Andrew Molyneux


“Angiographic perfection at the expense of a significant clinical complication may not be the best outcome for the patient,” Andrew Molyneux, now senior clinical research fellow, University of Oxford, UK, and formerly honorary consultant neuroradiologist, North Bristol NHS Trust, Frenchay Hospital, and Oxford Radcliffe Hospitals, tells NeuroNews. Molyneux has published widely on many aspects of interventional neuroradiology and intracranial aneurysm treatment in particular, being co-principal investigator of the landmark International Subarachnoid Aneurysm Trial (ISAT) and other major trials.

How did you come to choose medicine? What drew you to neuroradiology?


Originally, in school, I had wanted to join the Navy, but it was suggested that my talents would be better utilised in other fields. It was a wise choice as I get sea-sick. Medicine and science always interested me and I ended up going to Cambridge to study medicine.

Then, after having spent time in New Guinea, my wife and I returned to the UK when my father died and I decided to pursue training in radiology rather than tropical medicine and return overseas.

I started training in the pre-CT era—yes, that long ago! The practical aspects and diagnostic challenges of neuroradiology suited me. Then the introduction of cross-sectional imaging in the form of early CT head scanners started the technical revolution in imaging, which has continued apace.

Who were your mentors in the field and what do you still remember from their wisdom?


My immediate mentor was Philip Sheldon, a delightful and skilled early pioneer of neuroradiology. He was a superb observer, decisive and a good clinician. I guess a thorough understanding of the clinical aspects of the subject that you are dealing with is the important learning point for any neuroradiologist. The other great teacher and mentor has been my neurosurgical colleague for many years, Christopher Adams. He encouraged and supported me, particularly in the development of interventional techniques in neurovascular disease. He taught me the important KISS principle, in this case—Keep It Simple and Safe.

You spent 18 months in Papua New Guinea, including in a remote Highland Hospital, what did you gain from your experiences there?

This was a transformative experience for a young doctor! I was one of three doctors serving a district of 200,000 people, doing everything from Caesarean sections, anaesthetics to autopsies, plus dealing with malaria and syphilis! An experience like this teaches flexibility, tolerance and respect for other cultures. The ability to get on with and respect others was essential, as was coping as best you could in challenging circumstances.

Being among the first in Europe to use platinum coils to treat otherwise untreatable cerebral aneurysms and one of the first in Europe to use detachable platinum coils, what are the technical innovations that have influenced your career? 

My interventional career started with making our own detachable balloons to treat carotid-cavernous fistulae! When wire-guided microcatheters became available, along with tiny-fibred platinum coils, that we could deliver through the catheters it was the start of a revolution. It was a natural progression to use the free pushable coils to treat otherwise untreatable aneurysms. The intervention of the Gugliemi Detachable Coil was the revolution we had been waiting for. The rest is history.

Over the last 30 years, how has the treatment of intracranial aneurysms changed?

It has been revolutionised. From a situation where all aneurysms were being treated surgically to now where over 80% can be treated without a craniotomy is extraordinary in the space of less than 20 years. Sadly, for a variety of reasons, patients in some countries do not have the option of coiling treatment, either because it is not being offered, because they are not informed about the option, or in many cases because of the costs associated with coils.

What are three lessons you would like to share with other neurointerventionists based on your experience of treating well over 1,200 intracranial aneurysms?


  • The enemy of good is perfect.
  • Angiographic perfection at the expense of a significant clinical complication may not be the best outcome for the patient!
  • Always keep in mind the clinical goal of the treatment of an aneurysm. It is nearly always to prevent a future aneurysm rupture. A satisfactory occlusion, even if it is not perfect angiographically, appears to achieve this objective. The number of late re-bleeds in ISAT is exceptionally low and it is likely that many of the patients will have imperfect angiograms.

One of your key interests has been the development of science and practice of interventional neuroradiology, primarily in the treatment of cerebral aneurysms and brain arteriovenous malformations by endovascular techniques…

Medicine always needs to move on and evolve. I have been fortunate to be in a field where it has been possible to completely change worldwide (almost) clinical practice. The evidence of the improved clinical outcomes of aneurysm coiling is overwhelming. This is less the case for brain arteriovenous malformations: the improvement in stereotactic radiation/gamma knife and the finding that delayed rupture of an arteriovenous malformation may be higher after embolisation raises questions over the exact role of embolisation in brain arteriovenous malformations management.

In your view, what were the key findings from ISAT for which you are co-principal investigator?

They were quite simple, even in the period between 1994 and 2002, when the imaging, catheter, coil technology and expertise were all much less developed: coiling significantly reduced the number of dead or disabled patients after cerebral aneurysm rupture compared with clipping. Similar clinical benefits have been found in a recently published study from a major US neurosurgical centre. The recently published coiling outcomes from randomised, controlled trials have shown still further improvements in clinical outcomes. The risks of late re-bleeding are very low after both techniques and will never counteract the improved clinical outcomes. Coordinating a study that has changed worldwide clinical practice is a rewarding and humbling experience.

You have been involved in setting up more than one interventional neuroradiology service—what are the key aspects to consider while doing this?

Interventional neuroradiology (endovascular neurosurgery), is a team effort. To be successful, you need people to work together and support each other. This means everyone—from ancillary, secretarial, nursing and radiographic staff and particularly supportive neurosurgical and neurological colleagues—needs to work as a team. Things will go wrong and you will need their help and support, and sometimes it may be the other way round. It is also important to accept that there may be other ways to deal with cases, and that individual techniques may vary. Mutual respect and good communication are crucial for success.

Can you describe a memorable case and how interventional neuroradiology came to the rescue?

The most memorable case was of a gentleman who had a recurrent carotid cavernous fistula dating from the mid 1960s when he had fallen off his motor-scooter. I saw him about 20 years later in the early 1980s. He had had three operations, including occlusion of his common carotid, his extracranial internal carotid and his intracranial carotid, which had all failed to close the fistula. He had a dreadful proptosis, huge forehead veins and was completely blind in that eye. His internal carotid had re-canalised via C1–C2 collaterals and emptied into the large fistula. My surgical colleague did an operative approach to the carotid; we put a sheath in and then treated the fistula with detachable balloons, completely occluding it. His eye was better in a week, and he looked completely normal at one year. He had a new baby then. I saw him more than 20 years later when his daughter was 21! The balloons were still inflated.

What are three key questions in interventional neuroradiology that you would like to see answered?


  • What is the future role of flow diverters? We need to define the role of these devices. Do they increase procedural risk? If so, for what clinical gain? Properly designed randomised studies will be essential if they are to be used in aneurysms suitable for coiling, if they are to be treated with these devices on a wide scale. There is a real danger these devices are becoming part of a typical hype cycle.
  • What is the role of endovascular treatment in acute stroke due to carotid or middle cerebral occlusion? There are now several randomised, controlled trials underway in this area addressing these questions properly. If they show, as many think they will, that the treatment can improve outcomes dramatically provided it can be delivered in a timely fashion, then it will have massive implications for the specialty.
  • Which unruptured aneurysm should be treated? Sadly, a randomised trial in this area failed to recruit sufficient patients. It seems we will be unlikely to get Grade 1 evidence. Most unruptured aneurysms never bleed, finding a way of predicting which ones will rupture would be a massive step.

Which new techniques/technologies are you watching closely?

Obviously flow diverters are the technology of the moment. Whether this technology is in the Gartner Hype cycle remains to be seen. The main expansion is likely to be in stroke treatment. Most colleagues believe this can be made to work and improve outcomes. Many devices will be developed and tried. Stent-retrievers seem best at present. The ability to restore some blood flow through a previously occluded vessel early on in the procedure may be a significant benefit in reducing the extent of infarction.

Interests outside of medicine…

Supporting the family is my main priority as they move on to have families of their own. I like to try to keep fit. As I get older, I realise you need to either use it or lose it! Maintaining flexibility, so the golf swings stays reasonable, and staying fit enough for challenging skiing (preferably deep powder snow). Regular gym classes have improved my fitness and sense of rhythm (my wife would say better late than never!). Hopefully, I will be able to do more proper travel and not just traveling to conferences and staying in a hotel that could be anywhere.


Current positions

Senior clinical research fellow, University of Oxford, Oxford, UK

Honorary consultant neuroradiologist, North Bristol NHS Trust, Bristol, UK


Previous positions


1977–1979 Senior registrar in Radiology, Oxfordshire Health Authority

1978–1979 Visiting instructor in Radiology, University of Colorado Medical Centre, Denver, Colorado

1979–2004 Consultant neuroradiologist, Radcliffe Infirmary, Oxford

2004–2008 Consultant neuroradiologist, Frenchay Hospital, Bristol


1971, 1972 MA MB BChir Cambridge   

1974           D Obst RCOG

1977           FRCR 

National and International positions (selected)

1990–1996 Chairman, UK Neurointerventional group

1990 Chairman, Scientific Programme Committee Symposium


1995 Windemere Visiting Professor, Monash Medical Centre, Melbourne, Australia

2002–2004 President, British Society of Neuroradiologists

2002–2005 Royal College of Radiologists representative, Royal College of Physicians, Stroke Guidelines Working Party

2006–2008 Member, Stroke Guidelines Development Group, National Institute for Clinical Excellence (NICE)


Teaching, research and academic work


1994–2013 Co-principal investigator and grant holder of the UK Medical Research Council, International Subarachnoid Aneurysm Trial (ISAT)

1998–2004 International study of Unruptured Intracranial Aneurysms (ISUIA). Executive committee member and investigator of the long-term natural history study coordinated by the Mayo Clinic, Rochester, USA. Funded by the NINDS

  • Member, Writing Committee of the American Stroke guidelines committee for the management of subarachnoid haemorrhage, Stroke Council, American Heart Association
  • 2000–2002 Royal College of Radiologists nominee on the Stroke Guidelines group of the Royal College of Physicians
  • Member of the Stroke Guidelines Development Group, National Institute for Clinical Excellence  Member Data Monitoring and Safety Committee, International Carotid Stent Study (ICSS)