Imaging assessment

News release from the National Coordinating Centre for Health Technology Assessment

17 May 2006

HTA research published in The Lancet (6 May) suggests that less invasive methods of testing for carotid stenosis (the narrowing or blockage of the arteries that supply blood to the brain, which can cause stroke) could replace the reference standard for assessment.

It is important that carotid stenosis is diagnosed at the right stage, as surgery (carotid endarterectomy) at the right time reduces the risk of stroke dramatically. Accurate imaging is essential to achieve this and to avoid operating on patients with less severe stenoses in whom the risk of surgery may outweigh the benefit. Intra-arterial angiography (IAA), the routine imaging test for carotid stenosis, carries a 1-2% risk of stroke, and less invasive tests have improved to the extent where they could now replace it altogether.

The research team, led by Professor Joanna Wardlaw, Department of Clinical Neurosciences, University of Edinburgh , investigated whether single or a combination of less invasive tests could be used in place of IAA. The team consulted with a panel of experts in stroke, imaging and vascular surgery, as well as evaluating the research evidence around different types of imaging for carotid stenosis, and their cost-effectiveness. These include ultrasound ( US ), magnetic resonance angiography (MRA), CT angiography (CTA) and contrast enhanced MRA (CEMRA).

The researchers concluded that, in the UK , less invasive tests could be used in place of IAA if radiologists trained in carotid imaging are available, although data on combinations of tests were too sparse to be reliable. This research is due to be published in full in the Health Technology Assessment series. For project details, visit http://www.hta.ac.uk/project/1311.asp

Notes for editors


  1. The HTA programme is a programme of the National Institute for Health Research (NIHR) and produces high quality research information about the effectiveness, costs, and broader impact of health technologies for those who use, manage and provide care in the NHS. It is the largest of the NIHR programmes and publishes the results of its research in the Health Technology Assessment journal, with more than 400 issues published to date. The journal’s 2007 Impact Factor (3.87) ranked it in the top 10% of medical and health-related journals. All issues are available for download free of charge from the website, www.hta.ac.uk The HTA programme is coordinated by the National Coordinating Centre for Health Technology Assessment (NCCHTA), based at the University of Southampton.
  2. The National Institute for Health Research provides the framework through which the research staff and research infrastructure of the NHS in England is positioned, maintained and managed as a national research facility.  The NIHR provides the NHS with the support and infrastructure it needs to conduct first-class research funded by the Government and its partners alongside high-quality patient care, education and training.  Its aim is to support outstanding individuals (both leaders and collaborators), working in world class facilities (both NHS and university), conducting leading edge research focused on the needs of patients. www.nihr.ac.uk

Contact details

Naomi Stockley, Programme Manager (Communications)
Telephone: 02380 595 646, Email: ns5@soton.ac.uk

Helen Nikandrou, Assistant Programme Manager (Communications)
Telephone: 02380 595 584, Email: h.nikandrou@soton.ac.uk

Advanced search How to use the search function