Ultrasound gel causes fine needle aspiration artifact? A clear choice

Ultrasound-guided fine needle aspiration (FNA) is a commonly employed tool in cytopathologic practice. Artifacts resulting in misinterpretation of specimens have been noted with various ultrasound gel media. Our purpose was to perform a prospective human cadaveric study of this phenomenon to identify a low-cost solution that eliminates the artifact.

Three separate ultrasound-guided FNAs were performed on the thyroid and parotid glands in situ of a fresh human cadaver using three different types of ultrasound gel media. Slides were prepared in standard fashion (Quik-Diff and Papanicolaou stains). Two cytopathologists subsequently analyzed the slides for the presence of any artifact interfering with their ability to visualize and interpret the cellular aspirate material.

Two of the three gel media revealed significant artifacts mimicking apoptosis, necrosis or colloid, making it difficult to visualize the cellular components and differentiate the artifact from the thyroid colloid. One gel medium did not show any significant artifact, and there was no discernable difference in its quality with regard to the ultrasound image during FNA procedures.

Ultrasound gels can be associated with a significant artifact in FNA specimens. To eliminate this artifact, which may alter the adequacy, diagnosis or cytologic appearance, we confirm a specific gel type that is useful for ultrasound-guided FNAs.