Quantitative tear ferning. Methodologic and experimental investigations.

  title={Quantitative tear ferning. Methodologic and experimental investigations.},
  author={Mogens S Norn},
  journal={Acta ophthalmologica},
  volume={66 2},
The reproducibility of different tear-ferning methods has been investigated by double tests on 122 subjects. Rough grading according to Rolando gives identical recovery in only 42 to 50%. Quantitative test (mm2 ferning per 1 microliter) of conjunctival fluid drawn with a glass rod according to Rolando gave a coefficient of variation of 99 to 128%. Aspiration with a quantitative pipette acc. to Norn 79%, and 55% for a standardized dilution (2.5 microliters of water) in the same pipette. The… CONTINUE READING