Surgery
Surgery is an option after failure of appropriate medical therapy113,165. Modern endoscopic sinus surgery (ESS)
relieves sinus outflow obstruction, debrides inflamed tissue and
provides improved access for topical agents 166.
Relief of obstruction is more relevant in mild to moderate CRSsNP4 and balloon dilation may be sufficient in selected
cases 167. Mucus stasis from obstruction promotes
microbial overgrowth and infectious inflammation predominantly in
non-polypoid T1,3 inflammation. Relieving obstruction is of less value
in CRS cases with diffuse inflammation as in CRSwNP and severe CRSsNP,
in particular when associated with T2 inflammation168,169. Although high-level data is lacking, more
extensive surgical procedures such as a ‘full house ESS’ are typically
recommended for these cases 170-172. Maximum surgical
approaches are reserved for the most severe cases and involve removal of
the floor of the frontal sinus and in some cases sinus mucosa173-176. Surgical recurrence rates are generally
correlated with the intensity of T2 tissue inflammation177-181. Systemic markers of T2 inflammation such as
blood eosinophilia are associated with surgical failure even in the
absence of a T2 signature in the tissue 182. In
non-eosinophilic CRS, limited available data suggests that higher
intensity of T1 and T3 inflammation also favors surgical failure182,183.