Ultrasound examination of the head and neck

Abstract

Structure of this thesis Part I deals with basic bio-physics and bio-effects of clinical ultrasound of the head and neck. Furthermore, the ultrasound anatomy of the head and neck is described and illustrated. In addition, the technique of ultrasound guided fine needle aspiration biopsy (UGFNAB) is outlined. In part H the significThe fallibility of palpation and current diagnostic tests to detect subclinical (occult) nodal disease in patients with upper aero-digestive tract cancer results in imperfect staging, improper treatment and delayed identification of recurrences in the neck. With continuous advances in imaging techniques (CT, MRI), the sensitivity for the detection of cervical lymph nodes is true enough increasing, while the specificity for detecting metastasis with these techniques remains low. An ideal diagnostic test should be suitable for screening, demonstrating and excluding cervical metastasis. In addition, the test should have no morbidity. The diagnostic work-up of patients with a head and neck mass is another important diagnostic problem. Although careful history taking and thorough ENT examination may be sufficiently characteristic to permit diagnosis, every clinical diagnosis will be associated with a certain degree of uncertainty. This uncertainty is mainly deterntined by the lintitations of clinical exantination in differentiating between solid and cystic lesions on one hand, and the establishment of exact anatontic properties on the other. In addition, there is a proportion of lesions which, despite thorough diagnostic work-up. remain elusive and are subjected to premature surgical exploration. CT may contribute to the pre-treatment work-up but is associated with several important drawbacks: high costs, lintited availability, radiation exposure and the need to use intravenous contrast. A simple, uniformly reliable, non-invasive and cost-effective test would be beneficial in these cases. The low accuracy of current diagnostic methods in the assessment of cervical nodal disease and the difficulties to evaluate head and neck masses actuated the present study, which started in 1984. By that time small-parts ultrasound transducers had been developed. These high-frequency transducers seemed better suited for examination of the superficial tissues in the head and neck region than earlier ultrasound equipment. In close cooperation between the departments of Radiology and Otorhinolaryngology and Head and Neck Surgery. a prospective study on the value of ultrasound examination of the head and neck was designed. The purpose of this study was to deterntine the values of palpation and ultrasound examination in the assessment of cervical metastatic disease in patients with upper aerodigestive tract cancer and in the evaluation of head and neck masses. An additional purpose of this study was to appraise the adjunctive value of cytologic exantination in the above mentioned clinical problem