COMPUTED-TOMOGRAPHY - DIRECTED FINE-NEEDLE ASPIRATION OF SKULL BASE PARAPHARYNGEAL AND INFRATEMPORAL FOSSA MASSES

Suspicious findings in the parapharyngeal region on computed tomograph ic (CT) or magnetic resonance imaging studies can be a diagnostic prob lem. Blind biopsy through the mucosa can be inadequate, since the abno rmality is not directly visible. With CT guidance, fine needle aspirat ion (FNA) of parapharyngeal masses can be performed with a needle conf idently placed within the lesion. Vital structures such as the carotid artery are avoided. We present a series of 33 CT-guided FNA on 30 pat ients to evaluate the safety and the degree of accuracy of the procedu re. Most of the patients had been treated previously for local maligna ncy. All patients had surgical pathologic study, autopsy, or clinical and imaging follow-up to confirm the FNA cytology results. Twenty of t he 33 biopsies were positive for malignant cells, confirming recurrenc e of the primary head and neck malignancy. Of the 33 CT-directed FNA, 13 were negative for malignant cells. Three of these 13 were found to be false-negative FNA. None of the patients had complications from the procedure. CT directed FNA of masses at the skull base or in the para pharyngeal area can be performed safely. A high degree of accuracy is achieved, with 30 (90.9%) accurate in identifying the presence or abse nce of malignancy in our series.