20th September 2019, The National Hospital of Neurology and Neurosurgery, London
This article was kindly submitted by Clare Joy, a Trustee of the CSF Leak Association, who was able to attend the Study Day.
The study day only became a reality because of the work behind the scenes by the charity’s Medical Advisory Committee and in particular, its chair, Dr Manjit Matharu. The Board of Trustees would like to express its sincere gratitude to all the speakers and attendees. It was truly a fantastic day for sharing of current practice in the UK, learning from published literature on practices from further afield, discussing what could be best practice and learning how much we don’t know yet. It was humbling realising the mammoth task ahead of us in producing a consensus statement and guidelines. The day was attended by thirty healthcare professionals (neurologists, neurosurgeons, neuroradiologists, anaesthetists, nurses) and five ‘expert patients’ - trustees Clare Joy and Tamsin Trevarthen and volunteers Russell Secker, Sandie Moore and Dr Jenny Pople.
Session 1 - Overview & Diagnosis
1. Systematic review on Spontaneous Intracranial Hypotension, Dr Manjit Matharu
Dr Matharu presented the preliminary results of a systemic review of all English language published literature on Spontaneous Intracranial Hypotension (SIH) found using specific key words. He credited Dr Linda D’Antona for doing most of the work involved in identifying studies for inclusion in the review and for aggregating the results across multiple studies to present in this presentation. The review was comprehensive and touched on a multitude of aspects of SIH but from a patient perspective it was telling that there were no studies on the impact on patients’ quality of life. Aspects touched on included the type of headache on initial presentation to neurology, pressure measured by lumbar puncture, the findings of brain and spinal imaging, location of leak, outcomes for conservative treatment (bed rest), outcomes for patching and surgery. There was discussion throughout when a result presented did not match the speaker or audience’s experience, e.g. high success rates for first blood patch. It is hoped that this work will be published soon and the message is clear, more research with better datasets is required.
2. Orthostatic headache - working through the differential diagnosis, Dr Callum Duncan
Dr Duncan presented some other diagnoses to consider when there is a suspicion of the leak. He said the main differential is Postural orthostatic Tachycardia Syndrome (PoTS) which may present with worsening headache when upright with tachycardia. He explained how the most common differential is chronic migraine – a patient experiencing a migraine will want to lie down but that this is most likely due to motion sensitivity and the patient will feel better lying still and not moving.
3. Are the diagnostic criteria for SIH fit for purpose? Dr Simon Ellis
Dr Simon Ellis outlined the evolution of the diagnostic criteria for SIH from the 2004 International Classification of Headache Disorders 2nd edition (ICHD-2, section 7.2.3) to the ICHD-3 in 2018 and touched on particular papers where authors had proposed changes to the criteria or where published results were of interest, e.g. Schievink 2011 (criteria proposed - click here to read the associated paper), Kranz 2016 (imaging is not conclusive), Tanaka 2016 (age and sex differences in presentation - click here to read the associated paper) and Graf 2018 (can’t distinguish between SIH and PoTS; click here to read the associated paper). Discussion included how problematic the diagnostic criteria are because they make reference to low CSF pressure and positive image findings but we know that normal pressure and normal imaging can be found in a patient with a leak. There is the additional diagnostic hurdle that some patients can have more than one headache type at play
Session 2 - Investigations
1. Lumbar puncture: is it a useful investigation? Dr Jane Anderson
This was quite an interactive presentation where the audience shared their practice on whether or not a lumbar puncture to measure the CSF pressure should be done and if it was normal would that rule out a leak. Many felt that it should not be done as a stand alone test in classic presentations but that it is often used to rule out other conditions/diseases when the diagnosis is not clear. Many also stated that opening pressure should be done at the time of a myelogram (if sending the patient for a myelogram).
2. Overview of the Neuroimaging Techniques: which technique and when? Dr Indran Davagnanam
Dr Davagnanam spoke about the different types of imaging that could be used in determining the presence of a leak and for determining the leaks location. He acknowledged that clear imaging does not rule out a leak. Discussion in the Q&A touched on radiologist training in spotting the sometimes subtle signs of a leak, particular methods for performing dynamic CT myelography, the use of gadolinium contrast in MR imaging and what kind of images the audience would request.
3. What is the role of Intracranial Pressure (ICP) monitoring? Mr Ahmed Toma
Mr Toma described the different technologies for measuring ICP and went on to explain that the work with ICP monitoring in Queen Square pertained to the changes in ‘median ICP’ and ‘pulse amplitude’ in patients with hydrocephalus and CSF disorders (click here to read the associated paper) and how the team there hopes to publish more in the future. So far they’ve found that roughly one third of patients undergoing ICP monitoring for query CSF leak are found to have low pressure with another third having normal pressure and the final third found to have high pressure.
Session 3 - Management
1. Conservative management and drug treatments, Dr Paul Dorman
Dr Dorman explained how conservative management (bed rest) is not routinely prescribed in Newcastle due to the delay in seeing patients meaning that most patients have already tried bed rest. Little is known about how many spontaneous leaks resolve with bed rest compared to iatrogenic leaks, e.g. lumbar punctures. When discussing drug treatments the Cochrane systematic review on post dural puncture headache was discussed (click here to read the associated paper) where there was some evidence for caffeine, gabapentin, theophylline and hydrocortisone. The discussion amongst the audience was that many centres do not routinely offer caffeine infusions anymore because patients still ended up needing a blood patch.
2. Epidural blood patches, Dr Anthony Ordman
Dr Ordman detailed his procedure for consenting, administering and follow up of blood patches. He expressed his belief that not only is it important to explain the benefits and risks of a patch, as with any medical procedure, but also to explain what to expect, how symptoms may change and when to consider another patch. The audience discussed the theory that the course of symptoms after a patch was bimodal – early relief (sometimes total, may be short lived) followed by a lull and then after a few weeks a more gradual improvement. The underlying mechanism remains a mystery.
3. Evidence base for surgery in management of SIH, Mr James Walkden
Mr Walkden treated us to a whirlwind tour of the literature. He touched cranial leaks - patients with anterior fossa leaks (nasal) tend not to have SIH whereas those with middle fossa (ear) do. He stressed that surgery for cranial or spinal leaks depended on good imaging studies for locating the leak site but also to determine the vasculature supplying the nearby nerves to reduce complications. He talked us through some fascinating short videos of surgeries he had recorded while trying to hunt down and seal a defect in the dura.
4. Management pathways at:
- Glasgow, Dr Alok Tyagi
- University Hospital of the North Midlands, Dr Simon Ellis
- Newcastle, Dr Paul Dorman
- The National Hospital for Neurology and Neurosurgery, Dr Manjit Matharu
By this time of the day we were well behind the programme due to the amount of worthwhile discussion happening at the end of each presentation. This final presentation was quite brief where each of the speakers shared what the pathway was at their centre. There was some discussion on how rigid or otherwise each centre’s pathway was and much discussion on the need for a guideline document. From a patient perspective it became evident to me that all the healthcare professionals in the room agreed on one thing – that multidisciplinary team working was at the core of their service and that any plans for the future would have to work for all disciplines and need their buy in.
Session 4 - Guideline development
Finally we reached the last session with very little time left but as it happened a lot of the questions planned to be raised in this session were discussed throughout the day. The majority of the audience agreed that a guideline or consensus statement was the best way forward with the aim of reducing diagnostic delays and time to intervention (e.g. patching). The exact format and nature of the process and the personnel required are yet to be bottomed out but it soon became clear that funding is our next big hurdle. The process is likely to be long and involve multiple meetings and possibly require pertinent clinical questions (take your pick from above!) to be answered via research before a consensus can be achieved.
In conclusion – a thought provoking and hopeful day made even more so by a fantastic leaker meet up and the engagement of interested healthcare professionals who really do care about our small (but vocal) community. I am both humbled by their compassion and slightly dumbstruck by the sheer size of the task ahead of us especially when it feels like the NHS is working beyond capacity already.