Intra-operative extracorporeal irradiation of tumour-invaded craniotomy bone flap in meningioma: a case series.

BACKGROUND: Extracorporeal irradiation of tumorous calvaria (EITC) can be performed to restore function and form of the skull after resection of bone-invasive meningioma. We sought to examine the rate of tumour recurrence and other selected outcomes in patients undergoing meningioma resection and EITC. METHODS: Retrospective single-centre study of adult patients undergoing meningioma resection and EITC between January 2015 and November 2022 at a tertiary neurosurgical centre. Patient demographics, surgery data, tumour data, use of adjuvant therapy, surgical complications, and tumour recurrences were collected. RESULTS: Eighteen patients with 11 (61%) CNS WHO grade 1, 6 (33%) grade 2, and 1 (6%) grade 3 meningiomas were included. Median follow-up was 42 months (range 3-88). Five (28%) patients had a recurrence, but none were associated with the bone flap. Two (11%) wound infections requiring explant surgery occurred. Six (33%) patients required a further operation. Two operations were for recurrences, one was for infection, one was a washout and wound exploration but no evidence of infection was found, one patient requested the removal of a small titanium implant, and one patient required a ventriculoperitoneal shunt for a persistent CSF collection. There were no cases of bone flap resorption and cosmetic outcome was not routinely recorded. CONCLUSION: EITC is feasible and fast to perform with good outcomes and cost-effectiveness compared to other reconstructive methods. We observed similar recurrence rates and lower infection rates requiring explant compared to the largest series of cranioplasty in meningioma. Cosmetic outcome is universally under-reported and should be reported in future studies.

Antiplatelet therapy in aneurysmal subarachnoid hemorrhage: an updated meta-analysis.

Antiplatelet therapy (AT) may serve to reduce the effects of aneurysmal subarachnoid hemorrhage (aSAH)-induced pro-coagulant state in the cerebral circulation. Several studies, however, have delivered conflicting conclusions on the efficacy of AT post aSAH. Systematic searches of Medline, Embase, and Cochrane Central were undertaken on 27th March 2023. The primary outcome was delayed cerebral ischaemia (DCI). Secondary outcomes were symptomatic and angiographic vasospasm, good functional outcome (modified Rankin Scale [mRS] with scores 0-2), hemorrhagic events, and in-hospital mortality. Twenty-two studies reporting 4378 patients with aSAH were included in the meta-analysis. AT was associated with lower rates of DCI (RR=0.62, 95% CI: 0.43; 0.89), symptomatic vasospasm (RR=0.63, 95% CI: 0.46; 0.86), and moderate/severe angiographic vasospasm (RR=0.74, 95% CI: 0.65; 0.84), with no effect on hemorrhagic complications (RR=1.36, 95% CI: 0.77; 2.41). When analyzing only post-ictal use of AT, AT additionally favored rates of good functional outcomes (RR=1.18, 95% CI: 1.10; 1.26) and in-hospital mortality (RR=0.56, 95% CI: 0.39; 0.80). In the subgroup treated with cilostazol, AT was associated with lower rates of DCI (RR=0.40, 95% CI: 0.32), symptomatic vasospasm (RR=0.47, 95% CI: 0.33; 0.65), moderate/severe angiographic vasospasm (RR=0.75, 95% CI: 0.57; 0.98) and good functional outcome (RR=1.24, 95% CI: 1.08; 1.43). In the surgically treated aSAH subgroup, AT favored rates of symptomatic vasospasm (RR=0.55, 95% CI: 0.30; 0.98), moderate/severe angiographic vasospasm (RR=0.70, 95% CI: 0.54; 0.90) and good functional outcome (RR=1.23, 95% CI: 1.09; 1.41). In the endovascularly treated aSAH subgroup, AT was associated with lower rates of in-hospital mortality (RR=0.60, 95% CI: 0.41; 0.88). In aSAH patients, post-ictal AT is associated with benefits in terms of rates of DCI, vasospasm, good functional outcomes, and in-hospital mortality without an increased risk of hemorrhagic events.

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.

The evolution of intracranial aneurysm treatment techniques and future directions.

Treatment techniques and management guidelines for intracranial aneurysms (IAs) have been continually developing and this rapid development has altered treatment decision-making for clinicians. IAs are treated in one of two ways: surgical treatments such as microsurgical clipping with or without bypass techniques, and endovascular methods such as coiling, balloon- or stent-assisted coiling, or intravascular flow diversion and intrasaccular flow disruption. In certain cases, a single approach may be inadequate in completely resolving the IA and successful treatment requires a combination of microsurgical and endovascular techniques, such as in complex aneurysms. The treatment option should be considered based on factors such as age; past medical history; comorbidities; patient preference; aneurysm characteristics such as location, morphology, and size; and finally the operator's experience. The purpose of this review is to provide practicing neurosurgeons with a summary of the techniques available, and to aid decision-making by highlighting ideal or less ideal cases for a given technique. Next, we illustrate the evolution of techniques to overcome the shortfalls of preceding techniques. At the outset, we emphasize that this decision-making process is dynamic and will be directed by current best scientific evidence, and future technological advances.

Long-term oncological outcomes after haemorrhagic apoplexy in pituitary adenoma managed operatively and non-operatively.

INTRODUCTION: Depending on severity of presentation, pituitary apoplexy can be managed with acute surgery or non-operatively. We aim to assess long-term tumour control, visual and endocrinological outcomes following pituitary apoplexy with special emphasis on patients treated non-operatively. METHODS: Multicentre retrospective cohort study. All patients with symptomatic pituitary apoplexy were included. Patients were divided into 3 groups: group 1: surgery within 7 days; group 2: surgery 7 days-3 months; group 3: non-operative. Further intervention for oncological reasons during follow-up was the primary outcome. Secondary outcome measures included visual and endocrinological function at last follow-up. RESULTS: One hundred sixty patients were identified with mean follow-up of 48 months (n = 61 group 1; n = 34 group 2; n = 64 group 3). Factors influencing decision for surgical treatment included visual acuity loss (OR: 2.50; 95% CI: 1.02-6.10), oculomotor nerve palsy (OR: 2.80; 95% CI: 1.08-7.25) and compression of chiasm on imaging (OR: 9.50; 95% CI: 2.06-43.73). Treatment for tumour progression/recurrence was required in 17%, 37% and 24% in groups 1, 2 and 3, respectively (p = 0.07). Urgent surgery (OR: 0.16; 95% CI: 0.04-0.59) and tumour regression on follow-up (OR: 0.04; 95% CI: 0.04-0.36) were independently associated with long-term tumour control. Visual and endocrinological outcomes were comparable between groups. CONCLUSION: Urgent surgery is an independent predictor of long-term tumour control following pituitary apoplexy. However, 76% of patients who successfully complete 3 months of non-operative treatment may not require any intervention in the long term.

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.

Comparison of health-related quality of life in patients with traumatic brain injury, subarachnoid haemorrhage and cervical spine disease.

PURPOSE: The degree of disability that is acceptable to patients following traumatic brain injury (TBI) continues to be debated. While the dichotomization of outcome on the Glasgow Outcome Score (GOSE) into 'favourable' and 'unfavourable' continues to guide clinical decisions, this may not reflect an individual's subjective experience. The aim of this study is to assess how patients' self-reported quality of life (QoL) relates to objective outcome assessments and how it compares to other debilitating neurosurgical pathologies, including subarachnoid haemorrhage (SAH) and cervical myelopathy. METHOD: A retrospective analysis of over 1300 patients seen in Addenbrooke's Hospital, Cambridge, UK with TBI, SAH and patients pre- and post- cervical surgery was performed. QoL was assessed using the SF-36 questionnaire. Kruskal-Wallis test was used to analyse the difference in SF-36 domain scores between the four unpaired patient groups. To determine how the point of dichotomization of GOSE into 'favourable' and 'unfavourable' outcome affected QOL, SF-36 scores were compared between GOSE and mRS. RESULTS: There was a statistically significant difference in the median Physical Component Score (PCS) and Mental Component Score (MCS) of SF-36 between the three neurosurgical pathologies. Patients with TBI and SAH scored higher on most SF-36 domains when compared with cervical myelopathy patients in the severe category. While patients with Upper Severe Disability on GOSE showed significantly higher PC and MC scores compared to GOSE 3, there was a significant degree of variability in individual responses across the groups. CONCLUSION: A significant number of patients following TBI and SAH have better self-reported QOL than cervical spine patients and patients' subjective perception and expectations following injury do not always correspond to objective disability. These results can guide discussion of treatment and outcomes with patients and families.

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.

A critical appraisal of Monro's erroneous description of the cerebral interventricular foramina: Age-related magnetic resonance imaging spatial morphometry and a proposed new terminology.

Anatomic connections between the cerebral lateral and third ventricles have been mischaracterized since Monro's original erroneous description of his eponymous foramina (FoMs) as being only one T-shaped passage. Accurate knowledge of the in vivo three-dimensional (3D) configuration of FoM has important clinical neuroendoscopic, neurosurgical, and neuroimaging implications. We retrospectively analyzed volumetric high-resolution brain magnetic resonance imaging of 100 normal individuals to characterize the normal spatial anatomy and morphometry for each FoM. We measured the true anatomical 3D angulations of FoMs relative to standard neuroimaging orthogonal planes, and their minimum width, depth, and distance between the medial borders of bilateral FoMs. The right and left FoMs were separate, distinct, and in a V-shaped configuration. Each FoM was a round, oval, or crescent-shaped canal-like passage with well-defined borders formed by the semicircular concavity of the ipsilateral forniceal column. The plane of FoM was angled on average 56.8° ± 9.1° superiorly from the axial plane, 22.5° ± 10.7° laterally, and 37.0° ± 6.9° anteriorly from the midsagittal plane; all these angles changing significantly with increasing age. The mean narrowest diameter of FoM was 2.8 ± 1.2 mm, and its depth was 2.5 ± 0.2 mm. Thus, the true size and orientation of FoM differs from that depicted on standard neuroimaging. Notably, in young subjects, FoM has a diameter smaller than its depth, a configuration akin to a short, small canal. We propose that the eponym "Monro" no longer be associated with this structure, and the term "foramen" be abandoned. Instead, FoM should be more appropriately renamed as the "interventricular canaliculus," or IVC, for short.

Indocyanine green fluorescence video angiography reduces vascular injury-related morbidity during micro-neurosurgical clipping of ruptured cerebral aneurysms: a retrospective observational study.

BACKGROUND: Specific procedural complications in aneurysm surgery are broadly related to vascular territory compromise and brain/nerve retraction; vascular complications account for about half of this. Intraoperative indocyanine green video angiography (ICG-VA) provides real-time high spatial resolution imaging of the cerebrovascular architecture, allowing immediate quality assurance of aneurysm occlusion and vessel integrity. The aim of this study was to examine whether the routine use of ICG-VA reduced early procedural complications related to vascular compromise or injury during micro-neurosurgical clipping of ruptured cerebral aneurysms. METHODS: Retrospective comparative observational study of 412 adult good-grade (WFNS 1 or 2) SAH patients who had undergone microsurgical clipping without (n = 200, 2001-2004) or with (n = 212, 2009-2015) ICG-VA in a high-volume neurosurgical centre. RESULTS: The ICG-VA group had a significantly lower incidence of procedural vascular complications (7/212; 3.3%) compared with the non-ICG-VA group (19/200; 9.5%) (Fisher's exact test p = 0.0137). CONCLUSIONS: ICG-VA is a straightforward, easy-to-use, intraoperative adjunct which significantly reduces avoidable 'technical error' related morbidity.

Subarachnoid haemorrhage with negative initial neurovascular imaging: a systematic review and meta-analysis.

BACKGROUND: In patients with spontaneous subarachnoid haemorrhage (SAH), a vascular cause for the bleed is not always found on initial investigations. This study aimed to systematically evaluate the delayed investigation strategies and clinical outcomes in these cases, often described as "non-aneurysmal" SAH (naSAH). METHODS: A systematic review was performed in concordance with the PRISMA checklist. Pooled proportions of primary outcome measures were estimated using a random-effects model. RESULTS: Fifty-eight studies were included (4473 patients). The cohort was split into perimesencephalic naSAH (PnaSAH) (49.9%), non-PnaSAH (44.7%) and radiologically negative SAH identified on lumbar puncture (5.4%). The commonest initial vascular imaging modality was digital subtraction angiography. A vascular abnormality was identified during delayed investigation in 3.9% [95% CI 1.9-6.6]. There was no uniform strategy for the timing or modality of delayed investigations. The pooled proportion of a favourable modified Rankin scale outcome (0-2) at 3-6 months following diagnosis was 92.0% [95% CI 86.0-96.5]. Complications included re-bleeding (3.1% [95% CI 1.5-5.2]), hydrocephalus (16.0% [95% CI 11.2-21.4]), vasospasm (9.6% [95% CI 6.5-13.3]) and seizure (3.5% [95% CI 1.7-5.8]). Stratified by bleeding pattern, we demonstrate a higher rate of delayed diagnoses (13.6% [95% CI 7.4-21.3]), lower proportion of favourable functional outcome (87.2% [95% CI 80.1-92.9]) and higher risk of complications for non-PnaSAH patients. CONCLUSION: This study highlights the heterogeneity in delayed investigations and outcomes for patients with naSAH, which may be influenced by the initial pattern of bleeding. Further multi-centre prospective studies are required to clarify optimal tailored management strategies for this heterogeneous group of patients.

Predictors of early progression of surgically treated atypical meningiomas.

BACKGROUND: Clinical behaviour of atypical meningiomas is not uniform. While, as a group, they exhibit a high recurrence rate, some pursue a more benign course, whereas others progress early. We aim to investigate the imaging and pathological factors that predict risk of early tumour progression and to determine whether early progression is related to outcome. METHODS: Adult patients with WHO grade II meningioma treated in three regional referral centres between 2007 and 2014 were included. MRI and pathology characteristics were assessed. Gross total resection (GTR) was defined as Simpson 1-3. Recurrence was classified into early and late (≤ 24 vs. > 24 months). RESULTS: Among the 220 cases, 37 (16.8%) patients progressed within 24 months of operation. Independent predictors of early progression were subtotal resection (STR) (p = 0.005), parafalcine/parasagittal location (p = 0.015), peritumoural oedema (p = 0.027) and mitotic index (MI) > 7 (p = 0.007). Adjuvant radiotherapy was negatively associated with early recurrence (p = 0.046). Thirty-two per cent of patients with residual tumour and 26% after GTR received adjuvant radiotherapy. There was a significantly lower proportion of favourable outcomes at last follow-up (mRS 0-1) in patients with early recurrence (p = 0.001). CONCLUSIONS: Atypical meningiomas are a heterogeneous group of tumours with 16.8% patients having recurrence within 24 months of surgery. Residual tumour, parafalcine/parasagittal location, peritumoural oedema and a MI > 7 were all independently associated with early recurrence. As administration of adjuvant radiotherapy was not protocolised in this cohort, any conclusions about benefits of irradiation of WHO grade II meningiomas should be viewed with caution. Patients with early recurrence had worse neurological outcome. While histological and imaging characteristics provide some prognostic value, further molecular characterisation of atypical meningiomas is warranted to aid clinical decision making.

Tablets at the bedside - iPad-based visual field test used in the diagnosis of Intrasellar Haemangiopericytoma: a case report.

BACKGROUND: In the assessment of a pituitary mass, objective visual field testing represents a valuable means of evaluating mass effect, and thus in deciding whether surgical management is warranted. CASE PRESENTATION: In this vignette, we describe a 73 year-old lady who presented with a three-week history of frontal headache, and 'blurriness' in the left side of her vision, due to a WHO grade III anaplastic haemangiopericytoma compressing the optic chiasm. We report how timely investigations, including an iPad-based visual field test (Melbourne Rapid Field, (MRF)) conducted at the bedside aided swift and appropriate management of the patient. CONCLUSIONS: We envisage such a test having a role in assessing bed-bound patients in hospital where access to formal visual field testing is difficult, or indeed in rapid testing of visual fields at the bedside to screen for post-operative complications, such as haematoma.

Volumetric growth rates of meningioma and its correlation with histological diagnosis and clinical outcome: a systematic review.

INTRODUCTION: Tumour growth has been used to successfully predict progression-free survival in low-grade glioma. This systematic review sought to establish the evidence base regarding the correlation of volumetric growth rates with histological diagnosis and potential to predict clinical outcome in patients with meningioma. METHODS: This systematic review was conducted according to the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. Databases were searched for full text English articles analysing volumetric growth rates in patients with a meningioma. RESULTS: Four retrospective cohort studies were accepted, demonstrating limited evidence of significantly different tumour doubling rates and shapes of growth curves between benign and atypical meningiomas. Heterogeneity of patient characteristics and timing of volumetric assessment, both pre- and post-operatively, limited pooled analysis of the data. No studies performed statistical analysis to demonstrate the clinical utility of growth rates in predicting clinical outcome. CONCLUSION: This systematic review provides limited evidence in support of the use of volumetric growth rates in meningioma to predict histological diagnosis and clinical outcome to guide future monitoring and treatment.

Correlation of volumetric growth and histological grade in 50 meningiomas.

INTRODUCTION: Advances in radiological imaging techniques have enabled volumetric measurements of meningiomas to be easily monitored using serial imaging scans. There is limited literature on the relationship between tumour growth rates and the WHO classification of meningiomas despite tumour growth being a major determinant of type and timing of intervention. Volumetric growth has been successfully used to assess growth of low-grade glioma; however, there is limited information on the volumetric growth rate (VGR) of meningiomas. This study aimed to determine the reliability of VGR measurement in patients with meningioma, assess the relationship between VGR and 2016 WHO grading as well as clinical applicability of VGR in monitoring meningioma growth. METHODS: All histologically proven intracranial meningiomas that underwent resection in a single centre between April 2009 and April 2014 were reviewed and classified according to the 2016 edition of the Classification of the Tumours of the CNS. Only patients who had two pre-operative scans that were at least 3 months apart were included in the study. Two authors performed the volumetric measurements using the Slicer 3D software independently and the inter-rater reliability was assessed. Multiple regression analyses of factors affecting the VGR and VDE of meningiomas were performed using the R statistical software with p < 0.05 considered to be statistically significant. RESULTS: Of 548 patients who underwent resection of their meningiomas, 66 met the inclusion criteria. Sixteen cases met the exclusion criteria (NF2, spinal location, previous surgical or radiation treatment, significant intra-osseous component and poor quality imaging). Forty-two grade I and 8 grade II meningiomas were included in the analysis. The VGR was significantly higher for grade II meningiomas. Using receiver-operator characteristic (ROC) curve analysis, the optimal threshold that distinguishes between grade I and II meningiomas is 3 cm3/year. Higher histological grade, high initial tumour volume, MRI T2-signal hyperintensity and presence of oedema were found to be significant predictors of higher VGR. CONCLUSION: Reliable tools now exist to evaluate and monitor volumetric growth of meningiomas. Grade II meningiomas have significantly higher VGR compared with grade I meningiomas and growth of more than 3 cm3/year is strongly suggestive of a higher grade meningioma. A larger, multi-centre prospective study to investigate the applicability of velocity of growth to predict the outcome of patients with meningioma is warranted.

Methodological shortcomings in the literature evaluating the role and applications of 3D training for surgical trainees.

AIM: There has been an increased interest in the use of three-dimensional (3D) technology in surgical training. We wish to appraise the methodological rigor applied to evaluating the role and applications of 3D technology in surgical training, in particular, on the validity of these models and assessment methods in simulated surgical training. METHODS: Literature search was performed using MEDLINE with the following terms: "3D"; "surgery"; and "training". Only studies evaluating the role of 3D technology in surgical training were eligible for inclusion and assessed for the level of evidence, validity of the simulation model, and assessment method used. RESULTS: A total of 93 studies were analyzed, and majority of reviewed articles focused on 3D displays (36) and 3D printing (35). Most of these studies were case series, the most common assessment was subjective (69), with objective assessment used by 57 studies. Very few studies provided evidence for validity of the model or the assessment methods used. CONCLUSIONS: 3D technology has a great potential in simulated surgical training. However, the validity of this technology and strong evidence for its beneficial effects in surgical training is lacking. Further work on validation of 3D technology and assessment tools is needed.

Bicoronal frontobasal approach with a limited, midline orbital bar osteotomy - a technical note.

The frontobasal approach remains a workhorse for removing large olfactory groove meningiomas. Removal of the orbital bar in addition to standard bifrontal craniotomy allows for additional basal exposure, minimising brain retraction and allowing early and direct access to both the vascular supply and dural origin of this tumour. Here, we describe a simple yet effective modification to the standard orbital bar osteotomy. It has the benefit of being simpler and faster with improved cosmesis compared with an osteotomy of the entire orbital bar. It also has the advantage of not requiring manipulation of the supraorbital nerves or intraorbital or periorbital dissection.

Outcome of microsurgical excision of unruptured brain arteriovenous malformations in ARUBA-eligible patients.

OBJECTIVES: To determine the outcome of microsurgical excision of selected unruptured brain arteriovenous malformations (AVMs), and to compare the results with those of the ARUBA trial. METHODS: Prospective data collection for all patients undergoing microsurgical excision of unruptured brain AVMs by two neurovascular surgeons. Outcome measures similar to those assessed in the ARUBA trial (death and stroke) as well as modified Rankin scores (mRS) at 6 months were assessed. RESULTS: Between September 2004 and September 2014, 45 patients with unruptured brain AVMs underwent microsurgical excision. 11 patients (eight children and three with mRS >2 at presentation) were excluded to match ARUBA eligibility criteria. 34 patients were included in this study. AVM characteristics closely matched those in the ARUBA trial with 70.5% Spetzler-Martin (SM) grade I or II AVMs, 68% AVM size <3 cm. However, compared to ARUBA, a larger proportion of our patients presented with seizures, and a lower proportion with headaches. 8(23%) had preoperative embolization. There were no deaths and no strokes (as defined in ARUBA). 5 (14.7%) had permanent neurological deficit related to surgery within/near eloquent cortex. At 6 months follow-up, 32 (94%) had mRS score of 0-1. Two (6%) had mRS 2 and none had mRS> 2. Postoperative digital DSA confirmed complete AVM excision in all cases. None of the patients have suffered intracranial hemorrhage during the follow-up period of 6-126 (median 69) months. CONCLUSIONS: Microsurgical excision of unruptured brain AVMs can be performed with low morbidity in selected cases. Our study has limitations particularly the small number of patients with selected AVMs for microsurgical excision. However, our results suggest that ARUBA results may not be applicable to microsurgical excision when cases are appropriately selected for this treatment modality.

The impact of major trauma centre implementation on the pathways and outcome of traumatic intracranial extradural haematoma in a regional centre.

INTRODUCTION: A new trauma care system with regional major trauma centres (MTC) was implemented on 1st April 2012 across England. We aimed to assess whether this has affected the referral pathways and mortality of patients undergoing emergency craniotomy for extradural haematoma (EDH), where clinical outcome is correlated with the time to intervention. MATERIALS AND METHODS: This was a retrospective cohort comparison study. All patients who had undergone evacuation of EDH from January 2011 to December 2013 were identified. Only those in whom a decision for emergency craniotomy had been made at the time of referral to the on-call neurosurgeon were included. The CRASH predicted risk of mortality was calculated for individual patients. Mortality was assessed at 14 days in order to compute standardised mortality ratios (SMR). RESULTS: Overall, 65 patients underwent EDH evacuation during the study period (21 pre-MTC and 44 post-MTC). Of those, 43 emergency procedures according to the aforementioned definition were included for further analysis (13 pre-MTC, 30 post-MTC). The mean CRASH predicted risk of mortality was 0.21 for the pre-MTC cohort (95% CI: 0.07-0.34) and 0.094 for the post-MTC cohort (95% CI: 0.039-0.15; p = 0.052). There was no significant difference in the rate of secondary transfers before and after MTC implementation (9/13 vs. 23/30, p = 0.71). The mean interval from referral to operation was 198 min for the pre-MTC cohort (95% CI: 123-273) and 201 min for the post-MTC cohort (95% CI: 141-262; p = 0.95). The SMR was 0.37 for the pre-MTC cohort (95% CI: 0.02-1.81; 1 death) and 0.71 for the post-MTC cohort (95% CI: 0.12-2.34; 2 deaths). CONCLUSIONS: MTC implementation has not affected the time to operation or the mortality following EDH evacuation.