1. Karin Spielmann & Lars Affentranger

2. Study aim To explore, if the sensitivity of the lid margins at the level of the lidwiper decreases with age

3. Anatomy of the Lidwiper Korb et al. 2010

4. Methods Age group 1: 18 to 30 years Age group 2: 50 to 75 years

5. Methods Exclusion criteria: allergy to fluorescein and lissamine green symptoms of dry eye disease: OSDI score ≥ 15.0 Lidwiperepitheliopathy (LWE) grade 1-3 in the region of sensitivity measurement Contact lens wear Eyelid inflammation, meibomian gland dysfunction Cicatrisation at the upper- and/or lower eyelid (lid margin and/or at the tarsal conjunctiva) Any systemic disease as well injury, that may affect the tear film or the the eyelid as well the lid margin and/or the tarsal conjunctiva Pregnancy Any medication that may affect the tear film Use of eye ointment within 30 days prior to commencement of the study Eye drops at the day of the study appointment

6. Methods – Sample Size A priori G- Power Analysis: 1- = 0.8 α= 0.05 = 0.20 Difference of 0.5 cm standard deviation= 1.06 cm Group 1: 72 Subjects between the age of 18 and 30 years. Group 2: 72 Subjects between the age of 50 and 75 years.

7. Methods Procedures Each subject filled in the OSDI questionnaire Preliminary slit lamp investigation with use of fluorescein and lissamine green, for fulfilment of the inclusion criteria Lid margin sensitivity measurement with use of the Cochet- Bonnet Aesthesiometer filament thickness: 0.12 mm on right eyes only Criterion for determination of threshold: when the filament at a certain length was felt by the subject at least two out of the four presentations The tip of the filament was brought perpendicularly into contact with the lid wiper, until it bent slightly. All measurements were carried out at the central region of the lidwipers on the upper and lower lid

9. Study design Analytic cross section study two independent random samples Level of significance α= 0.05 H 0 is rejected if p ≤ α Statistical analysis with Mann- Whitney test (data not normally distributed)

10. Results

11. Sensitivity threshold upper eyelid

12. Results Sensitivity threshold lower eyelid

13. Results Mann Whitney Test LWU (g/mm 2 )LWL (g/mm 2 ) P-Worth (2- seitig)0.0300.002

14. Conclusion The results of this study suggest that lid margin sensitivity decreases with age No statistically significant difference could be found between the level of sensitivity on the lower and the upper lid

15. Thank you for your attention