Equine nasal cysts are abnormal fluid filled sacs which occur inside the nasal sinuses of horses. 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.[2] Surgical removal of the cyst has a good prognosis for the horse.

Characteristics edit

The most common sign of a nasal cyst is facial swelling, with obstruction of the nasal passage.[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]

Diagnosis edit

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]

Treatment edit

Cysts are removed by surgery, which may be performed with the horse standing and sedated, or under general anesthesia.[3] Treatment involves surgical removal of the cyst and any of the involved lining of the concha.

Prognosis edit

The prognosis for a complete recovery is good, and the rate of any recurrence is minimal.[5] Some horses may have a mild mucous discharge after surgery, which can be permanent.[1]

Epidemiology edit

Most nasal cysts are identified in horses younger than one year old, but can also be diagnosed in horses over 9 years of age.[1] There is no known breed or sex predisposition for nasal cysts.[4]

See also edit

Ethmoid hematoma

References edit

  1. ^ a b c Rush, Bonnie R. (2019). "Sinus cysts". The Merck Veterinary Manual. Retrieved 2019-10-26.
  2. ^ Rush, Bonnie; Mair, Tim (2008). "Paranasal sinus cysts". Equine Respiratory Diseases. Blackwell Science. pp. 48–49. ISBN 9781405155311.
  3. ^ a b c Lane, J. Geoffrey (23 January 2013). "Disorders of the ear, nose and throat". In Mair, Tim; Love, Sandy; Schumacher, James; Smith, Roger K.W.; Frazer, Grant (eds.). Equine medicine, surgery and reproduction (2nd ed.). Elsevier. p. 89. ISBN 9780702052026.
  4. ^ a b Wilson, David (2010). "Sinonasal cysts". Clinical veterinary advisor. The horse. Elsevier Saunders. p. 527. ISBN 9781437714494.
  5. ^ a b Dwyer, Ann E. (2016). "Practical field ophthalmology". In Gilger, Brian C. (ed.). Equine Ophthalmology (3rd ed.). John Wiley & Sons. p. 175. ISBN 9781119047858.