(ChemotherapyAdvisor) – Use of a low-dose protocol for CT-guided lung-biopsy procedures resulted in a dose reduction of 66% and provided satisfactory imaging guidance, investigators reported during the Society of Interventional Radiology’s 37th Annual Scientific Meeting in San Francisco, CA, on March 25.
With the goal of decreasing radiation exposure to patients — a concern of both professional groups and society at large — they implemented a low-dose CT guidance protocol in August 2010 involving a 120kVp spiral acquisition with a pitch of 0.8 and 80mAs for planning, followed by sequential 100kVp and 80mAs acquisitions for guidance. All procedures were performed on a single 16-slice CT scanner (Somatom, Siemens Medical Solutions) and operators could determine the imaging volume to be scanned and modify the CT guidance protocol.
Data from 100 people, half of whom underwent CT-guided biopsies prior to the new protocol and half after the protocol went into effect, were reviewed.
The low-dose protocol significantly reduced the average dose-length product for lung-biopsy procedures from 747.9mGy*cm (range 121-5,559) to 251.8 mGy*cm (range 73–715) (P<0.0001). No significant difference in the number of CT acquisitions for needle guidance between groups (16.3 vs. 14.5) (P<0.21) was observed. Sequential scanning for needle guidance was utilized in 0 of 50 before and 50 of 50 procedures after implementation.