Dorsal root entry zone lesioning for brachial plexus avulsion - technical evolution and long-term follow-up.

BACKGROUND: Brachial plexus avulsion (BPA) injuries can cause severe deafferentation pain. This has been successfully treated with dorsal root entry zone (DREZ) lesioning. Distortions in anatomy following a BPA injury can make identifying neural structures challenging. We describe a modification to the operative technique that improves the surgical view and the advanced intraoperative neuromonitoring (IONM) employed to identify DREZ. We have analysed the long-term outcomes for pain, quality of life, and complications in patients undergoing DREZ lesioning. METHODS: This is a single-centre retrospective case series including patients who underwent DREZ lesioning with IONM for brachial plexus avulsion between 2012 and 2022. Analysed data included pre- and postoperative pain (VAS), quality of life score for chronic pain, and complications. The evolution of the surgical approach is discussed. RESULTS: 44 consecutive patients underwent a DREZ lesioning procedure with intraoperative monitoring and mapping. In these patients the mean VAS score improved from 8.9 (7-10) to 1.87 (0-6) (p < 0.0001) at the time of discharge. 31 patients were followed-up for more than 12 months with a mean duration of follow-up of 41 months and their results were as follows: the mean VAS improved from 9.0 (7-10) to 4.1 (0-9) (p < 0.0001) at the last follow-up and the mean QOL values improved from 3.7 (2-6) to 7.4 (4-10) (p < 0.0001). The long-term outcomes were 'good' in 39%, 'fair' in 29% and 'poor' in 32% of patients. 55% of the patients were able to stop or reduce pain medications. CONCLUSIONS: Modifications of surgical technique provide better exposure of DREZ, and IONM aids in identifying DREZ in the presence of severe intra-dural changes. Long-term outcomes of DREZ lesioning indicate not only a reduction in pain but also a significant improvement in quality of life.

Trigeminal neuropathy presenting secondary to SARS-CoV-2 infection.

Introduction: A 58-year-old woman presented to a multidisciplinary facial pain clinic in October 2021 complaining of a constant pain in the right side of her face since contracting coronavirus SARS-CoV-2 18 months earlier. The pain extending from the right temple down to her right cheek extraorally and including the maxillary teeth and right side of tongue intraorally. This was accompanied by anosmia, diplopia on lateral gaze, and dizziness. Methods: Clinical examination was supplemented with several neurophysiological tests to confirm the diagnosis including an MRI brain scan, quantitative sensory testing, electrophysiological blink reflex testing, corneal confocal microscopy, and pain and short-form anxiety and depression questionnaires. Results: Quantitative sensory testing showed unilateral loss of perception in thermal and mechanical sensibility and bilateral hyperalgesia indicating central sensitization. Bilateral corneal confocal microscopy showed an abnormally reduced corneal nerve fibre length on the right side. MRI, blink reflex, and masseter inhibitory testing findings were normal. Conclusion: This case study is the first case of trigeminal neuropathy related to SARS-CoV-2 infection reported in the literature. It also discusses the successful management of the patient's trigeminal neuropathic pain.

Open Thoracic Cordotomy for Cancer Pain with Intraoperative Neuromonitoring: A Case Series and Critical Review of the Literature.

OBJECTIVE: Cordotomy is a viable option for patients with intractable cancer pain and limited survival. Open thoracic cordotomy is offered when patients are not candidates for percutaneous cordotomy. After the open procedure, traditionally performed purely based on anatomic landmarks, up to 22% of patients experience postoperative limb weakness. The objective of this study is to report our experience with neurophysiology-guided open cordotomy along with a critical review of the literature. METHODS: Between 2019 and 2022, 5 open thoracic cordotomies were performed in our center. Intraoperative neurophysiologic monitoring was used in all cases to guide the lesion and standard single-level laminectomy or hemilaminectomy was performed for exposure. Outcome measures were retrospectively reviewed focusing on pain control and neurologic status. Existing literature on cordotomy was critically reviewed. RESULTS: There was satisfactory pain relief with preservation of motor function in all 5 cases. Temperature sensation was preserved in all but 1 patient, who lost it after the previous ipsilateral percutaneous cordotomy (PCC). No procedural complications were experienced. We found that the neurophysiology monitoring lesion was guided anterior compared with what would have been lesioned on an anatomic basis. CONCLUSIONS: Open thoracic cordotomy is a safe and effective procedure for intractable cancer-related pain. Technical advancements significantly reduced mortality and major morbidity of PCC. Our series suggests that neurophysiology monitoring alters the location of the lesion and may help better targeting of pain fibers within the spinothalamic tract and preserve other long tracts. The safety profile of open cordotomy with neurophysiology compares favorably with the PCC.

Real world experience with minimally invasive wireless percutaneous neuromodulation in a tertiary care centre.

Background: Wireless percutaneous nerve stimulation (PNS) for chronic pain is rapidly evolving in the ever expanding neuromodulation paradigm. Safety and lower risks with a potential of long-term analgesia cannot be over emphasised especially with the ongoing opioid pandemic. PNS with an implanted pulse generator (IPG) has also been shown to provide good benefit, without often unpleasant widespread paraesthesia from conventional spinal cord stimulators. Aim and Methods: We retrospectively extracted data on all wireless PNS implants in our highly specialised pain neuromodulation centre since initiation of wireless PNS service in August 2019. Patient demographics, pain history, analgesic intake and details on implant follow-up data within 1 year post-implant including pain relief, EuroQol-5 Dimension (EQ-5D) and Patients' Global Impression of Change (PGIC) scores were extracted. The cases are presented in a narrative format. Result: A total of five patients were implanted with wireless (Stimwave®) PNS from August 2019 to February 2020. Neuropathic pain was the most common presenting diagnosis. All patients showed >50% pain relief at 3 months. EQ-5D and PGIC did not show any improvement in the subjects. Two of the patients managed to decrease their analgesics after implantation. Similar sustained benefits could not be demonstrated after 1 year. Discussion: PNS can provide analgesia in appropriately selected cases. Naivety of the technique and procedure might cause some degree of uncertainty. External pulse generator with wireless transmission avoids IPG and tunnelling related side effects, but requires individualised special wearable technology to power the lead. Minimally invasive nature of the technique might be attractive and preferable for patients with complex medical issues, nickel allergy and poor general health who may otherwise be unsuitable for Spinal Cord Stimulation (SCS) with conventional hardware. Robust prospective controlled studies and RCTs in future might provide further insights on utility in other neuropathic pain diagnosis, long-term outcomes and acceptability compared to conventional SCS.

Could ZI have a role in DBS for Parkinson's Disease? An observational study to optimize DBS target localization.

Deep Brain Stimulation (DBS) of the subthalamic nucleus (STN) is a well-recognized intervention for Parkinson's Disease (PD). We used LEAD-DBS, a toolbox facilitating DBS electrode reconstructions and computer simulations based on postoperative MRI and CT imaging, to investigate the interaction and followed benefits of electrical field generated by STN-DBS and surrounding areas, such as caudal Zona Incerta (cZI). Thirty-two PD patients, treated with directional STN-DBS in the period 2016-2018 at the Walton Center NHS Foundation Trust, were retrospectively recruited. Their MRI and CT imaging were analyzed with LEAD-DBS to measure the volume of tissue activated (VTA). Considering the clinical outcome based on the UPDRS III score improvement of 62.65% at 6 months follow up, we found a VTA intersection of 21.5% with motor STN and 61.7% with cZI. These observations may support the contribution of cZI deep stimulation to improve clinical outcome of PD patients treated with DBS, promoting the intriguing path of dual targeting.

Compartmentalisation of the inflammatory response following aneurysmal subarachnoid haemorrhage.

INTRODUCTION: There is some evidence to suggest that a systemic and central nervous system (CNS) inflammatory response occurs following aneurysmal subarachnoid haemorrhage (aSAH) which may be related to the pathophysiology of early brain injury and delayed ischaemic neurological deficit (DIND). The aim of this study was to measure inflammatory mediator levels in plasma and cerebrospinal fluid (CSF) in the days following aSAH and to determine their association with aSAH, DIND and clinical outcome. MATERIAL AND METHODS: Plasma and CSF samples were obtained prospectively from patients with aSAH on days 1-3, 5, 7 and 9 and profiled for interleukin (IL)-1α, IL-1ß, IL-4, IL-6, IL-8, IL-10, IL-15, IL-17, IL-18, macrophage chemotactic protein (MCP)-1, vascular endothelial growth factor (VEGF) and tumour necrosis factor (TNF)-α. Plasma and CSF samples from non-aSAH patients undergoing spinal anaesthesia were used as controls. RESULTS: The CSF levels of all cytokines investigated except for IL-1α were significantly higher in aSAH compared to controls in the first seven days of ictus. CSF levels of IL-1α (p = 0.014), IL-18 (p = 0.016), IL-6 (p = 0.0006) and IL-8 (p = 0.006) showed significant increases in the days following aSAH. Conversely IL-17 demonstrated a decrease. In particular, IL-4 was higher in the CSF of patients who had DIND at all time-points (p = 0.032). Plasma IL-6 and IL-8 levels were higher, and IL-1α levels lower, than controls at most time-points. All mediators demonstrated persistent elevation in the CSF compared to plasma apart from IL-1α and IL-18 which followed the opposite trend. Day 3 plasma IL-6 levels predicted poor outcome at six months (Exp(B) 1.12 1.03-1.22, P = 0.012), although this association was lost in the second analysis incorporating Fisher grade, WFNS grade and age. CONCLUSION: The post aSAH inflammatory response peaks on days 5-7 post ictus and remains largely compartmentalised within the CNS. IL-4 may have a particular association with DIND although its precise role in the pathophysiology of the disorder remains unclear. IL-6 predicted poor outcome but not independently of clinical grade, suggesting that it may be a surrogate marker of early brain injury.

Frontal skull osteoblastoma with aneurysmal bone cyst-like changes associated with trauma during pregnancy: a case report.

We report the case of a large osteoblastoma arising in the frontal bone of a 20-year-old female. The lesion was first noted after a fall, and grew steadily in size following further head injury during pregnancy. Initial plain radiography demonstrated an area of radiolucency, with subsequent cross-sectional imaging revealing the extent of the lesion. Following successful surgical resection, histological features were suggestive of an aggressive osteoblastoma with aneurysmal bone cyst-like changes. We consider the influence of pregnancy and trauma on osteoblastoma behavior.

Self-perceived health status following aneurysmal subarachnoid haemorrhage: a cohort study.

OBJECTIVE: The objective of the study was to assess the long-term self-reported health status and quality of life (QoL) of patients following an aneurysmal subarachnoid haemorrhage (ASAH) using a self-completed questionnaire booklet. DESIGN: A two-cohort study. SETTING: A regional tertiary neurosurgical centre. PARTICIPANTS: 2 cohorts of patients with ASAH treated between 1998 and 2008 and followed up at approximately 1 year. INTERVENTIONS: Routine care. PRIMARY AND SECONDARY OUTCOMES: A range of standardised scales included: AKC Short Sentences Test, the Barthel Index, the Self-Report Dysexecutive Questionnaire, the Everyday Memory Questionnaire, Stroke Symptom Checklist, Wimbledon Self-Report Scale, Modified Rankin Score (MRS) and a new Stroke-QoL. The data from summated scales were fit to the Rasch measurement model to validate the summed score. RESULTS: 214 patients (48%) returned the questionnaires; the majority (76%) had a World Federation of Neurosurgeons grade of 1 or 2. The most frequent aneurysm type was that of the anterior communicating artery (28%) with approximately 90% of aneurysms of the anterior circulation. Of those previously in full or part-time employment, 48.9% were unemployed at follow-up. All summated scales satisfied the Rasch measurement model requirements, such that their summed scores were a sufficient statistic. Given this, one-third of patients were noted to have a significant mood disorder and 25% had significant dysexecutive function. Patients with an MRS of 3, 4 or 5 had significantly worse scores on most outcome measures, but a significant minority of those with a score of zero had failed to return to work and displayed significant mood disorder. CONCLUSIONS: A range of self-reported cognitive and physical deficits have been highlighted in a cohort of patients with ASAH. While the MRS has been shown to provide a reasonable indication of outcome, in routine clinical follow-up it requires supplementation by instruments assessing dysexecutive function, memory and mood.

Mitigating effects of external ventricular drain usage in the management of severe head injury.

BACKGROUND: Cerebrospinal fluid (CSF) drainage has been variably employed to lower intracranial pressure (ICP) in patients with severe head injury. The efficacy of this manoeuvre remains under-explored (Brain Trauma Foundation Recommendation-optional treatment). This work seeks to report the results of CSF drainage via external ventricular drain (EVD) in severe head injury in comparison to other treatment options. METHODS: Retrospective observational comparative study of all consecutive patients admitted to a major trauma centre with severe traumatic brain injury over a period of 12 months. RESULTS: Out of a total 139 patients, 33 had delayed elevation of ICP despite conventional medical therapy, 16 patients were treated with EVD insertion (4 placed under AxiEM image guidance [Medtronic]) and 17 received either decompressive craniectomy or barbiturate coma. Subsequently, two patients with decompression had further ICP elevation and needed EVD. Two patients with EVD had raised ICP-one underwent decompression and the other was treated with barbiturate coma. One patient with EVD developed infection, which was successfully treated. Patients treated with EVD had a lower risk of needing definitive treatment for ICP control, i.e. decompressive craniectomy or barbiturate coma. CONCLUSIONS: EVD was a safe and less invasive procedure, and achieved sustained control of ICP in this patient group.

Identifying patient report outcomes relevant to aneurysmal subarachnoid hemorrhage follow-up.

Patients recovered from subarachnoid hemorrhage can be assessed for neuropsychological dysfunction using postal questionnaires. We assessed 214 patients using various tests of memory, mood and strategic thinking. Patients in good outcome categories (modified Rankin Scale [mRS] 0-1) nevertheless exhibited mood disorder (28%), memory deficit and executive dysfunction (20%). Return to work (49%) was most influenced by previous employment status, Rankin scale and mood.

Lumbar drainage of cerebrospinal fluid after aneurysmal subarachnoid hemorrhage: a prospective, randomized, controlled trial (LUMAS).

BACKGROUND AND PURPOSE: A single-center prospective randomized controlled trial has been conducted to determine if lumbar drainage of cerebrospinal fluid after aneurysmal subarachnoid hemorrhage reduces the prevalence of delayed ischemic neurological deficit and improves clinical outcome. METHODS: Patients with World Federation of Neurological Surgeons Grade 1 to 3 aneurysmal subarachnoid hemorrhage and modified Fisher Grades 2, 3, 4, and 3+4 were randomized to either the study group of standard therapy plus insertion of a lumbar drain or the control group of standard therapy alone. The primary outcome measure was the prevalence of delayed ischemic neurological deficit. RESULTS: Two hundred ten patients with aneurysmal subarachnoid hemorrhage (166 female, 44 male; median age, 54 years; interquartile range, 45-62 years) were recruited into the control (n=105) and study (n=105) groups of the trial. World Federation of Neurological Surgeons grade was: 1 (n=139), 2 (n=60), and 3 (n=11); Fisher grade was: 2 (n=87), 3 (n=85), and 4 (n=38). The prevalence of delayed ischemic neurological deficit was 35.2% and 21.0% in the control and study groups, respectively (P=0.021). The prevalence of a modified Rankin Scale score of 4, 5, or 6 at Day 10 and 6 months, respectively, was 62.5% and 18.6% in the control group and 44.8% and 19.8% in the study group (P=0.009 and 0.83, respectively). CONCLUSIONS: Lumbar drainage of cerebrospinal fluid after aneurysmal subarachnoid hemorrhage has been shown to reduce the prevalence of delayed ischemic neurological deficit and improve early clinical outcome but failed to improve outcome at 6 months after aneurysmal subarachnoid hemorrhage. CLINICAL TRIAL REGISTRATION: URL: www.clinicaltrials.gov. Unique identifier: NCT00842049.

Surgical outcome for foot drop in lumbar degenerative disease.

Controversy exists regarding the timing and outcome of surgery for lumbar degenerative disease (LDD) associated with foot drop. In this work, we report the results of a retrospective observational study from our center. We had a sample size of 26 patients with a minimum follow-up of 6 months. Of the 26 patients, 88% improved, with complete recovery observed in 61%. Thus, our data support the view that there is good recovery from operative management of foot drop secondary to LDD. Adjusting for preoperative strength, preoperative duration of weakness was a significant predictor of extent of recovery (odds ratio = 0.93; 95% confidence interval 0.88 to 0.98; p = 0.019). The model explained 50% of the variance in outcome in this study.

New modalities to assess efficacy of triple-h therapy: early experience.

The traditional axiom that vasospasm induced reduction of blood flow leads to poor tissue oxygenation and ischaemic cellular injury culminating in delayed neurological deficits has been challenged and the efficacy of triple H therapy in reversal of the above is debated. In this study we assess cerebral physiology before and during onset of DIND and with application of triple H therapy with real time neuro-monitoring tools. Patients with Fisher grade 3/4/3 + 4/rebleed were consented. Probes for measuring rCBF, pTiO2, and Microdialysis parameters - glucose, glycerol, lactate, and pyruvate were inserted at time of coiling/clipping. Subsequent monitoring was done in HDU/ITU setting. Return of parameters to baseline was regarded as effective triple H therapy. Study is ongoing and the current paper presents our experience with first five patients. The results suggest safety and feasibility of multimodal monitoring in clinical setting to establish an understanding of relationship between clinical symptoms, brain perfusion, oxygenation, and metabolism in real time to test and guide therapy in future.

A retrospective analysis of revision endoscopic third ventriculostomy.

PURPOSE: Endoscopic third ventriculostomy (ETV) has gained favour as an effective treatment for obstructive hydrocephalus. However, the timing of ETV failure and the long-term efficacy of revision ETV remain poorly documented. METHODS: A retrospective review was performed of patients undergoing revision ETV between 1999 and 2007. Only those patients in whom there was evidence of a good sustained clinical improvement after the initial ETV were considered candidates for ETV revision. All other patients underwent insertion of a ventriculoperitoneal shunt at the time of ETV failure. Failures that were selected for repeat ETV were subdivided into; "early" if the revision occurred within the first 3 months of the primary procedure and "late" if occurring after this. RESULTS: Ten patients underwent revision ETV (6% of all ETVs performed). Age ranged from 2 months to 32 years (mean 13.6 years). Three "early" revision ETV were performed at a mean of 1.3 months, and there were seven "late" revisions performed at a mean of 27 months. The stoma was closed in seven patients and narrowed in one patient, and a second membrane was found under the original patent stoma in a further two patients. In two patients, a third ETV procedure was performed (both at 1 month after second ETV), and the stoma was closed in both these patients. No patients have required a shunt. CONCLUSION: At last follow-up (mean 38 months), all patients remain well. Revision ETV appears a safe and effective means of managing hydrocephalus-providing there is clinical evidence that the primary procedure was initially effective. It is important to emphasise that patients with an initially successful ETV are by no means "cured".

Bilateral extradural hematoma formation following excision of a thoracic intradural lesion.

The authors report an unusual case of a 15-year-old girl who previously underwent resection of a posterior fossa medulloblastoma, and later underwent resection of a thoracic extramedullary metastatic lesion. Her consciousness deteriorated hours after removal of her spinal metastasis. A CT head scan identified bilateral extradural cranial hematomas, which were evacuated. To the authors' knowledge, this is the first report of a patient developing bilateral acute cranial extradural hematomas following excision of a thoracic intradural lesion.

Endoscopic biopsy during third ventriculostomy in paediatric pineal region tumours.

OBJECTS: The goal of the study was to establish if endoscopic biopsy during third ventriculostomy contributes to morbidity in the management of paediatric pineal region tumours presenting with hydrocephalus. MATERIALS AND METHODS: This study was a retrospective descriptive study in patients less than 18 years of age who have presented with a pineal region tumour between 2000 and 2006. Data were obtained from case notes. Twelve patients had presented with a pineal region mass with symptomatic hydrocephalus. Of these, eight had endoscopic biopsy during third ventriculostomy. CONCLUSIONS: No mortality or permanent morbidity was seen following endoscopic biopsy. Two cases of transient worsening of pre-operative diplopia were noted. Diagnostic sensitivity for endoscopic biopsy is 75%. Tumour markers were not significantly raised in any plasma and cerebrospinal fluid samples. Endoscopic biopsy during third ventriculostomy in paediatric pineal region tumours is safe and results in good diagnostic yields. It should play an integral role in the initial management of patients in this setting.