Relevance of presenting risks of frailty, sarcopaenia and osteopaenia to outcomes from aneurysmal subarachnoid haemorrhage.

INTRODUCTION: Aneurysmal subarachnoid haemorrhage (aSAH) is a condition with significant morbidity and mortality. Traditional markers of aSAH have established their utility in the prediction of aSAH outcomes while frailty markers have been validated in other surgical specialties. We aimed to compare the predictive value of frailty indices and markers of sarcopaenia and osteopaenia, against the traditional markers for aSAH outcomes. METHODS: An observational study in a tertiary neurosurgical unit on 51 consecutive patients with ruptured aSAH was performed. The best performing marker in predicting the modified Rankin scale (mRS) on discharge was selected and an appropriate threshold for the definition of frail and non-frail was derived. We compared various frailty indices (modified frailty index 11, and 5, and the National Surgical Quality Improvement Program score [NSQIP]) and markers of sarcopaenia and osteopaenia (temporalis [TMT] and zygoma thickness), against traditional markers (age, World Federation of Neurological Surgery and modified Fisher scale [MFS]) for aSAH outcomes. Univariable and multivariable analysis was then performed for various inpatient and long-term outcomes. RESULTS: TMT was the best performing marker in our cohort with an AUC of 0.82, Somers' D statistic of 0.63 and Tau statistic 0.25. Of the frailty scores, the NSQIP performed the best (AUC 0.69), at levels comparable to traditional markers of aSAH, such as MFS (AUC 0.68). The threshold of 5.5 mm in TMT thickness was found to have a specificity of 0.93, sensitivity of 0.51, positive predictive value of 0.95 and negative predictive value of 0.42. After multivariate analysis, patients with TMT ≥ 5.5 mm (defined as non-frail), were less likely to experience delayed cerebral ischaemia (OR 0.11 [0.01 - 0.93], p = 0.042), any complications (OR 0.20 [0.06 - 0.069], p = 0.011), and had a larger proportion of favourable mRS on discharge (95.0% vs. 58.1%, p = 0.024) and at 3-months (95.0% vs. 64.5%, p = 0.048). However, the gap between unfavourable and favourable mRS was insignificant at the comparison of 1-year outcomes. CONCLUSION: TMT, as a marker of sarcopaenia, correlated well with the presenting status, and outcomes of aSAH. Frailty, as defined by NSQIP, performed at levels equivalent to aSAH scores of clinical relevance, suggesting that, in patients presenting with acute brain injury, both non-neurological and neurological factors were complementary in the determination of eventual clinical outcomes. Further validation of these markers, in addition to exploration of other relevant frailty indices, may help to better prognosticate aSAH outcomes and allow for a precision medicine approach to decision making and optimization of best outcomes.

Endoscopic excision of an aqueduct of Sylvius cavernoma causing obstructive hydrocephalus: technical note.

BACKGROUND AND IMPORTANCE: Acquired lesions within the aqueduct of Sylvius are rare and their surgical management is challenging. Open transcranial approaches require dissection and manipulation of surrounding eloquent structures. Use of an endoscope can avoid potential morbidity from traversing and handling eloquent structures during open approaches whilst providing better visualisation of an intraventricular lesion. CLINICAL PRESENTATION: A 62-year-old female presented with insidious onset short-term memory loss, unsteady gait, urinary incontinence and left-sided dysaesthesia. Magnetic resonance imaging (MRI) revealed hydrocephalus from an obstructive haemorrhagic lesion consistent with a cavernoma at the central midbrain within the aqueduct of Sylvius. An endoscopic approach was selected to provide optimal visualisation of the lesion. As only a single instrument could be accommodated, rotational movements were employed to tease out the lesion. Gross total resection was achieved. Her symptoms improved immediately postoperatively and she made a complete recovery by 2 months. Post-operative MRI showed resolution of hydrocephalus and no evidence of residual/recurrence of the lesion. Unfortunately, she developed hydrocephalus 3 months post-op and required placement of a ventriculoperitoneal shunt. CONCLUSIONS: Endoscopic resection is safe and feasible for selected periaqueductal lesions as it provides direct access while minimising disruption of the surrounding anatomical structures. The limitation of only having a single instrument can be overcome by employing rotational movements.

Paediatric Cerebral Arteriovenous Malformation: Outcomes from a Singapore Children's Hospital.

OBJECTIVES: Paediatric brain arteriovenous malformation (bAVM) is a rare and distinct clinical entity. There is a growing body of literature that support the success of multimodality approaches for this difficult condition. The authors aim to firstly, describe our institutional experience with a consecutive series of patients and next, corroborate our results with current literature. MATERIAL AND METHODS: This is a single institution, retrospective study conducted over a 20-year period. Patients less than 19 years old with bAVM were included. Variables of interest included patient demographics, clinical presentation, neuroimaging features, bAVM characteristics and treatment modality. Functional outcomes were measured with modified Rankin scale (mRS). RESULTS: There were 58 paediatric bAVMs, presenting at a mean age of 8.7 ± 4.2 years, and followed up for a mean duration of 7.7 years. Thirty-six patients (62.1%) underwent microsurgical resection, 10 patients had stereotactic radiosurgery (17.2%) and 2 patients had endovascular treatment (3.4%). 50 patients (86.2%) had a favourable outcome at 1-year follow up. Microsurgical resection and SRS had similar obliteration rates (resection 83.3%; SRS 80.0%) and recurrence (resection 10.0%; SRS 12.5%). There were 6 cases of bAVM recurrence (12.8%). This subgroup was noted to be less than 7.5 years old at presentation (OR 15.0, 95% CI 1.56 - 144), and less likely to present with bAVM rupture (OR 0.11, 95% CI 0.01 - 0.96). CONCLUSION: This study describes our experience in managing paediatric bAVM, whereby monomodal therapy can still be effective. Of note, we also demonstrate the role of extended surveillance to detect recurrence.

Use of Mixed Reality in Neurosurgery Training: A Single Centre Experience.

BACKGROUND: Mixed reality (MR) technology has opened new avenues for planning, visualization, and education in surgery. Neurosurgical pathologies require a very clear understanding of the relationships between pathology and critical neurovascular structures. The decline in cadaveric dissections and resource constraints has pushed the educators to find newer ways of rendering the same knowledge. The aim of this study was to determine the feasibility of employing a MR device in a high-volume center for neurosurgical teaching. The study also evaluated the results of the trainee experience in using the MR platform. METHODS: Three neurosurgical consultants who are part of the teaching faculty were asked to facilitate the session. No prior training on utilizing the MR device was given to the trainees. HoloLens 2 was used as the MR device. Two questionnaires were used to understand the experience of the trainees. RESULTS: Eight active neurosurgical trainees who are currently training at our institution were recruited for the purposes of this study. Despite having no prior training on a MR platform, the learning curve was short for most of the trainees. Whether MR replace current traditional methods of teaching neuroanatomy, the response was divided across the trainees. The results of the User Experience Questionnaire were positive with the trainees finding the device as attractive, dependable, novel, and user-friendly. CONCLUSION: This study demonstrates the feasibility of using MR platform in neurosurgery training without significant preparation requirements. These data are required to justify the future investment in this technology for training institutions.

Gods and monsters: Greek mythology and Christian references in the neurosurgical lexicon.

BACKGROUND: Myths and religion are belief systems centered around supernatural entities that attempt to explain the observed world and are of high importance to certain communities. The former is a collection of stories that belong to a cultural tradition and the latter are organized faiths that determine codes of ethics, rituals and philosophy. Deities or monstrous creatures in particular act as archetypes instructing an individual's conduct. References to them in Greek mythology and Christianity are frequently manifested in the modern neurosurgical vernacular. METHODS: A review of the medical literature was performed using the PubMed and MEDLINE bibliographic databases. Publications from 1875 to 2021 related to neurosurgery or neuroanatomy with the medical subject headings (MeSH) terms mythology, religion, Christianity and Catholicism were reviewed. References pertaining to supernatural beings were classified to either a deity or a monstrosity according to their conventional cultural context. RESULTS: Twelve narratives associated with neurosurgery were identified, nine relating to Greek mythology and three associated with the Christian-Catholic faith. Eight accounts concerned deities and the remaining with monstrous creatures. CONCLUSION: This article explores the etymology of commonly utilized terms in daily neurosurgical practice in the context of mythology and religion. They reveal the ingenuity and creativity of early pioneers who strived to understand the brain.

Hyperostosing sphenoid wing meningiomas.

Some sphenoid wing meningiomas are associated with a significant hyperostotic reaction of the adjacent sphenoid ridge that may even exceed the size of the intradural mass. The decision-making process and surgical planning based on neuroanatomic knowledge are the mainstays of management of this group of lesions. Given their natural history and biologic behavior, many hyperostosing meningiomas at this location require long-term management analogous to a chronic disease. This is particularly true when making initial decisions regarding treatment and planning surgical intervention, when it is important to take into consideration the possibility of further future interventions during the patient's life span.

Neurocysticercosis Diagnosed by Taenia solium PCR on Brain Biopsy.

Neurocysticercosis is a common cause for brain lesions and adult-onset epilepsy in endemic countries. However, diagnosis is challenging in the absence of typical radiologic or histopathologic features. In this case report, we present a case of a 35-year-old male with a new-onset seizure and a rim-enhancing temporal lobe lesion. Radiologic features were nonspecific, and brain biopsy was performed. Histologic features showed only nonspecific granulomatous inflammation, and the diagnosis of neurocysticercosis was confirmed only with polymerase chain reaction (PCR) testing on brain biopsy tissue demonstrating PCR products consistent with Taenia solium. This case highlights the diagnostic role of PCR in such clinical situations whereby the diagnosis is unclear after initial routine evaluation.

Aqueductal Compression by Dilated Virchow-Robin Spaces in the Mesencephalic-Pontine Region Presenting with Symptoms Mimicking Normal Pressure Hydrocephalus: A Case Report and Review of Literature.

BACKGROUND: Dilatation of Virchow-Robin spaces (dVRS) have been described in the development of hydrocephalic syndromes. We report an unusual case of a type III dVRS presenting as a mimic of normal pressure hydrocephalus (NPH), due to distortion at the level of the cerebral aqueduct. CASE DESCRIPTION: A 59-year-old woman presented with mild traumatic brain injury and possible NPH, due to a history of progressive gait disturbance, recurrent falls, and cognitive decline over a year, in the context of ventriculomegaly. Detailed structural imaging of the brain revealed multiple dilated cystic lesions consistent with dVRS causing distortion at the level of the cerebral aqueduct. Cerebrospinal fluid examination was negative for infection. The patient was treated with endoscopic third ventriculostomy; at 12 months postoperatively, she demonstrated a sustained improvement in gait and stabilization of cognitive decline. CONCLUSIONS: This is an illustrative case of a subacute obstructive hydrocephalus due to a collection of periaqueductal dVRS, leading to an insidious clinical presentation mimicking NPH. We reviewed the literature for key clinical presentations and describe neuroanatomical considerations as well as primary treatment strategies. Various hydrocephalic syndromes may present with classic symptoms from Hakim's triad; such symptoms are not specific to idiopathic NPH. Both endoscopic third ventriculostomy and shunting may be efficacious. In our case, dVRS may serve as both a cause of and compensatory mechanism in a subacute obstructive hydrocephalus of unknown etiology. Our case highlights the need to understand the neuroanatomy of aberrant cerebrospinal fluid spaces in hydrocephalic syndromes. Further studies of dVRS would provide valuable insights into the pathogenesis of hydrocephalus.

Concomitant Primary CNS Lymphoma and FSH-Pituitary Adenoma Arising Within the Sella. Entirely Coincidental?

BACKGROUND AND IMPORTANCE: Collision tumors are the simultaneous occurrence of more than one type of neoplasm within an anatomic space. In the pituitary sella, collision tumors are exceedingly rare, and not much is known about their etiology and prognosis. CLINICAL PRESENTATION: A 74-year-old man presented with a concomitant primary pituitary lymphoma (diffuse large B-cell non-Hodgkin's lymphoma; DLBCL) and follicle-stimulating hormone (FSH)-adenoma diagnosed histologically after clinical features of apoplexy prompted urgent surgical decompression and resection. Strong immunoreactivity for FSH by the lymphoma was evident. Full-body workup demonstrated no other source for the lymphoma. He subsequently underwent 4 cycles of chemotherapy and has been in remission for over 32 months. His ophthalmoplegia at presentation persisted with no further deficits. CONCLUSIONS: Four cases of collision tumors of primary pituitary lymphoma and adenoma have previously been reported. This case represents the first combination of an FSH-adenoma and a DLBCL in the literature. Prompt involvement of the hematology-oncology team contributed to the good outcome seen in this case. The putative role played by pituitary hormones in tumorigenesis is reviewed in this case report. The association is either a chance occurrence or due to the induction of lymphoma cell proliferation by the binding of FSH produced by the adenoma to the FSH receptors on the lymphoma cells.

Neurosurgical endoscopic training via a realistic 3-dimensional model with pathology.

INTRODUCTION: Training in intraventricular endoscopy is particularly challenging because the volume of cases is relatively small and the techniques involved are unlike those usually used in conventional neurosurgery. Present training models are inadequate for various reasons. Using 3-dimensional (3D) printing techniques, models with pathology can be created using actual patient's imaging data. This technical article introduces a new training model based on a patient with hydrocephalus secondary to a pineal tumour, enabling the models to be used to simulate third ventriculostomies and pineal biopsies. METHODS: Multiple models of the head of a patient with hydrocephalus were created using 3D rapid prototyping technique. These models were modified to allow for a fluid-filled ventricular system under appropriate tension. The models were qualitatively assessed in the various steps involved in an endoscopic third ventriculostomy and intraventricular biopsy procedure, initially by 3 independent neurosurgeons and subsequently by 12 participants of an intraventricular endoscopy workshop. RESULTS: All 3 surgeons agreed on the ease and usefulness of these models in the teaching of endoscopic third ventriculostomy, performing endoscopic biopsies, and the integration of navigation to ventriculoscopy. Their overall score for the ventricular model realism was above average. The 12 participants of the intraventricular endoscopy workshop averaged between a score of 4.0 to 4.6 of 5 for every individual step of the procedure. DISCUSSION: Neurosurgical endoscopic training currently is a long process of stepwise training. These 3D printed models provide a realistic simulation environment for a neuroendoscopy procedure that allows safe and effective teaching of navigation and endoscopy in a standardized and repetitive fashion.