Assessing the Effect of Weight-Based Protocol Modifications to Lower Dose for CT-Guided Hepatic and Renal Tumor Radiofrequency Ablations.

Abstract

OBJECTIVE:

This study assessed radiation dose after CT-guided percutaneous radiofrequency ablations (RFAs) of hepatic and renal tumors and the effect of weight-based CT protocol modification for lowering overall dose in these procedures.

MATERIALS AND METHODS:

CT-guided RFA for renal and hepatic ablations performed from January 1, 2009, through December 31, 2009, were retrospectively reviewed (90 men and 48 women; age, 42-81 years). The radiation dose was recorded during each of the following steps: planning, performing, and postprocedure. Weight-based protocol modification changes in tube voltage and tube current were then applied to renal and hepatic ablations performed subsequently (18 men and 11 women; age, 48-82 years). Image quality, needle localization, lesion detection, ability to detect complications, and overall operator satisfaction were noted for each case (score, 1-5). Dose reduction after modification was then calculated.

RESULTS:

Retrospective analysis found a mean (± SD) overall CT dose index (CTDI) for CT-guided RFA to be 16.5 ± 2.3 mGy. After protocol modification, the mean CTDI decreased to 6.63 ± 0.67 mGy, a 59.6% reduction overall; for hepatic ablations, the reduction was 65.96% (p < 0.0001) and the reduction for renal ablations was 38.97% (p = 0.0153). Image quality analysis showed high operator satisfaction (3-5), including adequate needle localization (4-5), lesion visibility (3-5), and high performer confidence (4-5). Higher dose reduction was noted for patients weighing more than 180 lb (82 kg) (p < 0.0001).

CONCLUSION:

Simple weight-based CT protocol modifications can significantly reduce radiation dose during CT-guided percutaneous ablations in the liver and kidneys without significantly sacrificing image quality.

• Authors: Supriya Gupta, Ronald S Arellano, Debra A Gervais, Dushyant V Sahani
• Journal: AJR. American journal of roentgenology (AJR Am J Roentgenol) Vol. 210 Issue 3 Pg. 657-662 (Mar 2018) ISSN: 1546-3141 [Electronic] United States
• PMID: 29323550 (Publication Type: Journal Article)

Topics

• Adult
• Aged
• Aged, 80 and over
• Catheter Ablation (methods)
• Female
• Humans
• Kidney Neoplasms (surgery)
• Liver Neoplasms (surgery)
• Male
• Middle Aged
• Radiation Dosage
• Radiography, Interventional (methods)
• Retrospective Studies
• Tomography, X-Ray Computed (methods)