Needle Tip Echogenicity

Abstract

Bondestam S, Kreula J. Needle tip echogenicity: a study with real time ultrasound. Invest Radiol 1989;24:555–560. During ultrasound-controlled biopsy, the visualization of the needle tip is essential for its exact guidance. We constructed a testing device to simultaneously measure the needle tip echo (NTE) intensity of several needles. The following needle parameters were studied: the angle of incidence, the needle diameter, the needle tip bevel angle, and the orientation of the needle tip opening to the transducer. Measurements were made in A-mode using the highest amplitude peak of the NTE and in B-mode using the gray level histogram map from a fixed area around the NTE. There was a positive linear correlation between the intensity of the NTE and the angle of incidence in A-mode as well as B-mode. In A-mode a similar linearity was found between the NTE and the needle diameter, which in B-mode was exponential. However, the needle tip bevel angle did not affect the NTE. Rotating the needle around its longitudinal axis rendered the highest echo at an orientation of 180° from the transducer in A-mode as well as B-mode.