Potential risk factors associated with the development of synechiae following functional endoscopic sinus surgery

Synechiae formation in the middle meatus is the most common complication of functional endoscopic sinus surgery (FESS). Our objectives were to determine the incidence of synechiae occurring in a cohort of patients that have undergone FESS and identify characteristics associated with the development of synechiae postoperatively.

A retrospective chart review was conducted of CRS patients, with or without nasal polyposis, that had undergone bilateral FESS in the past. All patients had received non-absorbable spacers intraoperatively that were left in situ for 6 days. Demographic and preoperative variables were analyzed to identify synechiae risk factors. A multivariable logistic regression model was constructed to estimate the probability of developing synechiae, given demographic and preoperative variables.

Two hundred cases of bilateral FESS were retrospectively reviewed. Thirty-eight (19.0%, 95% CI 13.6-24.4%) patients developed synechiae. Individuals receiving primary FESS and nasal septal reconstruction (NSR) were strongly associated with the development of synechiae (OR 3.5, 95% CI 1.5-8.5; OR 3.0, 95% CI 1.3-6.9). A multivariable logistic regression model adjusting for NSR, recurrent FESS, concha bullosa, requirement of anterior and posterior ethmoidectomy, Lund-Mackay CT score and gender, identified the likelihood of developing synechiae with a sensitivity of 68%, specificity of 73%, positive predictive value of 38% and likelihood ratio of 2.5.

Patients undergoing primary FESS and NSR are at greatest odds of developing postoperative synechiae. Methods of assessing risk factors and preventing synechiae formation in this population should be evaluated in future prospective investigations.