The cysts are lined with epithelium, and usually occur in the ventral conchae or maxillary sinuses,[1] most commonly in horses less than one year old.
[3] Sometimes, a mucoid nasal discharge occurs, which is caused by obstruction to mucociliary clearance,[3] and therefore does not resolve following antibiotic treatment.
[4] If the cyst is located in the caudal maxillary sinus, it may cause the eyeball on the affected side to bulge out of the orbit, known as exophthalmos.
[5] Radiographs generally provide better results than endoscopic examination when diagnosing these problems; multiloculated densities and fluid lines show up more readily in the sinuses, occasionally with dental displacement and also dental and jaw line distortion, flattened roots in the teeth, mineralization and soft tissue calcification, and major deviation of the septum and vomer bones.
[citation needed] Cysts are removed by surgery, which may be performed with the horse standing and sedated, or under general anesthesia.