One hundred eighty-four diagnostic aspirations performed on 169 patients were reviewed (1) to define the decision process regarding which guidance method (sonography v computed tomography) should be used on any given patient, and (2) to determine, once a guidance method was chosen, its accuracy and complication rate. Sonographic guidance (84%) proved to be an effective method for obtaining a correct diagnosis in 98% (110/112) of cystic masses and 79% (34/43) of solid masses. Computed tomography (16%) was used when sonography could not identify the mass or when the mass was small, deeply located, and often solid. Computed tomographic guidance provided a correct diagnosis in 100% (13/13) of cystic masses and 81% (13/16) of solid masses.
(JAMA 1983;250:2663-2666)