2016 Section 5 Green Book

Fig. 3. Mast cells stained with CD117.

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.

(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

Fig. 4. Microscopic hematoxylin and eosin slide (2 3 ) of a nasal polyp demonstrating stromal distribution of cells within the circle.

Han: Subclassification of Chronic Sinusitis

Laryngoscope 123: March 2013

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