Frequency and predictors of implant-related complications after posterior cervical fusion.

STUDY DESIGN: Retrospective, observational study. PURPOSE: To determine the frequency and predictors of implant-related complications in adults after posterior cervical fusion. OVERVIEW OF LITERATURE: Published literature on lumbosacral fusion suggest that implant-related complications are not uncommon. Although posterior cervical fusion is a common operation, data on frequency and predictors of implant-related complications after posterior cervical fusion is still scarce. METHODS: 86 patients (with 740 screws) who underwent posterior cervical fusion were included. Implant-related complications were identified by the presence of: (1) halo sign, (2) screw pull-out/breakage (3) post-operative kyphosis and (4) implant-related complications requiring revision surgery. These were stratified into two groups: (a) minor - isolated halo sign or screw pull-out/breakage (b) major - post-operative kyphosis > 10 degrees, and revision surgery. Demographic, operative and radiological data was collected. Rates of implant-related complications were determined and associated risk factors identified. RESULTS: 33 (38.4%) patients had signs of implant-related complications. Of these, 29 (87.9%) had minor complications and 4 (12.1%) had major complications. Charlson Comorbidity Index (CCI) (p = 0.03179) and pre-op C2-C7 sagittal vertical alignment (SVA) (p = 0.02449) were the only significant risk factors for all-cause implant-related complications during multivariate logistic regression. Other intraoperative parameters (type of screw, length of fusion, levels decompressed, and extension of fusion beyond the levels decompressed) were not significantly associated with implant-related complications. CONCLUSIONS: Implant-related complications are not uncommon but rarely require revision surgery. Higher pre-operative SVA and CCI were significant risk factors; length of construct and extent of decompression were not. These findings may assist clinicians when deciding the extent of fusion and in selecting patients for closer follow-up.

We assessed the frequency and predictors of implant-related complications in adults after posterior cervical fusion. Implant-related complications (halo sign, screw pull-out/breakage, post-operative kyphosis) are not uncommon but rarely require revision surgery. Higher pre-operative SVA and CCI were significant risk factors; length of construct and extent of decompression were not.

Blue-Green Infrastructure for Flood and Water Quality Management in Southeast Asia: Evidence and Knowledge Gaps.

In Southeast Asia, projections of rapid urban growth coupled with high water-related risks call for large investments in infrastructure-including in blue-green infrastructure (BGI) such as forests, parks, or vegetated engineered systems. However, most of the knowledge on BGI is produced in the global North, overlooking the diversity of urban contexts globally. Here, we review the literature on BGI for flood risk mitigation and water quality improvement in Southeast Asian cities to understand the scope of practical knowledge and identify research needs. We searched for evidence of local types of BGI in peer-reviewed and grey literature and assessed the performance of BGI based on hydrological, societal, and environmental metrics. The body of literature on BGI in Southeast Asia is small and dominated by wealthier countries but we found evidence of uptake among researchers and practitioners in most countries. Bioretention systems, constructed wetlands, and green cover received the most attention in research. Evidence from modelling and laboratory studies confirmed the potential for BGI to address flooding and water quality issues in the region. However, practical knowledge to mainstream the implementation of BGI remains limited, with insufficient primary hydrological data and information on societal and environmental impacts. In addition, the performance of BGI in combination with grey infrastructure, under climate change, or in informal settlements is poorly studied. Future research and practice should focus on producing and sharing empirical data, ultimately increasing the regional knowledge base to promote efficient BGI strategies.

The topology of ventricle surfaces and its application in the analysis of hydrocephalic ventricles: a proof-of-concept study.

PURPOSE: The cerebral ventricles deform in a non-uniform fashion in response to increased CSF volume and/or pressure in hydrocephalic syndromes. Current research is focused on volumetric analyses, while topological analysis of ventricular surfaces remains understudied. We developed a method of quantitatively modeling the curvature of ventricular surfaces to analyze changes in ventricular surfaces in normal pressure hydrocephalus (NPH) and Alzheimer's disease (AD), using the left frontal horn as an example. METHODS: Twenty-one patients with NPH were recruited from our institution, and 21 healthy controls (HC) and patients with Alzheimer's disease (AD) were identified from the Alzheimer's Disease Neuroimaging Initiative (ADNI) database. On T1-weighted fine-cut magnetic resonance sequences, 3D Slicer was used to segment the left frontal horn. Next, the mean curvatures at a set of points on the ventricular surface were determined. The frontal horns were scaled and centered into normalized volumes, allowing for pooling across the study subjects. The frontal horn was divided into superolateral, superomedial, inferolateral, and inferomedial surfaces, and locoregional mean curvatures were analyzed. Statistical comparisons were made between NPH, AD, and HC groups. RESULTS: Significant differences in the mean curvature of lateral surfaces of the ventricles distinguished patterns of distortion between all three cohorts. Significant flattening of the superomedial surface discriminated NPH from HC and AD. However, significant rounding of the inferomedial surface compared to controls was a distinguishing feature of NPH alone. CONCLUSION: NPH ventricles deform non-uniformly. The pattern of surface distortion may be used as an additional tool to differentiate between these hydrocephalic conditions.

Use of fluorescein sodium to obtain histological diagnosis of primary Central nervous system lymphoma ghost tumour despite disappearance on intraoperative magnetic resonance imaging: technical note and review of the literature.

BACKGROUND AND IMPORTANCE: Corticosteroid pre-treatment in patients with primary central nervous system lymphoma (PCNSL) can lead to the phenomenon of ghost tumours (GhT). This affects the diagnostic yield of biopsies and potentially causes misdiagnosis of the condition. The usual strategy of neuronavigation using preoperative magnetic resonance imaging (MRI) or localisation using intraoperative MRI (iMRI) can be rendered ineffective in this situation. CLINICAL PRESENTATION: A middle-aged Chinese male with newly diagnosed human immunodeficiency virus infection was found to have an intracranial lesion suggestive of PCNSL. Preoperatively corticosteroid led to an attenuation of the contrast enhancing lesion on iMRI. However, intraoperative use of FS allowed the successful identification, biopsy and diagnosis of the condition. CONCLUSION: FS is useful in the biopsy of PCNSL GhT even when the lesion is not seen in subsequent MRI imaging.

Practice enhancements with FastStroke ColorViz analysis in acute ischemic stroke.

In acute ischemic stroke (AIS), large vessel occlusion (LVO) and the status of pial collaterals are important factors in decision-making for further treatment such as endovascular therapy. Multiphasic CT Angiogram (mCTA) is the mainstay of AIS imaging, allowing detection of LVO, evaluation of intracranial arterial dynamics, and quantification of pial collaterals. However, thorough mCTA evaluation entails scrutiny of multiple image datasets, individually and then simultaneously, which can be time-consuming, causing a potential delay in treatment. ColorViz (FastStroke, GE Healthcare, Milwaukee, Wisconsin) is a novel CT application which combines mCTA information into a single color-coded dataset for quick, unequivocal evaluation of pial collaterals. In our practice, ColorViz is both time-saving and increases the diagnostic accuracy of LVO and pial collaterals as well as medium vessel, multivessel and posterior circulation occlusions. In this article, we discuss the practical aspects of ColorViz in patients presenting with AIS.

Microcatheter-Assisted Protection of the Posterior Inferior Cerebellar Artery During Parent Artery Sacrifice of a Vertebral Artery Dissecting Aneurysm.

Branch vessel occlusion is a major cause of stroke in parent artery sacrifice (PAS) for vertebral artery dissecting aneurysms (VADA). There is now an increasing trend towards preservation of branch vessels during PAS. Stents are commonly employed to achieve this but bring with it the attendant risks of future thrombosis and lifelong antiplatelet use. Although a microcatheter protection technique has been utilised in branch artery protection of wide-necked saccular aneurysms, it has rarely been described in PAS for VADAs. We describe the use of a dual microcatheter technique in the protection and remodelling of the posterior inferior cerebellar artery (PICA) during PAS of the vertebral artery, which also served as a temporary scaffold to support placement of the coils during the embolisation process.

Extraneural metastatic paediatric glioblastoma: Case report and literature review.

The incidence of paediatric glioblastoma is uncommon in comparison to their adult counterpart. Even more infrequent are extraneural metastases in glioblastoma. A previously well 14-year-old female presented with progressive right hemiparesis secondary to a left fronto-temporal lobe glioblastoma (WHO IV). She underwent successful gross total resection for her brain tumour. Prior to commencement of her adjuvant treatment, she developed tumour recurrence associated with intra-lesional haemorrhage. Although she underwent a second surgery, the patient developed bilateral malignant pleural effusion secondary to extraneural pulmonary metastases. Early awareness of its existence enables prompt diagnosis for this devastating disease. The authors emphasize the urgent need for international collaborations to work together for children affected by this challenging brain tumour.

When hoofbeats mean zebras not horses: Tumour mimics of subdural haematoma - Case series and literature review.

Chronic subdural haematomas are common neurosurgical conditions, especially in the elderly patients, with straightforward surgical treatments. However, infrequently, tumours are misdiagnosed as subdural haematoma on initial brain CT scans and are only discovered intraoperatively. In this case series, we presented 3 different patients who were initially thought to have subdural haematoma but later found to be tumour mimics of different histological origin. A literature review and discussion of recently published tumour mimics of subdural haematoma was also performed. It is recommended that in patients with suggestive oncological or haematological history, or unusual characteristics on the plain CT brain, a high level of suspicion of tumour mimics needs to be maintained. A full workup with contrast-enhanced magnetic resonance imaging is important to distinguish from subdural haematoma, as the treatment paradigms and prognoses are vastly different.