Brilliance 64 slice scanner

Liver fat was estimated with established criteria validated by other groups using liver biopsy as the gold standard (52 (link)–54 (link)). Specifically, using a Phillips Brilliance 64-slice scanner, a single cross-sectional 5-mm-width CT scan (of 120 kVp, 100 mA) at the intervertebral disc space between T12 and L1 was obtained to image both the liver and the spleen. Data obtained from CT scans were analyzed using E-Film software. Three ROIs were placed on the liver (posterior right lobe, anterior right lobe and left lobe), and 1 ROI was placed on the spleen. Each ROI measured a minimum of 1 cm² and excluded all major blood vessels. ROI attenuation was documented in HU. MLA was calculated using ROIs in the liver, and the L/S ratio was calculated using ROIs in the liver and the spleen. MLA ≤ 40 HU and L/S ratio ≤ 1 both indicate moderate-to-severe fatty liver.

Abdominal CT scans (Phillips Brilliance 64-slice scanner) were undertaken to measure hepatic steatosis and visceral adiposity. A calibration control (phantom) was placed between the table and the participant’s back during the CT scan and this was used to standardize all liver measurements. With the participant in a supine position, a single 5 mm slice (120 kVp, 100 mA) was taken at the T12/L1 intervertebral disc space to include both the liver and the spleen. The scan was not contrast-enhanced. A second scan was located at the L4/L5 disc space to measure total abdominal and visceral fat area, mass and volume.

CT scans were performed on Siemens 128-slice scanners (Siemens, Erlangen, Germany) at Papworth Hospital, Cambridgeshire and Liverpool Heart and Chest Hospital (LHCH). In the initial phase of the trial, from November 2011 to December 2011, a Philips Brilliance 64 slice scanner (Philips, Best, The Netherlands) was used at LHCH, using the same acquisition parameters.
Thoracic CT images were obtained from lung apices to bases, during suspended inspiration, in a single breath hold and without the administration of intravenous contrast. Images were reconstructed at 1 mm thickness at 0.7 mm increments, using a moderate spatial frequency kernel reconstruction algorithm. Acquisition parameters (kVp and mAs) varied according to body habitus to achieve a CT dose index below 4 milliGray.