Progressive ethmoid hematoma was first described by Cook and Littlewort in 1974 in an analysis of 16 cases. it is a rare vascular lesion of the mucosa of the ethmoid turbinates that is unique to the horse. The reported incidence is 1 in every 2500 horses presented in referral hospitals. The pathogenesis of these lesions is still unknown. Treatment is recommended due to the progressive and potentially destructive nature of the lesion. Treatment methods include surgical ablation, intralesional formalin injection, laser ablation, and cryotherapy. Irrespective of treament method prognosis is guarded to poor for complete resolution of clinical signs due to high recurrence rates of 30-50%.