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Objective: To develop a phantom system which can be integrated with an automated injection system, eliminating the experimental variability that arises with manual injection; for the purposes of pulse sequence testing and metric derivation in hyperpolarised 13 C-MR., Methods: The custom dynamic phantom was machined from Ultem and filled with a nicotinamide adenine dinucleotide and lactate dehydrogenase mixture dissolved in phosphate buffered saline. Hyperpolarised [1- 13 C]-pyruvate was then injected into the phantom ( n = 8) via an automated syringe pump and the conversion of pyruvate to lactate monitored through a 13 C imaging sequence., Results: The phantom showed low coefficient of variation for the lactate to pyruvate peak signal heights (11.6%) and dynamic area-under curve ratios (11.0%). The variance for the lactate dehydrogenase enzyme rate constant (kP) was also seen to be low at 15.6%., Conclusion: The dynamic phantom demonstrates high reproducibility for quantification of 13 C-hyperpolarised MR-derived metrics. Establishing such a phantom is needed to facilitate development of hyperpolarsed 13 C-MR pulse sequenced; and moreover, to enable multisite hyperpolarised 13 C-MR clinical trials where assessment of metric variability across sites is critical., Advances in Knowledge: The dynamic phantom developed during the course of this study will be a useful tool in testing new pulse sequences and standardisation in future hyperpolarised work.

(1) Background: Intestinal failure-associated liver disease (IFALD) in adults is characterized by steatosis with variable progression to fibrosis/cirrhosis. Reference standard liver biopsy is not feasible for all patients, but non-invasive serological and quantitative MRI markers for diagnosis/monitoring have not been previously validated. Here, we examine the potential of serum scores and feasibility of quantitative MRI used in non-IFALD liver diseases for the diagnosis of IFALD steatosis; (2) Methods: Clinical and biochemical parameters were used to calculate serum scores in patients on home parenteral nutrition (HPN) with/without IFALD steatosis. A sub-group underwent multiparameter quantitative MRI measurements of liver fat fraction, iron content, tissue T1, liver blood flow and small bowel motility; (3) Results: Compared to non-IFALD ( n = 12), patients with IFALD steatosis ( n = 8) demonstrated serum score elevations in Enhanced Liver Fibrosis ( p = 0.032), Aspartate transaminase-to-Platelet Ratio Index ( p < 0.001), Fibrosis-4 Index ( p = 0.010), Forns Index ( p = 0.001), Gamma-glutamyl transferase-to-Platelet Ratio Index ( p = 0.002) and Fibrosis Index ( p = 0.001). Quantitative MRI scanning was feasible in all 10 sub-group patients. Median liver fat fraction was higher in IFALD steatosis patients (10.9% vs 2.1%, p = 0.032); other parameter differences were non-significant; (4) Conclusion: Serum scores used for non-IFALD liver diseases may be useful in IFALD steatosis. Multiparameter MRI is feasible in patients on HPN.