Multidisciplinary consensus guideline for the diagnosis and management of spontaneous intracranial hypotension.

BACKGROUND: We aimed to create a multidisciplinary consensus clinical guideline for best practice in the diagnosis, investigation and management of spontaneous intracranial hypotension (SIH) due to cerebrospinal fluid leak based on current evidence and consensus from a multidisciplinary specialist interest group (SIG). METHODS: A 29-member SIG was established, with members from neurology, neuroradiology, anaesthetics, neurosurgery and patient representatives. The scope and purpose of the guideline were agreed by the SIG by consensus. The SIG then developed guideline statements for a series of question topics using a modified Delphi process. This process was supported by a systematic literature review, surveys of patients and healthcare professionals and review by several international experts on SIH. RESULTS: SIH and its differential diagnoses should be considered in any patient presenting with orthostatic headache. First-line imaging should be MRI of the brain with contrast and the whole spine. First-line treatment is non-targeted epidural blood patch (EBP), which should be performed as early as possible. We provide criteria for performing myelography depending on the spine MRI result and response to EBP, and we outline principles of treatments. Recommendations for conservative management, symptomatic treatment of headache and management of complications of SIH are also provided. CONCLUSIONS: This multidisciplinary consensus clinical guideline has the potential to increase awareness of SIH among healthcare professionals, produce greater consistency in care, improve diagnostic accuracy, promote effective investigations and treatments and reduce disability attributable to SIH.

Surgical decompressions for cauda equina syndrome during COVID-19.

BACKGROUND: The novel coronarvirus disease (COVID-19) has had a major impact on provision of spinal neurosurgery across the world, especially in the UK, with a significant fall in operating and patient volumes, and elective clinical activities. It is unclear whether the pandemic has affected the volume of urgent spinal procedures in the UK, especially surgical decompressions for cauda equina syndrome (CES). METHODS: Therefore, we conducted a retrospective analysis of theatre records and electronic operation notes at our institution to identify all procedures performed for CES before (December 2019 to February 2020) and during (March 2020 to May 2020) the COVID-19 pandemic. Statistical analyses were performed on SPSS v22 (IBM). RESULTS: Forty-four patients underwent surgical decompressions during the study period. Over half (54.5%) were female and the median age was 45 years (range = 22-78 years). Three in four procedures were performed at L4-5 and L5-S1 levels (79.5%). There was no statistically significant difference in the number of decompressions performed each month [χ2(5)=1.818; p = 0.874]. On the other hand, the number of referrals for suspected or confirmed CES fell by 81.8% between December 2019 and April 2020. CONCLUSIONS: Our results did not show any statistically significant decline in the volume of surgical decompressions performed for CES despite the considerable fall in electronic referrals for CES and degenerative spinal conditions. This suggests that patients with critical neurological symptoms continued to present and were treated appropriately despite the restrictions imposed on spinal surgeons during the pandemic.

Perioperative visual loss and consent for adult spine surgery: a national survey of the practice amongst spine surgeons and anaesthetists†.

BACKGROUND: Perioperative Visual Loss (POVL) is a devastating complication for patients undergoing spine surgery. Consent process for POVL amongst spine surgeons and anaesthetist remains variable. The aim of this study is to evaluate their practice and views about it. METHODS: Two similar questionnaires were distributed to members of the Society of British Neurological Surgeons (SBNS), British Association of Spine Surgeons (BASS), and Neuroanaesthsia and Critical Care Society (NACCS). RESULTS: A total of 271 responses were received (SBNS/BASS n = 149, NACCS n = 122). Fewer surgeons considered POVL as a material risk for patients compared to the anaesthetists (57.7 versus 79.7%). Outpatient/pre-assessment clinics were considered as the optimal setting for discussing POVL by the majority of the clinicians (81.2 and 93.4%). POVL should be discussed by both specialists according to 75% of the anaesthetists. Estimated incidence of POVL was considered to be higher by the anaesthetists (0.03-0.2% by 63% of the anaesthetist versus 0.0001-0.004% by 57% of the surgeons). Twenty-three surgeons and 10 anaesthetists had a patient who suffered from POVL, which led to a change of practice in most of them. This questionnaire will lead to a change in practice/consent to 18.1% of the surgeons and 23.5% of the anaesthetists. CONCLUSIONS: Most of the surgeons and anaesthetist feel that POVL is a material risk that ideally needs to be firstly discussed before the day of surgery, by both specialties. However, a significant number of clinicians have an opposite view. A national guidance from respective societies should encourage POVL to be discussed routinely.

Spinal cord compression due to nucleus migration from Mobi-C total disc replacement.

Cervical disc replacement is an alternative option to an anterior cervical discectomy and fusion for cervical spine degenerative disease. We present the first reported case of a progressively worsening symptomatic spinal cord compression secondary to migration of the nucleus from a Mobi-C total disc replacement.

Foramen magnum decompression for Chiari malformation type I - UK surgical practice.

Background: Symptomatic Chiari 1 malformation (CM1) is a common condition in Neurosurgery. Surgery involves hindbrain decompression and restoration of CSF flow through different surgical approaches. No Class 1 evidence exists to suggest the superiority of any of the surgical techniques.Aims: To investigate current surgical practice for symptomatic CM1 patients in the United Kingdom (UK) and determine the willingness to participate in a randomised controlled trial (RCT) comparing different surgical techniques.Methods: An electronic survey was sent to consultant members of the Society of British Neurological Surgeons and the British Chiari-Syringomyelia Group. The questions covered pre-operative and intra-operative management, presence of equipoise/uncertainty in optimal technique and willingness to participate in an RCT.Results: 98 responses were received. 67% operate on adults. 30% on adult and paediatric patients. There is variation in routine pre-operative use of: ICP monitoring (18%), flexion/extension x-rays (16%), venography (20%) and ophthalmology assessment (26%). 18% of neurosurgeons would not offer foramen magnum decompression when the presenting symptom is only refractory cough/sneeze headache. 15% routinely perform bony decompression alone in adults vs 8% in children. In 68% of adult cases, durotomy is performed routinely (46% of them leave the dura open, 54% perform a type of duroplasty) and 16% routinely resect the cerebellar tonsils. Only 17% leave the dura open in children. The most common indicators for durotomy are syringomyelia and intra-operative ultrasound findings. 61% believe there is equipoise/uncertainty in the optimal strategy for decompression and would be willing to participate in an RCT. Comments also mention the heterogeneity of CM1 and that treatment should be tailored to each patient.Conclusion: There is wide variation in pre- and intra-operative management of CM1 patients in the UK and the majority of neurosurgeons would be willing to participate in an RCT comparing bony decompression alone vs dural opening with/without duroplasty.

Potential wrong-level surgery for an intra-dural thoracic spinal tumour: the importance of optimum imaging and consistency in the direction in which the level is determined.

The spectre of wrong-level surgery has many a spinal surgeon double-checking the spinal level at which an operation is being carried out especially in the thoracic spine, in the absence of abnormal-looking vertebrae which could help to identify the intended level. Getting the level wrong is easily done if there is an unusual number of vertebrae or if the direction of the count digresses from the imaging available.

Cauda equina syndrome secondary to intradural renal cell carcinoma metastasis haemorrhage.

Intradural renal cell carcinoma (RCC) metastasis is rare. We report a case of an 81-year-old female presenting with acute cauda equina syndrome (CES), secondary to intradural RCC metastasis haemorrhage. To our knowledge this is the first case of CES secondary to acute haemorrhage within an intradural RCC metastasis.

Emergency neurosurgical referrals in the North East of England - trends over four years 2008-2011.

AIMS: On-call referrals are a considerable part of the neurosurgical workload. Many neurosurgical centres in the UK have now adopted the practice of maintenance of electronic databases to keep records of on-call activity. We analysed the neurosurgical on-call referrals database maintained at the Newcastle General Hospital (NGH)/Royal Victoria Infirmary (RVI) to assess any trends in the nature of referrals. METHODS: Retrospective review and statistical analysis of a contemporaneously populated referrals database, maintained at the Regional Neurosciences Unit in Newcastle. Data were analysed from August 2008 to April 2011. A three point moving average was used to depict trend in the number of referrals. Descriptive statistics were used to display other trends. Analysis was conducted using JMP 8.0.2 (SAS Institute, Cary, NC, USA). RESULTS: Our analysis reveals that the number of emergency referrals to neurosurgery in the North East of England is increasing year-on-year. Mean number of referrals per day has increased by almost 5 over the study period (9.06 in 2008 compared to 13.93 in 2011). The major diagnoses that account for this increase are lumbar degenerative conditions, intracerebral haematomas, spinal trauma and subarachnoid haemorrhage. 50% of the patients are referred out of hours and approximately one-third are admitted. In contrast, 47% of all referrals to rule out a cauda equina syndrome, need admission for scanning. General practitioners (GP) are the single biggest source of referral outside of the parent NHS trust and 47% of the GP referrals are regarding lumbar degenerative conditions and cauda equina syndrome. CONCLUSIONS: Continuously increasing referrals have implications on cost, staffing and sustainability of the service. Alternative referral pathways, especially for referrals from primary care, must be considered to restore the on-call workload to 'true' neurosurgical emergencies.

Foramen Magnum Decompression for Chiari Malformation Type 1: Is There a Superior Surgical Technique?

BACKGROUND: Foramen magnum decompression is a common operation used to treat Chiari malformation. There are different surgical techniques; however, some are anecdotally more effective than others. Our aim was to determine whether there is a superior technique in relation to revision rates, presence of persistent postoperative headache and nausea, and syrinx reduction. METHODS: This was a retrospective analysis of foramen magnum decompressions performed between 2012 and 2017 for Chiari 1 in a single institution. Three types of operations were performed: 1) bony decompression alone; 2) bony decompression with durotomy and dura left open; 3) bony decompression with opening of dura and duraplasty. We compared postoperative symptoms and revision rates between these 3 operations. RESULTS: In 168 patients, 185 foramen magnum decompressions were performed. Among the 168 primary operations, in 66 the dura was not opened, in 86 the dura was opened without a duraplasty, and in 16 a duraplasty was performed. Of 185 operations, 17 were revision surgery. For primary procedures, the revision rates were 12 (18%) where the dura was not opened, 4 (5%) where the dura was left open, and 1 (6%) when duraplasty was performed. Severe postoperative headache and nausea occurred in 2 (3%) patients where the dura was not opened, 4 (25%) patients after primary duraplasty, and 64 (74%) patients after primary durotomy. CONCLUSIONS: In this study, rate of revision surgery was highest in patients who had bony decompression without dural opening. Rate of postoperative headache and nausea was highest in the durotomy group. Overall duraplasty had the best results.

Survey of healthcare professionals' knowledge, attitudes and practices regarding spontaneous intracranial hypotension.

Objective: To assess the knowledge, attitudes and practices of healthcare professionals regarding the diagnosis and management of spontaneous intracranial hypotension (SIH). Methods: We performed a cross-sectional, web-based survey of multiple healthcare professional groups in the UK from June to August 2021. There were 227 respondents to the survey, including 62 general practitioners, 39 emergency medicine physicians, 38 neurologists, 35 radiologists, 20 neurosurgeons, 18 anaesthetists and 15 headache nurse specialists. The majority of the respondents were at the consultant level and all worked in the UK National Health Service. Results: Few general practitioners or emergency medicine physicians had ever been involved in the care of a patient with SIH or received teaching about SIH. Only 3 of 62 (4.8%) general practitioners and 1 of 39 (2.5%) emergency medicine physicians were confident in recognising the symptoms of SIH. Most neurologists were confident in recognising SIH and performed MRI of the brain as a first-line investigation, although there was variability in the urgency of the request, whether contrast was given or MRI of the spine organised at the same time. Most said they never or rarely performed lumbar puncture for diagnosis of SIH. Most neuroradiologists, but few general radiologists, were confident in interpreting imaging of patients with suspected SIH. Lack of access to epidural blood patching, personnel able to perform myelography, and established management pathways were identified by many respondents as barriers to the treatment of SIH. Conclusions: We have identified a lack of awareness of SIH among non-specialists, several barriers to optimal treatment of SIH and a variation in current management pathways. The results highlight the need for education of healthcare professionals about SIH and the development of clinical practice guidelines to enable delivery of optimal and equitable care for patients with SIH.

Retrieval analysis of an explanted Mobi-C cervical disc replacement: A case study.

Ex vivo analysis of artificial discs is essential to better understand their ability to replace degenerated intervertebral discs. The Mobi-C differs from some other contemporary disc designs in that it has a mobile polyethylene insert that is sandwiched between superior and inferior cobalt chromium endplates. While some studies claim the Mobi-C to have restored normal cervical spinal biomechanics, others have noted high levels of migration. Our objective was to contribute to this debate by, for the first time, analysing an explanted Mobi-C cervical disc which was removed due to worsening myelopathy at the nano and macro scales. Intraoperatively, the insert was found to have excessively migrated and it compressed the spinal cord. Roughness was measured as 0.016 ± 0.006 µm (Sa) and 0.055 ± 0.020 µm (Sa) for the superior and inferior plates, and 1.210 ± 0.154 µm (Sa) and 0.446 ± 0.083 µm (Sa) for the superior and inferior surfaces of the insert. Compared to unworn surfaces, the roughness increased for the superior and inferior plates and decreased for both surfaces of the insert. However, the only statistically significant change occurred on the articulating surface of the inferior plate (p = 0.04). At the nanoscale, valleys dominated the articulating surfaces. The superior plate had a burnished appearance whereas the inferior plate appeared matt. Impingement was observed on the endplates. The insert was severely damaged, burnished and had scratches. Additionally, subsurface whitening and internal cracking were observed on the insert.