for dry eye diagnosis used three of the four NEI/Industry working group recommendations: symptoms, tear instability and surface damage (Lemp M, CLAO J, 21:221, 1995). Specific dry eye diagnostic criteria were any symptoms, TBUT < 10 secs, and for surface damage either fluorescein staining > 2 (0-4 score/zone, NEI fine zone system) OR rose bengal staining > 2 (0-4 score/zone, NEI six zone system). A sub-set of 18 subjects with atrophic meibomian gland disease (MGD) were given the questionnaire on a second visit to assess repeatability. Results: 32 of the 49 subjects screened were classified as dry based on the above diagnostic criteria. Of the dry eye subjects, "dryness" demonstrated the highest numerical mean score (2.63 ± 0.9), followed in order by "redness" (2.06 ± 1.1), "burning" (2.03 ± 1.1) and "grittiness" (1.94 ± 1.1), with "crusting " and "stuck shut upon awakening" scoring < 1.0. The overall score for the dry subjects (mean 10.22 ± 3.3) was not significantly different compared to the normals (mean 8.76 ± 3.2; Student t test, p =0.072, one-tailed). The atrophic MGD subgroup of 18 subjects demonstrated an overall apparent increase in total score (mean at second visit = 11.17 ± 2.9 vs. mean at first visit = 9.83 ± 2.5; p = 0.008, Wilcoxon Signed Rank Test, two-tailed). However, the increase in total score was likely due to increased scores for questions 4 (redness) and 5 (crusting). The overall severity for these dry eye subjects was mild- to moderate, with no severe cases included. Conclusions: The modified Schein questionnaire is efficient and may be useful in discriminating normal patients from those with ocular dryness. However, further optimization of the questions and validation using additional dry eye sub-types appears necessary to further improve efficacy.
Keywords: cornea: tears/tear film/dry eye • clinical research methodology • cornea: clinical science