Evaluation of tear fluid production using Schirmers' tests is a well-known and frequently used examination method in ophthalmology. Schirmers' test objectively indicates the tear fluid production over five minutes by insertion of a filter paper strip in the lower conjunctival fornix. Commonly, this method is used to quantify tear fluid production, but not tear fluid composition. The development of novel, very precise analytical methods opens up new possibilities in the use and application of Schirmers' test strips. A recently introduced analytical method is mass spectrometry. This method allows the detection and quantification of proteins, lipids, and metabolites in very low amounts of samples. Whether systemically ingested agents such as omega-3 fatty acids or acetylsalicylic acid can be detected in tear fluid using this method remains unclear. The aim of this study is to investigate the detectability of 2 different agents (acetylsalicylic acid and omega-3 fatty acids) in Schirmers' test strips from healthy subjects after intake for 1 week by use of untargeted mass spectrometry. Participating healthy subjects will receive either acetylsalicylic acid or omega-3 fatty acids.
Study Type
INTERVENTIONAL
Allocation
RANDOMIZED
Purpose
DIAGNOSTIC
Masking
NONE
Enrollment
32
Dose: 1 tablet per day starting from visit 2 until visit 3, intake in the evening
Dose: 2 tablets per day starting from visit 2 until visit 3, intake in the evening
Medical University of Vienna, Department of Clinical Pharmacology
Vienna, Austria
Concentration of omega-3 fatty acids/ASS detectable in Schirmer's tear strips using mass spectrometry
Time frame: one week
Change of nAUC (normalised area under the curve) of tear fluid metabolics from baseline to follow-up visit using mass spectrometry
Time frame: one week
To evaluate the influence of omega-3 FA/ASS on lipid layer thickness
Lipid layer thickness will be measured by LipiView and expressed as nanometers
Time frame: one week
To evaluate the influence of omega-3 FA/ASS on corneal sensation
Corneal sensation as measured by a Cochet-Bonnet aesthesiometer will be expressed as milimeters
Time frame: one week
To evaluate the influence of omega-3 FA/ASS on tear film break up time
Tear film break up time will be measured clinically and expressed as seconds
Time frame: one week
To evaluate the influence of omega-3 FA/ASS on Schirmer-1 test
Schirmer-1 test will be expressed as milimetres/5 minutes
Time frame: one week
To evaluate the influence of omega-3 FA/ASS on choroidal perfusion
choroidal perfusion will be measured using a LSFG device and expressed as mean blur rate
Time frame: one week
To evaluate the influence of omega-3 FA/ASS on central macular thickness
central macular thickness will be measured by OCT and expressed as µm
Time frame: one week
To evaluate the influence of omega-3 FA/ASS on vessel density as assessed by optical coherence tomography angiography
vessel density will be measured by OCTA
Time frame: one week
To evaluate the influence of omega-3 FA/ASS on tear film osmolarity
tear film osmolarity will be measured by TearLab and expressed as mOsm/L
Time frame: one week
Concentration of omega-3 fatty acids/ASS detectable in finger sweat samples and blood samples using mass spectrometry
Time frame: one week
This platform is for informational purposes only and does not constitute medical advice. Always consult a qualified healthcare professional.