Modern multidetector CT (MDCT) has led to improvements in lesion detection of benign as well as malignant abdominal tumours [1]. The ability to scan through an abdomen in seconds has also permitted multiphasic examinations, but there is a radiation dose cost to the patient [2] as a consequence of using these new and established abdomen protocols. Some recent approaches to liver and abdominal CT dose reduction have included noise [3-4] and other adaptive filters [5-6] in an effort to address image noise in low dose...

Phantom design - Format Clinically liver radiodensities were measured at a little under 100 HU using the draw and analysis tool in eFilm software (Merge Healthcare;Milwaukee,WI). In the past a number of different materials have been investigated for use as tissue mimicking media for inclusion in CT test phantoms [13]. Our phantom was constructed using Poly(methyl methacrylate) (PMMA) with a radiodensity of 120 HU, which was of the correct order of magnitude for soft tissues that include the liver. PMMA was also selected as the...

(a) Images of the discs were reconstructed successfully with all scanners and modalities (Figure 6). High contrast was achieved with the phantom in air and a CT of disc 1 is included in Figure 6(a). All features in the disc were visible including the smallest hole with a diameter of 1 mm, the two holes with a diameter of 3 mm and the three holes with varying paths through the disc and a diameter of 5 mm. Identification and orthogonal orientation markers on the disc...

High contrast (test phantom in air) and low contrast (test phantom in water) feature images have been produced successfully demonstrating the suitability of the phantom in both CT and MRI, its extremes of performance and feature detectability when reporting. The test phantom itself is simple, cost-effective, but most importantly was designed to overcome the learning effects during reporting which are a problem in phantoms with fixed feature geometry and patterns that can be learnt and anticipated [14-15]. With our new test phantom the ability to...

Stuart Meeson PhD, Visitor working in Radiology Group, Nuffield Department of Surgical Sciences, University of Oxford, Oxford MRI Centre, John Radcliffe Hospital, Oxford OX3 9DU, UK; [email protected] Steven D Turnbull MSc, formerly Radiology Group, Nuffield Department of Surgical Sciences, University of Oxford, Oxford MRI Centre, John Radcliffe Hospital, Oxford OX3 9DU, UK. Stephen J Golding MA FRCR, Radiology Group, Nuffield Department of Surgical Sciences, University of Oxford, Oxford MRI Centre, John Radcliffe Hospital, Oxford OX3 9DU, UK; [email protected]

Hammerstingl RM, Vogl TJ. Abdominal MDCT: protocols and contrast considerations. Eur Radiol. 2005;15 Suppl 5:E78-90. Spielmann AL. Liver imaging with MDCT and high concentration contrast media. Eur J Radiol. 2003;45 Suppl 1:S50-2. Kanal KM, Chung JH, Wang J, Bhargava P, Kohr JR, Shuman WP, Stewart BK. Image noise and liver lesion detection with MDCT: a phantom study. Am J Roentgenol. 2011;197:437-41. Wessling J, Esseling R, Raupach R, Fockenberg S, Osada N, Gerss J, Heindel W, Fischbach R. The effect of dose reduction and feasibility of...