Unilateral thyroidectomy in 6 horses.
OBJECTIVE
To describe the surgical technique, complications, and outcome of thyroidectomy in 6 horses.


METHODS
Retrospective study.


METHODS
Six horses, 10 to 22 years of age, with unilateral, rapidly enlarging thyroid masses.


METHODS
Medical records between 1985 and 2000 were reviewed for horses that had unilateral thyroidectomy. Retrieved data included signalment, physical, clinical, and ultrasonographic examination findings, surgical technique, complications, and outcome. A minimum of 6 months follow-up was obtained.


RESULTS
Six horses were identified. Three horses had tracheal compression and 2 of these also had exercise intolerance. On ultrasonography (5 horses), the enlarged thyroid ranged from 125 to 990 cm(3), and had either a heterogeneous (1 horse), cystic (2), or homogeneous (2) appearance. En bloc, unilateral thyroidectomy under general anesthesia was performed in all horses. After surgery, 3 horses had ipsilateral laryngeal hemiplegia, but tracheal compression was resolved. Thyroid masses were adenoma (3), C-cell compact carcinoma (1), and adenocarcinoma (1). No tumor recurrence or metastatic disease was reported 6 to 14 months after surgery.


CONCLUSIONS
Unilateral thyroidectomy can be successfully performed in horses with large thyroid tumors, but laryngeal hemiplegia can be an important surgical complication. Ultrasonographic examination is useful to define thyroid enlargement and location but is seemingly not useful to characterize tumor type.


CONCLUSIONS
Thyroidectomy is an uncommon surgical procedure and has an attendant risk for recurrent laryngeal nerve damage. Laryngoscopic examination before and after surgery and careful isolation of the recurrent laryngeal nerve during surgery is recommended.
Elce
Yvonne A
YA
Department of Clinical Studies, New Bolton Center, University of Pennsylvania, Kennett Square, 19348, USA.
Ross
Michael W
MW
Davidson
Elizabeth J
EJ
Tulleners
Eric P
EP
D000230:Adenocarcinoma / Q000453:epidemiology / Q000601:surgery / Q000662:veterinary; D000236:Adenoma / Q000453:epidemiology / Q000601:surgery / Q000662:veterinary; D000818:Animals; D018276:Carcinoma, Medullary / Q000453:epidemiology / Q000601:surgery / Q000662:veterinary; D003560:Cysts / Q000453:epidemiology / Q000601:surgery / Q000662:veterinary; D005260:Female; D006734:Horse Diseases / Q000000981:diagnostic imaging / Q000453:epidemiology* / Q000473:pathology / Q000601:surgery*; D006736:Horses; D008297:Male; D010414:Pennsylvania / Q000453:epidemiology; D011183:Postoperative Complications / Q000662:veterinary; D011996:Records / Q000662:veterinary; D012189:Retrospective Studies; D013959:Thyroid Diseases / Q000453:epidemiology / Q000601:surgery / Q000662:veterinary*; D013964:Thyroid Neoplasms / Q000453:epidemiology / Q000601:surgery / Q000662:veterinary; D013965:Thyroidectomy / Q000706:statistics & numerical data / Q000662:veterinary; D014463:Ultrasonography