2016 Section 5 Green Book

(SAS Institute Inc., Cary, NC), the nonparametric Wilcoxon

ranked sum test was employed to assess significance of findings

for all analyses between CRS subclasses. Spearman coefficient

of rank correlation test was utilized to calculate correlations

between the measurement tools for each subclass of CRS and

control group.

Histopathology and Immunostaining

Informed consent was obtained prior to obtaining the

nasal polyps in patients who failed medical treatment for CRS

and were undergoing ESS. The nasal polyps specimens for the

study groups were taken specifically from the ethmoid sinuses

or polyps in the ostiomeatal complex. For the control group, eth-

moid sinus mucosa was taken during the CSF leak repair. All of

the patients did not receive oral steroid 4 weeks prior to the

specimen collection. Tissue samples were then evaluated for eo-

sinophils (EO),

polymorphonuclear leukocytes (PMN),

lymphocytes, and plasma cells with hematoxylin and eosin

(H&E) staining. Degree of fibrosis was measured using Masson

trichrome staining (Fig. 2). Mast cells were identified with

CD117 immunostaining (Fig. 3).

For the H&E staining, nasal polyps were evaluated for the

area with the most dense cell populations similar to standard

clinical evaluation of any pathologic tissue. This location of the

dense collection of inflammatory cells was determined as either

Fig. 2. Degree of fibrosis was graded on level of trichrome stain-

ing. (A, B, C) Representative scores 0, 1, and 2, respectively.

Fig. 3. Mast cells stained with CD117.

Fig. 4. Microscopic hematoxylin and eosin slide (2

) of a nasal

polyp demonstrating stromal distribution of cells within the circle.

Laryngoscope 123: March 2013

Han:

Subclassification

of Chronic

Sinusitis