Outcome measurements
The primary outcome was the mean difference in the fluorescein staining
score under a
blue-light filter system in all interesting areas between the two
groups. The distribution of fluorescein at each interesting area was
graded from the video record independently by two blinded assessors. The
degree of fluorescein stain was graded according to a study by Harvey
RJ. et al.(9) which grade 0 was defined as no staining of
fluorescein on the sinus cavity, grade 1 was partial staining of
fluorescein (present on one wall of the sinus cavity), grade 2 was
staining of fluorescein on two or more walls of the sinus cavity, and
grade 3 was pooling of fluorescein in the sinus cavity.(Figure
1)
The secondary outcomes included the mean differences in the staining
score of
fluorescein under a blue-light filter system in each area and subgroup
analysis according to the phenotype features, CRSwNP and CRSsNP, and the
severity of the disease by the LM staging system.