Collection of Human Tear Fluid Using Schirmer Strip

Begin by wearing gloves and sanitizing hands to prevent sample contamination. Check that the inner packaging of the Schirmer strip is sterile, unexpired, and intact. Next, bend the top of the Schirmer strip slightly inward at the zero millimeter mark near the semicircle tip.

Remove the strip by holding the end avoiding direct contact with the zero to 25 millimeter sample collection area. Instruct the subject to look away. Then gently pull down the lower eyelid.

Hook the strip end in the lower fornix near the lateral canthus region. After repeating the process for the other eye, ask the subject to close their eyelids gently to minimize irritation. Collect the tear fluid for approximately five minutes until a 15 to 20 millimeter tear sample is obtained.

Instruct the subject to open their eyes. Gently pull down the lower eyelid and remove the strips. Next, inspect the hydrated length on the strip and record the collected amount in millimeters.

Dry the strip using a standard clean frame heater until the fluid evaporates. Once dried, place the Schirmer strip into a labeled cryo tube and store it in a cool dark place for further processing.