Leah Muhm Lin MD, Presenter: Nothing to Disclose

Aysegul Solmaz Tuncer, Abstract Co-Author: Nothing to Disclose

Lauren L. Ihde MD, Abstract Co-Author: Nothing to Disclose

Alison Wilcox MD, Abstract Co-Author: Speaker, Toshiba Corporation

Farhood Saremi MD, Abstract Co-Author: Nothing to Disclose

Christopher Lee MD, Abstract Co-Author: Nothing to Disclose

To compare radiation dose information, procedure duration, complication rate, and diagnostic yield for CT-guided transthoracic biopsies performed with 120 kV versus 100 kV tube voltage.

215 consecutive CT-guided transthoracic biopsies were performed from January 2009 through January 2013 at our institution. In July 2011, a transition was made from performing biopsies with 120 kV to 100 kV tube voltage. Tube current was arbitrarily set by the technologist. All biopsies were performed without use of CT fluoroscopy. Procedure duration was calculated on the basis of the time stamps of the first and last CT images acquired during the procedure. Complications were recorded and stratified into minor and major complications. Diagnostic yield was assessed by reviewing histopathology records.

90 biopsies were performed with 120 kV, and 125 biopsies were performed with 100 kV. The average dose-length product (DLP) for the 100 kV biopsies was 345.1 mGy-cm, while the average DLP for the 120 kV biopsies was 842.9 mGy-cm, a dose savings of 59.1%. The average procedure duration of the 120 kV biopsies was 50 minutes, and the average duration of the 100 kV biopsies was 48 minutes. The overall complication rate for the 100 kV biopsies was 40.8%, while the complication rate for the 120 kV biopsies was 25.6%. However, after including only those biopsies performed solely by attending radiologists, the overall complication rate for the 100 kV biopsies dropped to 34.4%, while the complication rate for the 120 kV biopsies was 24.7%, which was not statistically significant. The major complication rates for the 100 kV and 120 kV biopsies in this sub-cohort were 3.2% and 4.1%, respectively. A definitive diagnosis was obtained from the 100 kV biopsies 86.4% of the time, while a definitive diagnosis was obtained from the 120 kV biopsies 83.3% of the time.

Performing CT-guided transthoracic biopsies with low tube voltage conferred a significant radiation dose savings without increased procedure duration. Although there was a trend toward increased complications at 100 kV, this was not statistically significant, and the rate of major complications was essentially the same. The rate of definitive diagnosis was, likewise, similar in both groups.

Our results suggest that CT-guided transthoracic biopsies should be routinely performed utilizing 100 kV tube voltage.

Lin, L, Solmaz Tuncer, A, Ihde, L, Wilcox, A, Saremi, F, Lee, C, Comparison of 120 kV and 100 kV Scan Parameters for CT-guided Transthoracic Biopsy.  Radiological Society of North America 2013 Scientific Assembly and Annual Meeting, December 1 - December 6, 2013 ,Chicago IL. http://archive.rsna.org/2013/13044197.html