Dentigerous cysts with exostosis of the temporal bone in horses – A new variant diagnosed by computed tomography

Equine Vet Educ. May 2022;34(5):e181-e186. 18 Refs

F Heun¹, A Schwieder, F Hansmann, A Bienert-Zeit, M Hellige²

¹ Clinic for Horses, University of Veterinary Medicine Hannover, Foundation, Hannover, Germany.; ² maren.hellige@tiho-hannover.de

Author Abstract

The dentigerous cyst or temporal teratoma in horses is a well-known congenital malformation that occurs in the temporal region and usually contains dental tissue. This case report describes two horses with a previously unreported variant of the dentigerous cyst associated with an exostosis arising from the temporal bone. The principal clinical sign was a draining tract opening at the margin of the right pinna in both horses. There was no evidence of an ectopic tooth on the radiographs or at ultrasonographic examination. Computed tomography combined with positive contrast sinography of the draining tract revealed bone formation arising from the supramastoid crest of the right temporal bone extending towards a cyst-like structure but without direct connection in both cases. This bone formation was located at a site on the supramastoid crest, close to the external acoustic meatus, where ectopic teeth may also occur. Both cysts were removed surgically with a good long-term outcome.

Keywords

horse, temporal teratoma, dermoid cyst, temporal odontoma, heterotopic polyodontia

Article Tools:

Email to me

Archives Highlights:

Challenges and Outlook of Veterinary Education in Iran: A Survey of Veterinary Students at Urmia University During the COVID-19 Pandemic.
Regarding future employment, 45.8% of participants wanted to start their own business or practice, whereas 54.2% preferred employment opportunities. A significant 81.6% of participants said they would consider emigrating to pursue better career prospects.

Factors Associated with Medication Noncompliance in Dogs in New Zealand.
Medication noncompliance was recorded for 47% (71/151) of owners. Increasing dog age was associated with better owner compliance. Forty-seven percent (71/151) of owners reported that "nobody" showed them how to administer the medication. One-third of dog owners (47/151) reported challenges in medicating their pets. The most common reason cited by clients reporting challenges was a resistant pet.

Resolution of egg binding is possible in most client-owned parrots when multiple treatment strategies are considered.
Of the 150 events that had complete follow-up, 109 (72.7%) resulted in a successful outcome. A successful outcome was observed in 44 of 133 events (33.1%) that were initially managed medically without resorting to additional treatment strategies, in 31 events (86.1%) managed with mechanical assistance, in 20 events (60.6%) managed surgically, and in 12 events (85.7%) managed with ovocentesis.

Indications for Radiation Therapy in Veterinary Medicine
This article highlights some of the essential elements for clinical decision making in veterinary radiation oncology, with case examples to give general practitioners a better understanding of what types of cases may be appropriate for radiation therapy.

Recovery of ambulation in small, nonbrachycephalic dogs after conservative management of acute thoracolumbar disk extrusion.
Forty-nine of fifty-one (96%) of deep pain-positive and 10/21 (48%) of deep pain-negative dogs recovered ambulation within the 12-week period. The median time to ambulation was 11 and 25 days for deep pain-positive and -negative dogs, respectively. Reduction in spinal cord compression varied among individuals from minimal to complete and apparently was unrelated to the recovery of ambulation.