Surgical management of an ethmoid cyst in a horse.

The research presents the case of a 2-year old racehorse that underwent surgery for the removal of an ethmoid cyst, identified due to a persistent nasal discharge. Post-surgery, the horse no longer suffered from the nasal discharge, indicating the operation’s success.

Case Overview

• The case study focuses on a Thoroughbred filly or juvenile female horse with a persistent nasal discharge. This symptom, persistent for one month, prompted further examination, leading to the diagnostic of an ethmoid cyst.

Diagnosis Process

• Contrast radiography, a type of medical imaging procedure that highlights specific areas inside the body, was performed. This revealed a circumscribed mass located in the right maxillary sinus, extending to the frontal sinus and ethmoid labyrinth. The ethmoid labyrinth is a complex structure in the skull involved in smell and air filtration.
• A discrete attachment of the mass to the ethmoid labyrinth was identified, further indicating that the mass, or cyst, originated from the ethmoid labyrinth.

Surgical Treatment and Examination

• The cyst was surgically removed, which effectively eliminated the horse’s nasal discharge, a symptom of the ethmoid cyst.
• The external structure of the mass resembled a turbinate, part of the nasal structure, with a thin bony wall covered by a smooth mucosal membrane. The internal structure featured a lining membrane containing multiple fluid-filled cystic structures, ranging from 1-3 cm diameter.

Histological Analysis and Conclusions

• Further histological analysis of the cyst revealed that its multi-cavitated structure was similar to the ethmoid labyrinth confirming the origin of the cyst.
• The connection of the cyst to a single site on the ethmoid labyrinth and its similarity in structure further validated the belief that the cyst was ethmoid in origin. Thus, the surgical operation was successful in treating the ethmoid cyst and eliminating the associated nasal discharge.