Scrubbing needles: a simple and costless technique to improve needle tip visibility during US-guided liver interventions.

AIMS: To evaluate the echogenicity of a commercially available needle, modified on the tip, by comparing two groups of patients undergoing to percutaneous biliary drainage. METHODS: In this retrospective analysis 16 percutaneous transhepatic biliary drainage (PTBD) procedures performed on 16 oncologic patients were evaluated. Patients were randomly divided into two groups of eight subjects each; in the first group, a standard needle was adopted (group A); in the second group, the needle was manually modified to create a rough surface (group B), by scrubbing the tip with an 11 scalpel blade for 150 s all around its surface. To objectively quantify US needle tip visibility, the contrast-to-noise ratio (CNR) was calculated analyzing B-mode images by positioning region of interests in correspondence of needle tip and liver parenchyma. RESULTS: Needle tip echogenicity was significantly higher in group B where the needle tip was modified compared to control group A (p value = 0.014). CNR, considered to objectively evaluate differences among needle tip echogenicity, was significantly higher in group B with respect to control group A (p value = 0.018). CONCLUSIONS: The proposed method, scrubbing a 22 gauge commercially available needle tip with a scalpel blade, represents an effective technique to improve needle visibility during US-guided punctures of the liver.