Yang Shin Park MD, Presenter: Nothing to Disclose

Chang Hee Lee MD, Abstract Co-Author: Nothing to Disclose

Jong Mee Lee, Abstract Co-Author: Nothing to Disclose

Jae Woong Choi MD, Abstract Co-Author: Nothing to Disclose

Kyeong Ah Kim MD, Abstract Co-Author: Nothing to Disclose

Cheol Min Park MD, Abstract Co-Author: Nothing to Disclose

Low tube voltage CT is useful in the evaluation of hypervascular hepatocellular carcinoma. However, image quality of hepatic arterial phase can vary depending on patient body habitus. Therefore, the purpose of our study was to evaluate which of patient body habitus factors have more impact on image quality of low tube voltage CT performed during the hepatic arterial phase.

Ninety-seven patients (66 men, 31 women; age range, 26-78 years) who underwent clinically indicated liver dynamic CT examination were enrolled in this study. Low tube voltage (80 kVp), low tube current (277-337 mAs) CT was performed in the late hepatic arterial phase using a 320-detector row scanner with adaptive iterative dose reduction (AIDR) 3D reconstruction. Patient body habitus was measured by using weight, body mass index (BMI), muscle volume (MV) of the abdominal wall, and longest lateral width (LW) of the abdomen. On hepatic arterial phase, the mean image noise and contrast-to-noise ratios (CNR) for the aorta and liver were assessed. Correlation between body habitus factors and image quality parameters was evaluated.  

In all patients, the image noise and CNRs for the aorta and liver had strongest correlation with MV (r = 0.68, -0.59, -0.28). In subgroup analysis, image noise was significantly correlated with weight, BMI, MV, and LW in men (r = 0.50, 0.40, 0.59, and 0.49), whereas image noise was significantly correlated with only MV in women (r = 0.73). In addition, the significant correlation was noted only between the image noise and MV (r = 0.45 and 0.77) in larger men (BMI >= 25) and smaller women (BMI < 25), while image noise was correlated with weight and MV (r = 0.52 and 0.45) in smaller men and no relationships in larger women.

Contrary to the prevailing thought about BMI as determinant for patient stratification, MV shows strongest correlation with image noise and CNR in the hepatic arterial phase using low tube voltage CT.  

With the use of MV as a determinant in indivisualized protocol or patient selection to perform low tube voltage CT during hepatic arterial phase, acceptable image quality can be achieved with diagnostic improvement for hypervascular hepatic tumor and radiation dose reduction.

Park, Y, Lee, C, Lee, J, Choi, J, Kim, K, Park, C, Effect of Body Habitus on Image Quality of Low Tube Voltage CT during Hepatic Arterial Phase: Is BMI Still Most Influential Factor?.  Radiological Society of North America 2014 Scientific Assembly and Annual Meeting, - ,Chicago IL. http://archive.rsna.org/2014/14016941.html