Surgeon's Corner: Parathyroidectomy in a Dog
Howard B. Seim, DVM, DACVS, Colorado State University
Presentation
Two patients presented and underwent extensive diagnostic workup for persistent hypercalcemia; the likely diagnosis for each was a parathyroid adenoma or other parathyroid mass.
Surgery
The approach is very similar to feline thyroidectomy. The patient is placed in dorsal recumbency and a midline cervical incision is made to expose the trachea. Self-retaining Gelpi retractors are used to maintain visualization of the cervical region. The thyroid gland is isolated and its surface is carefully evaluated to determine if there are any areas in the cranial or caudal pole that seem unusually large. In the first patient, a mass is identified at the cranial pole of the right thyroid gland, which appears to be originating in the parathyroid gland. Bipolar cautery is used to separate the parathyroid from the capsule of the thyroid, and the parathyroid mass is removed, ensuring that all parathyroid tissue is included in the resection. Care is taken to ensure that no other masses are apparent.
The second patient undergoes a similar dissection as was seen in the previous patient (note the patient’s head is oriented toward the bottom of the screen). The trachea is exposed and the thyroid glands are both visualized and carefully inspected. A bulge seen in the caudal aspect of the thyroid gland is most likely the parathyroid mass causing this patient’s hypercalcemia. In this particular case, the surgeon elected to remove both the parathyroid and thyroid glands because the tumor was buried within the central portion of the thyroid tissue, and careful dissection likely would not be successful in removing all of the parathyroid tissue. Once the cranial thyroid artery is identified, bipolar cautery is used for hemostasis. On inspection of the opposite side, the cranial pole of the thyroid gland was felt to be possibly enlarged as well. The surgeon elected to biopsy the area to determine if the parathyroid gland was adenomatous or normal tissue. In this case, the tissue was confirmed to be normal parathyroid tissue.
Closure is routine, closing the sternohyoideus-thyroideus muscles, the subcutaneous tissue, and then the skin.
Outcome
Once removed, the thyroid and parathyroid gland were incised to reveal a cystic mass that was histologically confirmed to be a parathyroid adenoma.
This video was authored by Howard B. Seim III, DVM, DACVS. Other surgical videos are available through VideoVet.
Surgeon’s Corner is intended as a forum for those with specialized expertise to share their approaches to various techniques and procedures. As such, the content reflects one expert’s approach and is not subject to peer review.