The effect of expandable polyvinyl acetate packing for preventing stenosis of the frontal sinus ostium.

The aim of this study was to evaluate the effect of repeated expandable polyvinyl acetate (EPA) packing for preventing stenosis of the frontal sinus ostium after patients undergo functional endoscopic sinus surgery (FESS). A nonrandomized, prospective study of 20 patients with chronic frontal sinusitis was conducted based on the Lund-Mackay scoring system. EPA was packed, for 3 days/week, in total, three times for 3 weeks, into the left frontal sinus ostium right after FESS. For the control, the right side frontal sinus ostium was left unpacked. After 6 months, the patency of the frontal sinus ostium was measured with a ruler under endoscopic guidance and the patency was classified as obstructed, stenotic, or patent according to the size. Obstruction developed in the right side in four patients and in the left side in two patients. Stenosis was found in the right side in eight patients and in the left side in one patient. The ostium of the frontal sinus was patent in the right side in 8 patients and patent in the left side in 17 patients. The sizes of the ostia were significantly different between the frontal sinuses on both sides 6 months after FESS (p < 0.05). The outcome of repeated EPA packing was favorable in patients undergoing FESS.