Sinus Irrigation Penetration After Proposed Modified Draf IIa Technique in a Side-to-Side Cadaveric Model

Abstract

Background Endoscopic sinus surgery (ESS) is an effective intervention for patients with medically refractory chronic rhinosinusitis. Frontal sinusotomy is the most challenging part of ESS, with one of the key outcomes being access for topical irrigations. Objective The purpose of this study is to compare irrigation penetration into the frontal sinus following Draf IIa versus modified Draf IIa frontal sinusotomy. Methods Four fresh cadaver heads were used in this experiment. Draf IIa was performed on one side of each head and a modified Draf IIa on the contralateral side. This proposed modification consists of a Draf IIa combined with an agger nasi punch-out procedure and partial trimming of the vertical lamella of the middle turbinate back to the posterior table of the frontal sinus without drilling the beak. Each head was irrigated with methylene blue-dyed water and recorded by rigid endoscopy through an endonasal view (EV) of the frontal sinus and frontal trephination view (TV). Two blinded rhinologists scored the extent of staining (using an ordinal scale of 0 to 3) for each side. A case report where the modified Draf IIa was performed is also described. Results After modified Draf IIa sinuosotomy, the mean score for the EV was 2.125 and for the TV was 2, versus 0.875 and 0.625 for traditional Draf IIa, respectively. There was a statistically significant increase for both EV (p = 0.019) and TV (p = 0.018) after modified Draf IIa. Conclusion In our cadaveric model, this procedural modification improved penetration of postoperative irrigations into the frontal sinus. This simple technique may be easily adapted into frontal ESS when indicated.