ULTRASONOGRAPHIC EXAMINATION OF CERVICAL MASSES IN THE DOG AND CAT

The ultrasonographic appearance of clinically undifferentiated neck ma sses for which a definitive diagnosis was eventually obtained in ninet een dogs and one cat is presented in this report. Multiple lesions wer e seen ultrasonographically in 4 dogs and no cervical abnormalities we re seen in 2 dogs resulting in 22 lesions in 20 animals. Of 7 benign l esions, there were 2 patients with reactive lymph nodes from a regiona l inflammatory process, and 1 patient each with primary pyogranulomato us lymphadenitis, arteriovenous malformation, foreign body granuloma, cellulitis, and hematoma. Of 15 malignant lesions, 7 were thyroid carc inomas, 3 were lymphomas with submandibular and cervical lymph node en largement, 3 were lymph node enlargements associated with regional met astasis of malignant tumors, one was a leiomyosarcoma and one was a ca rotid body tumor. One dog with a diffuse soft tissue swelling of the v entral cervical region had only slight asymmetry of the thyroid lobes on ultrasound examination and no abnormalities of the neck at post mor tem. A second dog examined with ultrasound 4 months after surgical rem oval of a carotid body tumor had no evidence of tumor recurrence. Ultr asonographic examination provided information regarding the character of the lesions, the tissue or organ of origin, and invasion into other anatomic structures. Ultrasound examination in conjunction with fine needle or tissue biopsy provided a definitive diagnosis in those anima ls in which biopsies were performed.