Patient-specific automated cerebrospinal fluid pressure control to augment spinal wound closure: a case series using the LiquoGuard®.

OBJECTIVE: Spinal cerebrospinal fluid (CSF) leaks are common, and their management is heterogeneous. For high-flow leaks, numerous studies advocate for primary dural repair and CSF diversion. The LiquoGuard7® allows automated and precise pressure and volume control, and calculation of patient-specific CSF production rate (prCSF), which is hypothesized to be increased in the context of durotomies and CSF leaks. METHODS: This single-centre illustrative case series included patients undergoing complex spinal surgery where: 1) a high flow intra-operative and/or post-operative CSF leak was expected and 2) lumbar CSF drainage was performed using a LiquoGuard7®. CSF diversion was tailored to prCSF for each patient, combined with layered spinal wound closure. RESULTS: Three patients were included, with a variety of pathologies: T7/T8 disc prolapse, T8-T9 meningioma, and T4-T5 metastatic spinal cord compression. The first two patients underwent CSF diversion to prevent post-op CSF leak, whilst the third required this in response to post-op CSF leak. CSF hyperproduction was evident in all cases (mean >/=140ml/hr). With patient-specific CSF diversion regimes, no cases required further intervention for CSF fistulae repair (including for pleural CSF effusion), wound breakdown or infection. CONCLUSIONS: Patient-specific cerebrospinal fluid drainage may be a useful tool in the management of high-flow intra-operative and post-operative CSF leaks during complex spinal surgery. These systems may reduce post-operative CSF leakage from the wound or into adjacent body cavities. Further larger studies are needed to evaluate the comparative benefits and cost-effectiveness of this approach.

Drop metastasis from the extradural to the intradural space in spinal Ewing's sarcoma - a novel case report.

Spinal Ewing's Sarcoma is a rare tumour predominantly affecting children and adolescents. We describe the case of an 18-year-old male patient who first presented with a primary extradural cervical Ewing's sarcoma tumour, and 5 years later had a recurrence with thoracolumbar and lumbosacral intradural extramedullary Ewing's sarcoma tumours. Both presentations were successfully treated by surgical resection and adjuvant chemo- and radiotherapy, and he remains disease-free at 12 months follow-up. This is the first reported case of seeding of tumour from an extradural primary Ewing's sarcoma to intradural metastases. Total surgical resection of his initial cervical tumour, performed at another centre, was complicated by a dural tear and CSF leak. Thus, we propose that isolated drop metastasis via CSF fistula is the most likely mechanism for tumour spread in this case. Thus, clinicians may wish to counsel patients on the possibility of such spread if a CSF leak is encountered, and potentially increase the frequency of imaging surveillance of the whole spine in this context.

The Relative Merits of Posterior Surgical Treatments for Multi-Level Degenerative Cervical Myelopathy Remain Uncertain: Findings from a Systematic Review.

OBJECTIVES: To assess the reporting of study design and characteristics in multi-level degenerative cervical myelopathy (DCM) treated by posterior surgical approaches, and perform a comparison of clinical and radiographic outcomes between different approaches. METHODS: A literature search was performed in Embase and MEDLINE between 1995-2019 using a sensitive search string combination. Studies were selected by predefined selection criteria: Full text articles in English, with >10 patients (prospective) or >50 patients (retrospective), reporting outcomes of multi-level DCM treated by posterior surgical approach. RESULTS: A total of 75 studies involving 19,510 patients, conducted worldwide, were identified. Laminoplasty was described in 56 studies (75%), followed by laminectomy with (36%) and without fusion (16%). The majority of studies were conducted in Asia (84%), in the period of 2016-2019 (51%), of which laminoplasty was studied predominantly. Twelve (16%) prospective studies and 63 (84%) retrospective studies were identified. The vast majority of studies were conducted in a single centre (95%) with clear inclusion/exclusion criteria and explicit cause of DCM. Eleven studies (15%) included patients with ossification of the posterior longitudinal ligament exclusively with cohorts of 57 to 252. The clinical and radiographic outcomes were reported with heterogeneity when comparing laminoplasty, laminectomy with and without fusion. CONCLUSIONS: Heterogeneity in the reporting of study and sample characteristics exists, as well as in clinical and radiographic outcomes, with a paucity of studies with a higher level of evidence. Future studies are needed to elucidate the clinical effectiveness of posterior surgical treatments.

UK Chiari 1 Study: protocol for a prospective, observational, multicentre study.

INTRODUCTION: Chiari 1 malformation (CM1) is a structural abnormality of the hindbrain characterised by the descent of the cerebellar tonsils through the foramen magnum. The management of patients with CM1 remains contentious since there are currently no UK or international guidelines for clinicians. We therefore propose a collaborative, prospective, multicentre study on the investigation, management and outcome of CM1 in the UK: the UK Chiari 1 Study (UKC1S). Our primary objective is to determine the health-related quality of life (HRQoL) in patients with a new diagnosis of CM1 managed either conservatively or surgically at 12 months of follow-up. We also aim to: (A) determine HRQoL 12 months following surgery; (B) measure complications 12 months following surgery; (C) determine the natural history of patients with CM1 treated conservatively without surgery; (D) determine the radiological correlates of presenting symptoms, signs and outcomes; and (E) determine the scope and variation within UK practice in referral patterns, patient pathways, investigations and surgical decisions. METHODS AND ANALYSIS: The UKC1S will be a prospective, multicentre and observational study that will follow the British Neurosurgical Trainee Research Collaborative model of collaborative research. Patients will be recruited after attending their first neurosurgical outpatient clinic appointment. Follow-up data will be collected from all patients at 12 months from baseline regardless of whether they are treated surgically or not. A further 12-month postoperative follow-up timepoint will be added for patients treated with decompressive surgery. The study is expected to last three years. ETHICS AND DISSEMINATION: The UKC1S received a favourable ethical opinion from the East Midlands Leicester South Research Ethics Committee (REC reference: 20/EM/0053; IRAS 269739) and the Health Research Authority. The results of the study will be published in peer-reviewed medical journals, presented at scientific conferences, shared with collaborating sites and shared with participant patients if they so wish.

Failed Foramen Magnum Decompression in Chiari I Malformation Is Associated With Failure to Restore Normal Intracranial Compliance: An Observational Cohort Study.

BACKGROUND: The standard treatment for symptomatic Chiari malformation (CM) I is foramen magnum decompression (FMD) to facilitate cerebral spinal fluid flow through the foramen magnum, improve intracranial compliance, and alleviate symptoms (commonly headache). This procedure has a variable success rate, with a significant proportion of patients having persistent symptoms after surgery. OBJECTIVE: To investigate intracranial pressure (ICP) hydrodynamics in symptomatic surgery-naïve patients with CM I and symptomatic patients who have had prior FMD. METHODS: We undertook a retrospective, observational cohort study, extracting data from our departmental ICP database. Patients with untreated ("Virgin") Chiari malformations (VCM), patients with previous "failed" FMD (ie, with persistent classical Chiari symptoms) (fFMD) and a normal control group, all with existing continuous ICP monitoring date were included. Median ICP (mICP) and median pulse amplitude (mPA) were compared between the groups. RESULTS: A total of 33 CM patients (22 VCM and 11 fFMD) and 42 normal controls were included for analysis. mICP did not differ significantly between the normal control, VCM, and fFMD groups. mPA in the VCM and fFMD groups was significantly higher than the control group (P < .01 and P < .05, respectively). CONCLUSION: In this cohort, patients with persistent symptoms after FMD have persistently impaired intracranial compliance, similar to patients who have not undergone surgery at all when compared with a control group. The reasons for this are not clear, and further research is required to establish the causation and optimum management for failed FMD.

Neuro-critical care: a valuable placement during foundation and early neurosurgical training.

INTRODUCTION: Neurosciences critical care units (NCCUs) present a unique opportunity to junior trainees in neurosurgery as well as foundation trainees looking to gain experience in the management of critically ill patients with neurological conditions. Placements in NCCUs are undertaken in the early years of neurosurgical training or during neurosciences themed foundation programmes. We sought to quantify the educational benefits of such placements from the trainee perspective. METHODS: Thirty-two trainees who had undertaken placements at Foundation Year 2 (FY2) to Specialty Trainee Year 3 (ST3) level between August 2009 and April 2013 were invited to take part in an online questionnaire survey. Competence in individual skills was self-rated on a ranked scale from one (never observed) to five (performed unsupervised) both before and after the placement. Trainees were also asked a series of questions pertaining to their ability to manage common neurosurgical conditions, as well as the perceived educational rigour of their placement. RESULTS: Twenty-three responses were received. Eighteen responses were from FY2s and seven were from ST1-3 level trainees. Following their placements, 100% of respondents felt better equipped to deal with neurosurgical and neurological emergencies and cranial trauma. Most felt better equipped to manage hydrocephalus (95.7%), polytrauma patients (95.7%), spontaneous intracranial haemorrhage (91.3%) and spinal trauma (82.6%). Significant increases were seen in experience in all practical skills assessed. These included central venous catheterisation (p < 0.001), intracranial pressure (ICP) bolt insertion (p < 0.001), ICP bolt removal (p < 0.001), external ventricular drain (EVD) insertion (p = 0.001) and tapping of EVD for cerebrospinal fluid sample (p < 0.001). CONCLUSION: Our results clearly demonstrate the educational benefits of NCCU placements in the early stages of a neurosurgical training programme as well as in the Foundation Programme. This supports the incorporation of a four- to six-month NCCU rotation in early years training as educationally valuable.