A common tumour in a rare location: a single centre case series of cerebellar glioblastoma.

Although glioblastoma is the commonest primary brain tumour in adults, its location in the cerebellum is extremely rare. We present thirteen cases (3 female, 10 male; median age at presentation 56 [age range 21-77]) of surgically managed, histologically confirmed, primary cerebellar glioblastoma (cGB) over a 17 year period (2005-2022). Pre-operative radiological diagnosis was challenging given cGB rarity, although MRI demonstrated ring enhancement in all cases. Surgical management included posterior fossa craniectomy and debulking in 11 cases and burr hole biopsy in two. CSF diversion was necessary in four cases. No evidence of IDH or ATRX gene mutations was found when tested. Survival ranged from 1 to 22 months after diagnosis (mean 10.9 months). We also seek to understand why glioblastoma is rare in this location and discuss potential reasons for this. We hypothesise that increasing anatomical distance from germinal regions and decreased local endogenous neural stem cell activity (which has been associated with glioblastoma) may explain why glioblastoma is rare in the cerebellum. We hereby seek to add to the limited literature on cGB as this is the largest UK cGB series to date.

Surgery for Malignant Acute Ischemic Stroke: A Narrative Review of the Knowns and Unknowns.

Malignant acute ischemic stroke (AIS) is characterized by acute neurological deterioration caused by progressive space-occupying brain edema, often occurring in the first hours to days after symptom onset. Without any treatment, the result is often fatal. Despite advances in treatment for AIS, up to 80% of patients with a large hemispheric stroke or cerebellar stroke are at risk of poor outcome. Decompressive surgery can be life-saving in a subgroup of patients with malignant AIS, but uncertainties exist on patient selection, predictors of malignant infarction, perioperative management, and timing of intervention. Although survivors are left disabled, most agree with the original decision to undergo surgery and would make the same decision again. In this narrative review, we focus on the clinical and radiological predictors of malignant infarction in AIS and outline the technical aspects of decompressive surgery as well as duraplasty and cranioplasty. We discuss the current evidence and recommendations for surgery in AIS, highlighting gaps in knowledge, and suggest directions for future studies. KEY POINTS: · Acute ischemic stroke from occlusion of a proximal intracranial artery can progress quickly to malignant edema, which can be fatal in 80% of patients despite medical management.. · Decompression surgery is life-saving within 48 hours of stroke onset, but the benefits beyond this time and in the elderly are unknown.. · Decompressive surgery is associated with high morbidity, particularly in the elderly. The decision to operate must be made after considering the individual's preference and expectations of quality of life in the context of the clinical condition.. · Further studies are needed to refine surgical technique including value of duraplasty and understand the role monitoring intracranial pressure during and after decompressive surgery.. · More studies are needed on the pathophysiology of malignant cerebral edema, prediction models including imaging and biomarkers to identify which subgroup of patients will benefit from decompressive surgery.. · More research is needed on factors associated with morbidity and mortality after cranioplasty, safety and efficacy of implants, and comparisons between them.. · Further studies are needed to assess the long-term effects of physical disability and quality of life of survivors after surgery, particularly those with severe neurological deficits..

Olfactory neuroblastoma limited to sphenoid sinus.

Olfactory neuroblastoma (ONB) is a rare tumour of the skull base, typically originating from the nasal cavity and around the cribriform plate. We present the rare case of ONB originating from and limited to the sphenoid sinus in a 42-year old lady. Pre-operatively the lesion was thought to be a sinonasal polyp and underwent functional endoscopic sinus surgery (FESS) and total excision of the polypoid lesion. Review of histology unexpectedly revealed ONB. She underwent further surgery to ensure wide local excision was achieved with negative margins on histology, followed by radiotherapy. This is only the third reported case of ONB limited to the sphenoid sinus and the ninth reported case of primary sphenoid ONB in the literature. We review the literature pertaining with primary sphenoidal ONB here and suggest complete resection is indicated in ectopic ONB, not unlike classical ONB. There may be a role for adjuvant oncological treatments and lifelong follow up in a multidisciplinary approach is recommended.

Coughing on the coil; a case report and literature review of eight cases of endovascularly treated ICA pseudoaneurysms with coil migration into the oropharnyx.

We report a case of coil migration into the oropharynx five years after treatment of a left internal carotid pseudoaneurysm following abandoned transsphenoidal resection of a pituitary macroadenoma. Eight other cases were found on literature review, with coil migration occurring between 2 and 120 months often after a history of transsphenoidal surgery. The majority of these were treated with trimming in a day case setting. This report highlights the need for careful extended follow up when a pseudoaneurysm forms with a concurrent skull base deficit.

Facet joint cyst haematoma: a rare cause of cauda equina syndrome.

Facet joint cysts are a feature of lumbar spondylosis and are an uncommon cause of radiculopathy. Facet joint cyst haematoma is a very rare entity and has previously been reported as a subacute cause of leg pain, back pain, sensory deficit and lower limb weakness. We present the unique case of facet joint cyst haematoma presenting as cauda equina syndrome. An 81 year old lady presented with a 7 day history of back pain and left foot drop, a 1 day history of perineal numbness and urinary retention with absent rectal tone, perianal anaesthesia and left leg hypoaesthesia. Emergency MRI scan demonstrated spinal canal stenosis as the aetiology of her cauda equina syndrome. She was taken to theatre for emergency lumbar decompression. At operation a facet joint haematoma compressing the cauda equina was found and extirpated with complete resolution of symptoms. In this case, the aetiology of cauda equina compression was not demonstrated effectively on pre-operative MRI scanning.

Terson syndrome in reverse: intraventricular haemorrhage following primary intraocular haemorrhage.

Terson syndrome (TS) describes the presence of intraocular haemorrhage in patients with intracranial haemorrhage or traumatic brain injury. The aetiology of TS is controversial as an anatomical conduit between the vitreous humour and subarachnoid space remains contested. We herewith present a case of primary vitreous haemorrhage with secondary intracranial extension into the ventricles. Cranial CT demonstrates blood within the left optic nerve and chiasm but not within the subarachnoid space. This unusual phenomenon, which has not been reported before, may be described as 'Terson syndrome in reverse'. We explore mechanisms by which blood within the globe may track into the ventricular system, contextualising recent advances in the understanding of ocular-intracranial fluid transport.

Psychrobacter piechaudii shunt infection: first report of human infection.

Psychrobacter piechaudii is a recently described species of Gram-negative bacteria in the Moraxellaceae family. No cases of human infection due to this species have been described before. We report the case of an ex-premature infant girl with hydrocephalus secondary to intraventricular haemorrhage who underwent multiple cerebrospinal fluid (CSF) shunt operations. She ultimately developed Psychrobacter piechaudii meningitis, presenting as ventriculoperitoneal shunt dysfunction and wound leak, which necessitated removal of the shunt, a period of external ventricular drainage and antibiotics. We found this organism to be sensitive to intravenous ceftazidime (50 mg/kg) and ciprofloxacin, and a 7-10 day treatment course prior to shunt re-insertion (and 3 week total course) was sufficient. The patient is well post-operatively. To the best of our knowledge, this is the first reported case of Psychrobacter piechaudii infection in a human.

Glioblastoma in Beckwith-Wiedemann syndrome: first case report and review of potential pathomechanisms.

Beckwith-Wiedemann syndrome (BWS) is a rare congenital overgrowth syndrome associated with certain childhood tumours. We present the case of a 36-year-old lady with BWS who developed a left frontoinsular secondary glioblastoma. This is the first case report in the literature of glioblastoma associated with BWS. We explore similarities in the molecular pathomechanisms of BWS and glioblastoma.

Observations on the anti-glioma potential of electrical fields: is there a role for surgical neuromodulation?

Alternating electrical field therapy represents a recent addition to the armamentarium against high grade glioma. Randomised trial evidence suggests a survival benefit from adjunctive scalp delivered Tumour Treating Fields (TTFields) in glioblastoma. Any underlying anti-glioma effect is not fully understood, but interference with cell division and microtubule assembly has been averred. The survival benefit claimed for TTFields is modest and is associated with mild reductions in health-related quality of life indices amid costs that presently preclude routine use. I review possible mechanisms by which alternating electrical fields may confer an anti-glioma effect. As scalp and skull are poor conductors of an electrical field, a case is made here for implantable electrodes, perhaps placed at the time of tumour debulking. Such a system may deliver an electrical field directly to the tumour resection cavity and with greater precision.

Trigeminal schwannoma presenting as a gelastic seizure: no laughing matter.

We present the case of a 66 year old gentleman with trigeminal schwannoma whose only presenting feature was a single gelastic seizure. This is the first case report of pathological laughter in trigeminal schwannoma in the absence of other trigeminal, brainstem, cerebellar or other cranial nerve dysfunction.

Glioblastoma multiforme metastatic to lung in the absence of intracranial recurrence: case report.

We present the case of a 65 year old gentleman who underwent craniotomy and debulking of a left temporal glioblastoma multiforme (GBM). Post-operatively he received chemotherapy and radiotherapy with good response demonstrated on interval MRI scans. At 17 months post-diagnosis and in the absence of clinical or radiological recurrence, he presented with respiratory distress. He was found to have an exudative right-sided pleural effusion, nodular pleural thickening, a hilar mass and associated lymphadenopathy. Percutaneous pleural biopsy revealed metastatic GBM. Systemic GBM metastasis despite good response to oncological treatments and in the absence of intracranial recurrence is exceedingly rare. We review the literature concerning extra-neuraxial GBM metastasis and speculate why this phenomenon is extremely rare.

A case of malignant cerebral infarction associated with COVID-19 infection.

Stroke as a presenting feature of COVID-19 infection is being increasingly recognized. We describe a case of a 46-year-old healthcare worker with COVID-19 who developed malignant cerebral infarction requiring emergency decompressive craniectomy. This case illustrates the neurosurgical implications associated with inflammatory and pro-coagulopathic derangements in COVID-19 disease.

Successful treatment of giant cavernous carotid artery aneurysm in a child using a flow diverter stent.

Giant intracranial aneurysms are extremely rare in children. We present such a case, describe angiographic appearances and successful treatment using a flow diverter stent.

Beating a skullduggerous infantile hemispheric high-grade glioma.

A case of infantile hemispheric high grade glioma in a five-month-old boy is presented. Striking images of a 'beaten copper pot' skull were concerning at first, but with a successful surgical and oncological plan he is well three years later, displaying only minor signs of developmental delay.

Dissection using pulsed radiofrequency energy device (PlasmaBlade) is safe and efficient in experimental revision neuromodulation implant surgery.

BACKGROUND: The use of functional neurosurgical implants has increased over the past 10 years. PlasmaBlade is an innovative electrosurgical appliance harnessing pulsed radiofrequency (RF) energy. Our aim was to assess the risk of damage to neuromodulation hardware during PlasmaBlade dissection. MATERIALS AND METHODS: A simulated setting with chicken breast threaded with different hardware and PlasmaBlade used in three configurations. . Post dissection, the wires were inspected naked eye and under an operating microscope. The induced current was assessed contemporaneously using an oscilloscope. RESULTS: Five surgeons tested the PlasmaBlade at different generator settings. Sixty dissections were undertaken. No structural damage or induced current was identified at CUT 3/4, COAG 5. At CUT 6, COAG 5 and during dissection in a perpendicular orientation with prolonged hardware contact, opacification of insulation material occurred in 15/20 dissections. There was no dissolution of insulation even at this setting. On deviation from Medtronic advice, hardware damaged occurred if one was reckless with the PlasmaBlade. CONCLUSION: When using the recommended settings and operational technique, PlasmaBlade dissection did not cause any damage to implant wiring/tubing in this simulated setting. This report seeks to add to clinical data suggesting PlasmaBlade is safe for dissection around deep brain stimulator (DBS), vagal nerve stimulator (VNS), and spinal cord stimulator (SCS) hardware.

The evolution of an SBNS-accredited NANSIG simulated skills workshop for aspiring neurosurgical trainees: an analysis of qualitative and quantitative data.

BACKGROUND: The Neurology and Neurosurgery Interest Group (NANSIG) neurosurgical skills workshop is novel in teaching neurosurgical skills solely to medical students and foundation trainees in the UK. The aim is to offer an affordable option for a high-fidelity simulation course enabling students to learn and practise specific neurosurgical skills in a safe, supervised environment. METHODS: A 10-delegate cohort was quantitatively assessed at the NANSIG neurosurgical skills workshop. Two assessors used a novel modified Objective Structured Assessment of Technical Skills (mOSATS) assessment tool, comprising 5 domains ranked according to a 5-point scale to rate delegates' ability to create a burr hole. Qualitative data from previous workshops were collected, consisting of open-ended, closed-ended and 5-point Likert scale responses to pre- and post-workshop questionnaires. Data were analysed using SPSS® software. RESULTS: Delegates scored a mean total of 62.1% (21.75/35) and 85.1% (29.8/35) in pre- and post-workshop assessments respectively revealing a statistically significant improvement. Regarding percentage of improvement, no significant difference was shown amongst candidates when comparing the number of neurosurgical cases observed and/or assisted in the past. There was no significant difference in the overall rating between the last two workshops (4.89 and 4.8 out of 5, respectively). One hundred percent of the attendees reported feeling more confident in assisting in theatre after the last two workshops. CONCLUSION: We show that a simulation workshop cannot only objectively quantify the improvement of surgical skill acquisition but can also be beneficial regardless of the extent of prior experience.

Spontaneous regression of a large skull base meningioma: case report.

We present the case of a 58 year old lady with a large middle cranial fossa meningioma (5 cm × 4 cm in maximal dimensions) which has considerably regressed without any treatment during seven years of follow up. While the tumour had remained radiologically static for the first three years, scans from year five post-diagnosis onwards have shown shrinkage of the meningioma from a calculated volume of 36 cm3 to 11.2 cm3. There has been no intratumoral haemorrhage or infarction and no medication or exogenous hormonal effect that could account for this effect. We reviewed the literature and report that this is only the second ever case of spontaneous regression of meningioma.

Speech bubble: dysphasia secondary to spontaneous intraparenchymal pneumocephalus.

Spontaneous pneumocephalus is exceptionally rare, with few published cases in the literature. We describe a patient presenting with dysphasia, right facial weakness, headache and confusion who was subsequently found to have pneumocephalus due to an encephalocoele herniating into a tegmen tympani defect.

Advancing spinal fellowship training: an international multi-centre educational perspective.

PURPOSE: The purpose of this article is to review the importance of contemporary spine surgery fellowships and educational strategies to assist with fellowship design and delivery. METHODS: Spine surgery fellowship includes trainees from orthopaedic and neurosurgical backgrounds and is increasingly indicated for individuals wishing to pursue spine surgery as a career, recognizing how spinal surgery evolved significantly in scope and complexity. We combine expert opinion with a review of the literature and international experience to expound spine fellowship training. RESULTS: Contemporary learning techniques include boot camps at the start of fellowship which may reinforce previous clinical learning and help prepare fellows for their new clinical roles. There is good evidence that surgical specialty training boot camps improve clinical skills, knowledge and trainee confidence prior to embarking upon new clinical roles with increasing levels of responsibility. Furthermore, as simulation techniques and technologies take on an increasing role in medical and surgical training, we found evidence that trainees' operative skills and knowledge can improve with simulated operations, even if just carried out briefly. Finally, we found evidence to suggest a role for establishing competence-based objectives for training in specific operative and technical procedures. Competence-based objectives are helpful for trainees and trainers to highlight gaps in a trainee's skill set that may then be addressed during training. CONCLUSIONS: Spinal fellowships may benefit from certain contemporary strategies that assist design and delivery of training in a safe environment. Interpersonal factors that promote healthy teamwork may contribute to an environment conducive to learning. These slides can be retrieved under Electronic Supplementary Material.