Intraoperative depression of the bulla of the maxillary septum as a method of improving sinus drainage without epistaxis in horses

Summary Current methods of creating sinus drainage and allowing egress of a sinus pack at the end of surgery create significant haemorrhage. Given that haemorrhage is already a concern in some sinus surgeries, the method described allows for a significant reduction in blood loss. The objective was to describe a method of enlarging the nasomaxillary aperture in horses to allow egress of a sinus pack, and subsequent endonasal treatment, without incurring significant haemorrhage. The bulla of the maxillary septum is depressed using a gloved finger (through a sinus flap or trephine hole) or using a long curved Peine instrument under sinoscopic control before fenestration. No major operative or post‐operative complications have been encountered. Satisfactory widening of the nasomaxillary aperture has been accomplished in all cases, although at times, when the bulla is under the floor of the dorsal conchal sinus, it can be difficult to compress. It is imperative that this procedure be performed before fenestration. If performed after fenestration, the most rostral edge of the fenestration can be difficult to identify, and this becomes an impediment to widening the nasomaxillary aperture. Enlarging the nasomaxillary aperture with a finger or blunt instrument allows improvements in sinus drainage without the complication of severe epistaxis. Depression of the bulla of the maxillary septum, before surgical fenestration into the rostral maxillary and ventral conchal sinuses, allows opening of the nasomaxillary aperture with minimal haemorrhage. Thereafter, the sinus pack can be egressed via this route, which is also large enough to perform sinus lavage and post‐operative treatments endonasally without the risk of disturbing the external surgical site.