[DrafⅢ approach to unilateral frontal sinus for contralateral drainage].

<b>Objective:</b>Anatomical variation or scar atresia of the drainage channel of the frontal sinus on the affected side, and opening the frontal sinus through the drainage channel of the frontal sinus on the affected side may lead to surgical failure. The purpose of this study is to explore a modified Draf Ⅲ operation to complete the drainage of the affected frontal sinus by removing the floor wall and septum of the frontal sinus and connecting the bilateral frontal sinus through the healthy side of the frontal sinus. <b>Methods:</b>Through the anatomical study of 2 skull bone specimens and 2 fresh frozen specimens, the surgical landmark and surgical approach were explored. Four patients with frontal sinus atresia and frontal sinusitis after DrafⅡb surgery in Eye & ENT Hospital of Fudan University were retrospectively analyzed. Descriptive method was used to analyze the data. <b>Results:</b>The bottom wall of bilateral frontal sinus was removed, and the bilateral frontal sinus was enlarged above the nasal septum to form a large common cavity. The uncinate process and ethmoid bubble were retained, and the midline drainage of the affected frontal sinus in the healthy side of the nasal cavity was completed. From August 2022 to April 2023, 4 patients with frontal sinus atresia and frontal sinusitis after DrafⅡb surgery for unilateral frontal sinus papilloma in Eye & ENT Hospital of Fudan University were treated with surgery. The headache symptoms disappeared after surgery, and the drainage of frontal sinus was spacious, the mucosa healed well and the drainage was unobstructed under endoscopy. There were no other postoperative complications. <b>Conclusion:</b>DrafⅢ approach to unilateral frontal sinus for contralateral drainage can drain the affected frontal sinus adequately. The essence of this operation is to drain the bilateral frontal sinus in the unilateral nasal cavity, and this operation has short path, less trauma, and a broader prospect, which is suitable for promotion.