Ethmoid Hematoma

This is a benign tumor, or mass of tissue, that originates from the highly vascular tissue of the ethmoid turbinates, subsequently expanding into the nasal passage, the paranasal sinuses, or both. Theethmoid turbinates are located partially in the sinus and partially in the nasal passages. The most common clinical sign is blood-tinged nasal discharge from one or both nostrils, but they can become large enough to result in partial obstruction of the nasal passage and subsequent respiratory noise. These signs can be seen when the horse is at rest or when exercising.

In horses with small tumors, the tumor is injected with formalin via an endoscope under standing sedation and allowed to necrose. It is important to note that these masses typically require multiple injections and recheck endoscopy procedures to get them to resolve. In cases with larger tumors, a sinus flap may be needed to remove the mass. A sinus flap involves opening a flap of bone into the sinus to allow exposure of the tumor for removal, usually with the horse under general anesthesia. Following surgery, the horse’s face typically heals with minimal cosmetic defects.