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Objective: The increasing quality of diagnostic ultrasound has resulted in the detection of greater numbers of potentially benign hepatic lesions. Current radiological practice requires contrast enhanced ultrasound, CT or MRI to confirm the diagnosis. Acoustic radiation force impulse (ARFI) elastography is an imaging technique measuring the elasticity of biological tissues. Recent technical advances in ultrasound have made it possible to generate shear waves, whose velocity in the liver is proportional to the degree of hepatic elasticity. Methods: This shear wave velocity (SWV) may be used as a marker for both focal and diffuse liver pathology.We used this technique to examine patients with normal livers and those with haemangiomata and metastases. Results: Patients with normal ultrasound examinations and normal liver enzymes, n=99, had SWVs of 1.24±0.23 m s-1 (mean ± standard deviation) independent of site of measurement, age or gender. Results of SWV measurements in haemangiomata, n=35, produced values of the same order, 1.35±0.48 m s-1. In contrast, patients with metastases, n=10, had SWVs of 4.23±0.59 m s-1. With a cut-off value of 2.5 m s-1, the sensitivity and specificity for haemangiomata were 97.1% and 100%, respectively, with an area under the curve of 0.999. Conclusion: ARFI elastography with SWV measurements is a promising new technique which could replace invasive investigations for benign hepatic lesions. [ABSTRACT FROM AUTHOR]

Romano–Ward syndrome (RWS), the autosomal dominant form of the congenital long QT syndrome, is characterised by prolongation of the cardiac repolarisation process associated with ventricular tachyarrhythmias of the torsades de pointes type. Genetic studies have identified mutations in six ion channel genes, KCNQ1, KCNH2, SCN5A, KCNE1 and KCNE2 and the accessory protein Ankyrin-B gene, to be responsible for this disorder. Single-strand conformation polymorphism (SSCP) analysis and subsequent DNA sequence analysis have identified a KCNQ1 mutation in a family that were clinically conspicuous due to several syncopes and prolonged QTc intervals in the ECG. The mutant subunit was expressed and functionally characterised in the Xenopus oocyte expression system. A novel heterozygous missense mutation with a C to T transition at the first position of codon 343 (CCA) of the KCNQ1 gene was identified in three concerned family members (QTc intervals: 500, 510 and 530 ms, respectively). As a result, proline 343 localised within the highly conserved transmembrane segment S6 of the KCNQ1 channel is replaced by a serine. Co-expression of mutant (KCNQ1-P343S) and wild-type (KCNQ1) cRNA in Xenopus oocytes produced potassium currents reduced by ≈92%, while IKs reconstitution experiments with a combination of KCNQ1 mutant, wild-type and KCNE1 subunits yielded currents reduced by ≈60%. A novel mutation (P343S) identified in the KCNQ1 subunit gene of three members of a RWS family showed a dominant-negative effect on native IKs currents leading to prolongation of the heart repolarisation and possibly increases the risk of malign arrhythmias with sudden cardiac death. [Copyright &y& Elsevier]