[An evaluation of histopathological changes in ethmoid sinus mucosa after endoscopic sinus surgery]

This study aims to evaluate postoperative histopathological changes in ethmoid sinus mucosa in patients undergoing limited or extensive endoscopic sinus surgery (ESS) due to chronic rhinosinusitis.

A total of 120 patients (74 males, 46 females; mean age 33 years; range 18 to 56 years) with chronic rhinosinusitis who underwent limited ESS (n=40), extensive ESS (n=40) and septoplasty or septorhinoplasty (n=40) in our clinic between May 2009 and October 2010 were enrolled. The control group consisted of patients who underwent septoplasty and septorhinoplasty alone. We took samples from the anterior ethmoid sinus mucosa at postoperative sixth months for the patients who underwent ESS and intraoperatively for the control patients. Tissue slices of mucosa samples were investigated under light microscope in terms of epithelial erosion, squamous metaplasia, submucosal fibrosis, basal membrane thickening, submucosal edema and submucosal inflammation. Histopathological findings of limited and extensive ESS groups were compared to each other and the control group.

The incidence of squamous metaplasia and submucosal fibrosis was significantly higher in extensive ESS group, compared to limited ESS group (p=0.003 and p<0.001, respectively). Both of ESS groups had significantly higher incidences of epithelial erosion, submucosal fibrosis, basal membrane thickening, submucosal edema, submucosal inflammation, compared to the control group (p<0.001).

Our study results show that ethmoid sinus mucosa may be still abnormal at the postoperative sixth month following ESS, regardless of the extension of ethmoidectomy. These patients should be followed closely, as they may have recurrent rhinosinusitis in the postoperative period due to impaired mucociliary activity.