Now doing remote brain and spine surgery e-consultations

A brief note to say that I am now doing remote consultations including international second opinions using Trustedoctor.  I like the platform because it is secure and designed for clinicians and patients, enabling images and referral letters to be uploaded and gone through together.  I can draw on MRI scans in real-time to explain anatomy for example.  Here is a link if you want to book a consult:

I am still also using Zoom, Skype, MSTeams and offering face to face in person consultations if desired at 116 Harley Street.

And the busy NHS service at St George’s continues!



London Deep Brain Stimulation

Image 2019-02-13 13.49.55


Having been fortunate enough to have established the UK’s first high volume, academic deep brain stimulation service in over a decade at St George’s University Hospital in south west London in 2016,  it is humbling to have been awarded the opportunity to establish another high quality private neuromodulation clinic in central London’s Harley Street.  High tech, state of the art brain surgery requires considerable investment and faith by any hospital’s directors as well as the equipment and infrastructure of intensive care, specialist nursing and training.  In partnership with The London Clinic, we created London Deep Brain Stimulation, a multi-disciplinary team of experienced experts and friends:

Professor Tipu Aziz from Oxford University who trained me and pioneered deep brain stimulation (DBS) and lesions for movement disorders and pain in the UK in the 1990s.  His groundbreaking scientific research led to the establishment of subthalamic nucleus DBS for Parkinson’s disease and discovery of pedunculopontine nucleus DBS for freezing and falling in Parkinson’s disease.  He has one of the largest surgery for movement disorders and certainly the largest DBS for pain experience in the world.  He is a Fellow of the Academy of Medical Sciences and Fellow of the Faculty of Pain Medicine of the Royal College of Anaesthetists.  This year he will be the first neurosurgeon still in active clinical practice to be awarded the prestigious Medal of the Society of British Neurological Surgeons, a testament to his brilliance.  He continues to be very research active, currently running promising trials in DBS for anorexia nervosa and post-stroke pain.

Professor Dipankar Nandi from Imperial College London, also trained by Professor Aziz and who did the pioneering pedunculopontine nucleus DBS research under his supervision and heads the Imperial College functional neurosurgery service.

Dr Moein Tavakkoli, consultant anaesthetist and pain doctor at University College Hospitals and St George’s Hospital.

Dr. Dominic Paviour, consultant neurologist at St George’s University Hospital, clinical lead of our advanced movement disorders treatment team there.

me, consultant neurosurgeon and director of functional neurosurgery at St George’s University Hospital.

As a charity investing in clinical research, The London Clinic is a really good fit for our team, standing out from other purely commercial Harley Street and central London private hospitals.  We treated a handful of international patients in 2018 with DBS at The London Clinic with Parkinson’s disease, dystonia and chronic pain, and many more with spinal cord stimulation.  We use all the major manufacturers (Abbott, Boston Scientific, Nevro, Medtronic), choosing system and model based on the clinical team’s expert opinion and patient choice.  We have done charitable surgeries and last year I was the first neurosurgeon in the UK to implant a new, cost-effective DBS system made in China.  Our work was featured in this month’s Prognosis Magazine (p48), the journal for the Harley Street medical area.  It has also been recently showcased in a video by the British engineering firm Renishaw, who make the DBS neurosurgical planning software that I frequently use.

We are happy to treat patients with deep brain stimulation, spinal cord stimulation or brain lesions both privately at The London Clinic and in the NHS and privately at St George’s.  See the London DBS website for more details.

dbs_operation_800.jpgThree ‘generations’ of directors of deep brain stimulation in their respective UK University Teaching Hospitals, operating together as a team for a good cause, making a tiny hole in the head of a charitably funded patient from the developing world during a minimally invasive DBS surgery.  Myself from St George’s University of London turning the drill, Prof. Dipankar Nandi from Imperial College London in the middle, and our mentor, Prof. Tipu Aziz from Oxford University on the right.

If you would like to donate to my research into deep brain stimulation and spinal cord stimulation, please contact the Neurosciences Research Foundation (NRF), a charity based at St George’s, University of London. If you would like to give in a tax-efficient manner please contact Carole Bramwell for further information or click here, quoting reference TAPAA (which is my research fund within the NRF).


Cervical disc replacement (arthroplasty)


Quite a few patients recently have asked me to perform cervical disc replacement (also known as arthroplasty).  It’s an operation I enjoy doing technically, but it got me thinking about whether the indications and evidence for its benefit have changed much over the last decade.  The surgery is similar to anterior cervical fusion, with a couple of extra steps and another 10-30 minutes to the 1-2 hour operation.  Disc replacement implants cost, at approximately £2000, around 10 times as much as fusion cages.  The National Institute of Clinical Excellence (NICE) and NHS England permit arthroplasty if patients have been discussed by several spinal surgeons at a multi-disciplinary team meeting (MDT) which we have weekly at St George’s (and admirably for the private sector fortnightly in The London Spine Clinic in 116 Harley Street).  In the private sector the cost becomes less of an issue and it’s more patient choice dependent (almost all insurers approve).

I performed St George’s Hospital’s first cervical arthroplasty in early 2017 on a patient with the unusual anatomical problem of three adjacent slipped discs bulging centrally backwards into the spinal cord causing signs and symptoms of chronic squashing (myelopathy).  My talented spinal surgeon colleague Matthew Crocker (also of Wimbledon Clinics) has recently performed another over a single level at St George’s.  Privately, I regularly perform single and two level arthroplasties at The London Clinic.

I was fortunate to have much of my Oxford neurosurgical training with Tom Cadoux-Hudson, a true master anterior cervical spinal surgeon under whose tutelage I became adept at performing three and four-level anterior cervical discectomy and fusion surgeries without plating quickly and safely through a minimally invasive and beautifully healing transverse skin incision in a natural neck crease.  Half a decade ago I presented internationally and published the results of our first 30 patients in Journal of Clinical Neuroscience and what became apparent were acceptable rates of adjacent level problems (6.7% after over five years) requiring an adjacent discectomy or same level problems needing further posterior decompression surgery (10% at close to four years).  I believe that patients presenting with 3 and 4 level disc disease requiring discectomy are predisposed, either by nature or nurture or both, to further degeneration and anything that can be done to minimise the chance of further surgery is desirable.

This led me to ‘hybridise’ the construct of the St George’s patient with three adjacent slipped discs, aiming to put two fusion cages at the bottom levels and an arthroplasty at the top to try to reduce the wear and tear on the disc above in my predisposed patient.  Adjacent segment disease (a symptomatic slipped disc at the level next to past cervical surgery) usually occurs at the disc above, most probably due to increased torque from free movement of the head on the body like a ball on a stick.

spine nerve

Interestingly the UK National Institute of Clinical Excellence (NICE) only really approves disc replacement for one and two levels (because that’s what published evidence is on), rather than for the indication of hybridising the third or fourth level in a multi-level affected, and hence unusually predisposed to adjacent disease, patient.  Cervical disc replacements have been around in some form or the other for three decades with increased uptake and new devices in the last decade following US FDA approval.  It is important to note that most of the trials of arthroplasty versus fusion needed for FDA approval were non-inferiority, i.e. they suggest that arthroplasty is at least as good as, but not necessarily better than fusion.  One parameter often cited is reduced neck pain, but some of the studies are flawed – for example measuring mobility in both groups when the fusion group has been put in hard collars (an unnecessary practice I don’t advocate) to aid fusion!  Several systematic reviews and meta-analyses suggest better outcomes from arthroplasty in terms of neck pain, arm pain and mobility, but there’s little data beyond half a decade of follow-up.

My take on it is that younger (i.e. in their 50s or less) more active adults who have arm pain from a trapped nerve (radiculopathy) and neck pain from a soft slipped disc of good disc height on MRI or X-ray are those who may benefit most from arthroplasty.  For arm pain alone and more laterally extruded or foraminal disc prolapses I think about posterior cervical foraminotomy as the operation of choice.  This is an operation frowned upon by many orthopaedic spinal surgeons for several reasons – firstly, reticence to use a microscope and small (1mm and 2mm) Kerrison rongeurs as a neurosurgeon would to delicately remove bone and ligament from the nerve, secondly a cultural dogma that an implant needs to be inserted into the patient, thirdly a belief in indirect decompression by height augmentation of the disc space.  It is also unusual for orthopaedic spinal surgeons to use a microscope for anterior cervical discectomy therefore many fear to open the ligament over the spinal cord and nerves to truly decompress them.

I am open-minded about arthroplasty in young adults with chronic spinal cord compression (myelopathy) provided there are few signs of joint damage (arthropathy) and loss of disc height, i.e. the joint is reasonably mobile to begin with.  The mobility conferred by a disc replacement is small therefore unlikely to exacerbate spinal cord compression after decompressive surgery.

Ultimately the spine is different from the hip or the knee where arthroplasty if possible is clearly better for function than fusion as those joints have large arcs of movement.  Each cervical spinal joint moves only a few degrees and its movement is compensated for by adjacent joints.  Almost all head on body (i.e. neck) movement occurs in the upper cervical spine rather than the lower cervical spine where arthroplasties are usually done.

I decide between posterior foraminotomy, anterior fusion and anterior arthroplasty in an informed discussion together with the patient based on their symptoms, signs, demographics, anatomy and preferences.  Review data from multiple studies suggests neck pain may be more improved by arthroplasty, more mobility maintained, adjacent segment wear and tear reduced and greater patient satisfaction compared to fusion at up to five years.  We all have cases who have done well for a decade or more and have heard of a few who have needed revision surgery, but nobody really knows what happens beyond half a decade yet.  Even the Philadelphia orthopaedic surgeon Alan Hilibrand, who coined the term “adjacent segment disease” in a seminal paper, is vague about evidence and indications.  Tissue reaction to the implant is extremely unlikely.  Bone growth elsewhere (heterotopic ossification) is possible.  The worst thing that could commonly happen is probably that the arthroplasty fuses after a few years but still does its job of getting rid of pain, numbness or weakness due to trapped nerves.  The reality is all three of these operations work quite well to relieve trapped nerves in the neck if patients are appropriately selected – and counselled for the small but serious risks of spinal surgery.

In terms of arthroplasty implants, at the moment I tend to use Mobi-C by Zimmer Biomet (which is widely used and NICE appraised) and M6C by Spinal Kinetics.  I was introduced to M6C by Khai Lam on my orthopaedic fellowship at Guy’s and St Thomas’, and I tried a few other brands training under Oxford neurosurgeon Simon Cudlip.  Both the implants I currently use are composite with plastic innards and metal ends interfacing with bone, reasonably priced for the UK market and have the desirable attributes of being quickly and easily inserted (with few extra steps over fusion surgery) compared to some competitors.  Mobi-C has some of the strongest evidence for superiority over fusion, a more versatile size range (good for petite females) and is less constrained in its movement whereas M6C seems perhaps sturdier so may suit the strapping rugby player or builder’s neck (although there’s no evidence for this and one could also make the opposite argument for wanting to bolster a slender neck more).

Below is a video of a three level disc replacement in action (shown by live intraoperative X-ray) demonstrating impressive preservation of mobility!

Deep brain stimulation treats high blood pressure (standing on giants’ shoulders)

The treatment involves inserting a thin wire electrode into the brain and connecting it to a battery-powered pacemaker

As an academic functional neurosurgeon implanting deep brain stimulators mainly for Parkinson’s disease and sometimes for tremor and dystonia, I was delighted to see recently published a case report of deep brain stimulation to treat high blood pressure.  The surgery was led by Mr. Nik Patel, a consultant neurosurgeon in Bristol and a friend whom I last saw over some huge plates of seafood and game in Cape Town half a decade ago.  He placed an electrode in the midbrain periaqueductal grey (PAG) matter in a woman with a blood pressure of 300/170 mmHg who had tried eight types of medicine, chronic baroreflex activation therapy and renal nerve ablation.  Her blood pressure initially became much lower at 170/110 a week after surgery, creeping up to 230/140 two years later, suggesting some long-term tolerance to the therapy.

The scientific paper was unusual in transcribing an interview between its author and an editor, and in that Nik was quick to acknowledge the basic science and human studies done in Oxford by Mr. Alex Green under Prof Tipu Aziz’ and Prof David Paterson’s supervision over a decade ago, and more recently my research under Alex Green’s supervision.  We were disappointed therefore to see newspapers such as The Express and The Daily Mail give no mention to over a decade’s research of ours that underpinned their first in man study.  While superficial journalism from the tabloids is not unusual, their articles mirror Bristol Hospital’s  and Bristol University’s press releases, neither of which make any mention of Oxford.

Self-promoting revisionist narratives are not uncommon either in science or in politics.  To repeat a quote from Indira Gandhi that my sister enjoyed,

There are two kinds of people, those who do the work and those who take the credit. Try to be in the first group; there is less competition there.

I have previously commented that modern biomedical science often progresses in small, incremental advances rather than Eureka moments and the Bristol institutions’ failure to acknowledge Oxford gives me an ideal opportunity to set the record straight and outline the incremental discoveries at Oxford that led to Nik’s elegant clinical study.  These were also coincidentally the subject of my Hunterian Professorial Lecture to the Society of British Neurosurgeons in 2014.  They can be summarised as follows.

In 2005 and 2006, we published that stimulation of the PAG during surgery in awake humans receiving DBS for chronic pain can elevate blood pressure if done dorsally and lower it if done ventrally.  Magnitude of blood pressure change correlated with magnitude of pain relief.  An important finding also published in 2006, this made the cover of the journal Pain.  These findings in 16 patients were the subject of Alex Green’s doctoral thesis with Tipu Aziz and won them numerous prizes from the American Congress of Neurological Surgeons, the Royal Society of Medicine and Neuromodulation amongst others.

pain cover.jpg

In 2010 I published a case of sustained reduction in blood pressure over 24 hours concomitant with pain relief with ventral PAG DBS on versus off, using ambulatory blood pressure monitoring.  That same year we published a detailed study using heart rate variability (an established measure of sympathetic tone) to characterise differences between ventral PAG’s more parasympathetic and dorsal PAG’s more sympathetic mechanisms of action in blood pressure control.

In 2011 Nik’s group published a case of reduction in blood pressure without pain relief in PAG DBS performed for chronic pain.  At the time I suggested in the news that

What their case report shows is that blood pressure can be reduced in a sustained fashion in a patient with unsuccessful deep brain stimulation for pain

In 2013 we published a large case series of DBS for pain suggesting that it is effective long-term in select aetiologies.  In 2014 I thoroughly reviewed the field of deep brain stimulation for chronic pain.  The patients receiving PAG DBS whose blood pressures had been studied were included in this cohort.

In 2013 we reported that the reduction in hypertension seen at one year in our patient receiving successful DBS for pain was not sustained at five years with presumed neurodegeneration.  This finding predicts the tolerance phenomenon seen in the current Bristol patient at two years after surgery.

Mr. Green continues to publish sophisticated research investigating the role of the human PAG in blood pressure control and sympathetic tone.  In 2016 we published a book together on the subject!

Bristol has precedent in performing first in man case reports of DBS building on decades of Oxford science.  Prof. Steve Gill’s pedunculopontine nucleus DBS for freezing and falling in Parkinson’s disease came about thanks to several years of rigorous animal research from Prof. Tipu Aziz, Prof. John Stein with their then doctoral student, and my now London Clinic consultant neurosurgeon colleague Mr. Dipankar Nandi.  The neurosurgeons in both cities have always been quick to acknowledge each other. Prof. Gill’s fellow, Mr. Puneet Plaha, who studied the patient even finished his training with me at Oxford and is now a successful brain tumour expert there.

Scientific progress is often fuelled by competition, conflict and rivalries and Sir Isaac Newton put it best.

Pigmaei gigantum humeris impositi plusquam ipsi gigantes vident

If I have seen further it is by standing on the shoulders of giants

It is rumoured that Newton meant this as a thinly veiled insult to his great rival Robert Hooke who was a man of diminutive stature.  Having studied at his alma mater and experienced first-hand the dry humour of its Fellows, I can well believe this.  Functional neurosurgery however exemplifies his observation in its romantic rather than its sarcastic form, so much so that a decade ago I began my published comprehensive history of stereotactic and functional neurosurgery in the UK ‘from Horsley to Hariz’ with his quote.  The Bristol and Oxford surgeons all acknowledge each other’s important contributions.  Their media officers perhaps lack such tradition and respect.  But then they probably don’t stand on giants’ shoulders.

In the mean time, please contact Mr Alex Green in Oxford or Mr Nik Patel in Bristol if you have a systolic blood pressure of over 300 and want deep brain stimulation.  While I am interested in related research into PAG DBS for the autonomic dysregulation of spinal cord injury, I am not brave enough to insert electrodes deep into the brains of patients with blood pressures that high!

St George’s deep brain stimulation service half a year on

Almost half a year on from starting the UK’s first new deep brain stimulation (DBS) neurosurgical service in half a decade, I am humbled by how our team has pulled together and flattered by the positive and gracious responses we have received from our first ten NHS patients so soon after the initial surgeries.

Two examples include:

I found Mr Pereira to be very open and honest as he explained the long process of DBS surgery to myself and my wife. He took his time, was relaxed and responded to all questions. He is extremely easy to talk to and his confident approach is very reassuring. We both felt inspired by him and knew I was in good hands. He came to see me immediately after the surgery in the recovery area. He calmly gave us an update of how the operation had gone and ensured we knew how to contact him and others if there were any issues during recovery and post-operatively. We’d like to thank him and the entire team involved in my surgery and stay at St George’s, it was an excellent experience.


Mr Pereira took on board all my concerns and acted on them although it made the surgery more complicated for him. He carried out the surgery without shaving any but the smallest patch of my very long hair and placed the battery at the top of my breast where it is invisible except with the lowest of necklines. Psychologically it helped so much. After fine tuning the stimulator I am feeling much better and can’t thank him and the St George’s team enough.

I can’t help but smile at the hyperbole of another patient:

Mr Pereira is quite simply the best of the best. Although his own brain must be the size of a small country and he has a talent given to very few people in the world, his ego is tiny and his compassion and humanity are great. DBS is not everyone’s idea of fun but he took time to explain it in the weeks before the operation in layman’s language, he was open and honest about the risks, and on the day itself he had an air of quiet authority which was immensely reassuring .And he was kind.

In my view, Mr. Pereira is a credit to neurosurgery, to the whole medical profession and to mankind.

There have been and continue to be challenges, difficulties and areas for improvement.  Nonetheless, achievements of the service to be proud of include that we have evolved slick and comfortable awake assessment during surgery and accurate electrode placement with no need for revisions and no infections so far in our early cohort.  We are implanting and programming deep brain stimulators from the three major manufacturers: Boston Scientific, Medtronic and Abbott / St Jude Medical.  We have appointed a superbly qualified service coordinator and expanded our clinical nurse specialist commitment.  Our expert academic neurologists have begun to gain support and salaries for their NHS commitments (which I hope will continue!) and we are starting to develop novel and exciting research projects around Parkinson’s disease, other movement disorders and neuromodulation in general.

All of this is a great excuse for our hard working team to share a celebratory cake!