Surgical enlargement of the nasomaxillary aperture and transnasal conchotomy of the ventral conchal sinus: Two surgical techniques to improve sinus drainage in horses.

ABSTRACT

OBJECTIVE: To evaluate 2 surgical techniques for establishing and/or improving paranasal sinus drainage in cadaver heads and horses with sinusitis and evaluate the feasibility of postoperative transnasal sinus endoscopy. STUDY DESIGN: Ex vivo study (equine cadaver heads) and case series. SAMPLE POPULATION Nine adult equine cadaver heads and 8 horses with recurrent sinusitis. METHODS: For the ex vivo study, the following procedures were performed on 9 cadaver heads preoperative and postoperative computed tomography (heads 1-6), endoscopy-guided transnasal conchotomy of the ventral conchal sinus (TCVCS) and surgical enlargement of the nasomaxillary aperture (SENMAP) on opposite sides (heads 1-3), combined TCVCS and SENMAP on both sides (heads 4-9), evaluation of sinus drainage before and after surgery (heads 7-9), and postoperative transnasal endoscopy (heads 4-9). For the case series, 8 horses with secondary sinusitis were treated in standing position with SENMAP and/or TCVCS and postoperative transnasal endoscopy. RESULTS: Sinonasal communications were successfully created in all cadavers and affected live horses. Transnasal endoscopy of all sinuses except the middle conchal sinus was possible in heads 4-9 and in all clinical cases. Sinus drainage was improved (P = .028) by combining techniques. Blood loss in live horses ranged from 0.5-5.5 L (1.95 ± 1.5) per horse. Sinusitis resolved in all affected horses during follow-up of 3.2-25.5 months (13.5 ± 8.5). CONCLUSION: Transnasal conchotomy of the ventral conchal sinus and SENMAP consistently created large sinonasal communications, facilitating sinus endoscopy and improving sinus drainage. CLINICAL SIGNIFICANCE: Transnasal conchotomy of the ventral conchal sinus and SENMAP are viable options to treat horses with sinusitis and anatomical obstructions of the sinonasal communications.