CT-guided liver biopsy: correlation of procedure time and radiation dose with patient size, weight, and lesion volume and depth

Abstract

Purpose The purpose of this study was to retrospectively evaluate the effect of various factors, including overall patient size, weight, and individual lesion characteristics, on the radiation dose and procedure time required to successfully perform computed tomography (CT)-guided liver lesion biopsies. Materials and Methods This Institutional-Review-Board-approved study included 209 patients (average age, 59 years; range, 19–86 years; 105 males, 104 females) who underwent CT-guided liver lesion biopsy on a four-slice multidetector row CT scanner (LightSpeed Qx/i; GE Healthcare, Milwaukee, WI). Medical records and images were retrospectively reviewed to obtain the following data: (a) patient weight, (b) patient size, (c) lesion volume, (d) lesion depth, (e) CT dose index (CTDI) and effective radiation dose, and (f) procedure time. Statistical analysis was performed with multiple linear regression to assess the effect of various parameters on radiation dose and procedure time. Results CTDI was significantly correlated with patient weight ( P<.01), size ( P=.03), and lesion volume ( P<.01). The total effective radiation dose was significantly correlated with patient size ( P<.01) and lesion depth ( P<.01). Total procedure time was significantly correlated with lesion volume ( P<.01) and depth ( P<.01). There was a positive correlation between procedure time and effective radiation dose ( r 2=.57). Conclusion In the current study, CT-guided liver lesion biopsy patient radiation dose was associated with both overall patient-specific features (weight and size) and specific lesion characteristics; however, the procedure duration was determined by lesion characteristics (lesion volume and depth) alone.