Exophthalmus secondary to a sinonasal cyst in a horse.

The study presents the case of a 13-year-old female Miniature Horse suffering from a progressive eye disorder, called unilateral exophthalmia, which was traced back to a sinonasal cyst. Elimination of the cyst through surgical means led to the resolution of the eye disorder, and no recurrence happened within four months following surgery.

Objective of the Research

• This research is a case study discussing the diagnosis, treatment, and consequence of a sinonasal cyst in a 13-year-old female Miniature Horse. The cyst was responsible for causing unilateral exophthalmia, a condition causing one eye propound from the socket.

Methodology of the Study

• The horse was subjected to a physical examination, which came out unremarkable.
• An ophthalmic examination followed, and it was discovered that the horse was resistant to retropulsion in the left eye, indicative of exophthalmia, along with mild blepharoconjunctivitis.
• A computed tomography (CT) scan was performed, revealing a massive substance in the left behind part of maxillary and conchofrontal sinuses.
• The substance extended to the retrobulbar space of the left side and was in contact with the cribriform plate.
• Trephination was performed which released dense yellow fluid. This confirmed the existence of a sinonasal cyst.

Treatment

• The treatment involved a surgical procedure known as frontonasal osteoplastic flap. This operation excised the cyst mostly, leading to complete elimination of the exophthalmia.

Results

• The result from the surgery confirmed the diagnosis of the cyst. The recovery was successful with no signs of either the cyst recurrence or the eye disorder within four months post-surgery.

Conclusion

• The research concludes that a sinonasal cyst should be considered a possible differential diagnosis for any horse with retrobulbar disease. In case exophthalmia is the only symptom , there is a high probability it could be caused by a sinonasal cyst.