Standing thyroidectomy in 10 horses.

OBJECTIVE: To describe a surgical technique for thyroidectomy in horses with thyroid neoplasia under standing sedation and local anesthesia.

STUDY DESIGN: Retrospective study.

ANIMALS: Client-owned horses (n = 10).

METHODS: Medical records of horses with a history of thyroid enlargement were included in the study if thyroid gland enlargement was treated surgically via hemi- or bilateral thyroidectomy, with the horse standing and sedated. Data derived from follow-up clinical examination, performance level, recurrence, and cosmetic outcome were evaluated.

RESULTS: Thyroid enlargement was unilateral in 8 and bilateral in 2 horses. Histopathological findings included adenomas (5/10), adenocarcinomas (2/10), cystic hyperplasia (2/10), and C-cell adenoma (1/10). No major complications were encountered during or after surgery. All horses resumed their previous level of exercise within 6 weeks. Recurrence was diagnosed in 1 horse, 7 months after excision, and a second surgery was required. Recurrent laryngeal nerve neuropathy and seroma formation subsequent to surgery were not recorded in any of the cases.

CONCLUSION: Thyroidectomy can safely be performed with the horse standing and sedated with local anesthesia.

CLINICAL RELEVANCE: Performing standing thyroidectomy does not increase intraoperative or postoperative complications and could be considered for horses with thyroid enlargement amenable to surgery.