(A) Topical anesthesia is placed in each eye. Whatman 41 filter strips are placed in the temporal inferior cul-de-sac. (B) The filter strip absorbs the tears as they are produced.
Adapted with permission from: Paysse EA, Coats DK, Cassidy M. Refinements Volume III/Number 2. San Francisco: American Academy of Opthalmology, 1999.