An 8-year-old spayed female mixed-breed dog was presented for an acute onset of bleeding around the left eye. Mild exophthalmos and massive subconjunctival hemorrhage on the globe and nictitating membrane were present in the left eye. Retrobulbar hemorrhage was suspected, and pain was implied on opening of the mouth because the patient resisted and vocalized. No other abnormalities were found on ophthalmic or physical examination. Further questioning of the owner confirmed potential brodifacoum ingestion, and prothrombin time and partial thromboplastin time were both markedly elevated. Treatment with oral vitamin K1 was implemented, and the subconjunctival hemorrhage was significantly improved within a few days of instituting treatment. All clinical signs of coagulopathy were completely resolved within 4 weeks of presentation. Coagulopathy secondary to brodifacoum ingestion can manifest as severe unilateral bulbar and nictitating membrane subconjunctival hemorrhage and exophthalmos due to retrobulbar hemorrhage without other clinical signs. 1. Introduction Intraocular and periocular bleeding can occur with primary disease of the globe and adnexa or as manifestations of systemic disease. Clinical signs are hyphema and hemorrhage of nearly any aspect of the eye, including the uvea, vitreous, retina, subretinal space, conjunctiva, subconjunctival, and retrobulbar space. Periocular and intraocular hemorrhages are most commonly associated with uveitis or retinal detachment [1] caused by infectious diseases, including systemic fungal [2] and rickettsial diseases [3–5]; immune-mediated diseases such as uveodermatologic syndrome [6]; bleeding and vascular disorders such as hypertension [7, 8], thrombocytopenia [9, 10], anemia [11] and coagulopathy [1]; neoplasia [1, 12]; diabetes mellitus [13]; and hyperviscosity syndrome from multiple myeloma [8, 14] and polycythemia vera [8]. Additionally, persistent hyperplastic primary vitreous [15], retinal dysplasia, preiridal fibrovascular membrane formation [16], and blunt or penetrating trauma [1, 17] can also cause intraocular hemorrhage. Retrobulbar hemorrhage occurs because of trauma or coagulopathy and can cause exophthalmos [18–21]. Conjunctival or scleral hemorrhage in dogs usually occurs focally as petechiae from a primary hemostatic disorder, which is typically due to thrombocytopenia. Although subconjunctival hemorrhage is uncommon, it can occur secondary to coagulopathy, trauma, and vasculitis [21]. It has also been reported to occur with Rocky Mountain spotted fever [3] and scleral rupture [17]. The aim of
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