Thyroid ultrasound scanning technique in dogs and cats

Objective: To demonstrate the ultrasound scanning technique of the thyroid gland in dogs and cats.

Animals: Dogs and cats undergoing thyroid ultrasonography.

Methods: Patients are typically positioned in dorsal recumbency; however, the examination can also be performed in other positions. A standing position may be particularly beneficial in cats by gently stabilizing the head with one hand while holding the probe in the other hand. The ventral cervical region is clipped, and alcohol is applied, followed by a coupling gel. A high-frequency linear probe is placed transversely over the trachea, caudal to the larynx. The probe is slowly moved caudally until the thyroid lobes are identified lateral to the trachea and medial to the carotid arteries. Each lobe is assessed in transverse and longitudinal planes. The parathyroid glands, when visible, are noted. Cine loops are recorded when necessary to assist in image review.

Results: The technique consistently allows identification and evaluation of the thyroid lobes in both dogs and cats. In most cases, examinations are successfully performed without sedation.

Clinical relevance: Ultrasonography provides a noninvasive and accessible method for evaluating the thyroid glands in dogs and cats. The mastery of proper scanning techniques facilitates the recognition of anatomical structures and pathological changes, enhancing both clinical and research applications. This method also provides a foundation for ultrasound-guided sampling procedures.