bluuebunny/crossref_metadata_2025 huggingface dataset:
Le conflit invisible des identités dans les communautés résidentielles en Chine
Authors: Wang Yun , Cheng Wei Jin , Ye Dan
Published: December 2021

Il y a un conflit invisible d’identités entre propriétaires et locataires en Chine. En complément de la recherche positiviste, une sociologie à la fois empirique et compréhensive inspirée par Gilbert Durand permet d’interpréter ce fait comme un processus de construction sociale. L’ordre totalitaire imposant une vie normative en Chine a produit un double paradoxe : en se divisant en deux groupes, les habitants agissent selon une même logique sociale problématique. C’est donc un stigmate invisible, ou alors la base sociétale du stigmate, qui constitue l’arrière-plan de ce conflit invisible des identités. C’est en référence à la capacité imaginaire que l’on peut évoquer la forme nocturne de l’imaginaire comme issue à ce problème.
Art and Experience
Authors: Manfreda Luigi A.
Published: December 2021

Notre réflexion a pour but d’analyser certains aspects de l’art du XX e  siècle à partir des transformations que l’expérience du monde a éprouvées pendant l’époque contemporaine. Comme l’ont bien illustré dans leurs œuvres Simmel et Benjamin, l’idée même d’expérience a subi une crise profonde, conjointement à la crise du quotidien que l’Occident a connue en raison du progrès technologique. L’art du XX e  siècle tente de répondre à cette crise en se tournant d’une part vers la recherche de l’ immédiat , d’autre part vers une réappropriation, à travers un travail artistique conscient, du faire au sens propre du terme.
Numerical study of the Serre-Green-Naghdi equations and a fully dispersive counterpart
Authors: Duchêne Vincent , Klein Christian
Published: December 2021

We perform numerical experiments on the Serre-Green-Naghdi (SGN) equations and a fully dispersive "Whitham-Green-Naghdi" (WGN) counterpart in dimension 1. In particular, solitary wave solutions of the WGN equations are constructed and their stability, along with the explicit ones of the SGN equations, is studied. Additionally, the emergence of modulated oscillations and the possibility of a blow-up of solutions in various situations is investigated.

We argue that a simple numerical scheme based on a Fourier spectral method combined with the Krylov subspace iterative technique GMRES to address the elliptic problem and a fourth order explicit Runge-Kutta scheme in time allows to address efficiently even computationally challenging problems.
Analytical reconstruction formula with efficient implementation for a modality of Compton scattering tomography with translational geometry
Authors: Tarpau Cécilia , Cebeiro Javier , Rollet Geneviève , Nguyen Maï K. , Dumas Laurent
Published: December 2021

In this paper, we address an alternative formulation for the exact inverse formula of the Radon transform on circle arcs arising in a modality of Compton Scattering Tomography in translational geometry proposed by Webber and Miller (Inverse Problems (36)2, 025007, 2020). The original study proposes a first method of reconstruction, using the theory of Volterra integral equations. The numerical realization of such a type of inverse formula may exhibit some difficulties, mainly due to stability issues. Here, we provide a suitable formulation for exact inversion that can be straightforwardly implemented in the Fourier domain. Simulations are carried out to illustrate the efficiency of the proposed reconstruction algorithm.
Analysis on the influence of retailer's introduction of store brand under manufacturer's product line strategy
Authors: Jiao Yuanyuan , Li Yuhang , Du Jun
Published: December 2021

As the introduction of store brand (SB) by retailers becomes more common, national brand manufacturers (NBM) in the market often respond with a product line strategy. Then how should retailers decide their product lines under the situation that NBM adopt product line strategy? Under the manufacturer's product line strategy, this paper compares and analyzes three competitive strategies for retailers to introduce high-end SB, low-end SB and SB product line. The results show that: First, no matter what kind of competition strategy the retailer adopts, (1) the introduction of SB occupies the market share of NB; (2) the retailer gains the highest unit income from the high-end products of NB manufacturers. Second, the relationship between production cost and encroachment effects directly affects the retailer's choice of optimal competitive strategy and the manufacturer's preference for its competitive strategy choice. Finally, from the perspective of profit maximization, the optimal choice for retailers is the product line competition strategy, but this strategy is not obvious compared with the high-end competition strategy. Therefore, when retailers introduce product lines, if they are effectively threatened by national brand manufacturers (for example, NBM refuses to provide national brands to retailers), retailers may choose the suboptimal strategy, that is, to introduce store brand high-end products. When the high-end products of store brands are better than the low-end products of national brands and the production cost of products is relatively high, this strategy just meets the expectations of national brand manufacturers for retailers to introduce strategies.
Some families of differential equations associated with the Gould-Hopper-Frobenius-Genocchi polynomials
Authors: Alyusof Rabab , Jeelani Mdi Begum
Published: December 2021

The basic objective of this paper is to utilize the factorization technique method to derive several properties such as, shift operators, recurrence relation, differential, integro-differential, partial differential expressions for Gould-Hopper-Frobenius-Genocchi polynomials, which can be utilized to tackle some new issues in different areas of science and innovation.
Exploring the role of eRNA in regulating gene expression
Authors: Tan Heli ,   School of Financial Mathematics and Statistics, Guangdong University of Finance, Guangzhou 510521, China, Liu Tuoqi , Zhou Tianshou ,   School of Mathematics, Sun Yat-Sen University, Guangzhou 510275, China,   Guangdong Province Key Laboratory of Computational Science, Guangzhou 510275, China
Published: December 2021

eRNAs as the products of enhancers can regulate gene expression via various possible ways, but which regulation way is more reasonable is debatable in biology, and in particular, how eRNAs impact gene expression remains unclear. Here we introduce a mechanistic model of gene expression to address these issues. This model considers three possible regulation ways of eRNA: Type-I by which eRNA regulates transcriptional activity by facilitating the formation of enhancer-promoter (E-P) loop, Type-II by which eRNA directly promotes the mRNA production rate, and mixed regulation (i.e., the combination of Type-I and Type-II). We show that with the increase of the E-P loop length, mRNA distribution can transition from unimodality to bimodality or vice versa in all the three regulation cases. However, in contrast to the other two regulations, Type-II regulation can lead to the highest mean mRNA level and the lowest mRNA noise, independent of the E-P loop length. These results would not only reveal the essential mechanism of how eRNA regulates gene expression, but also imply a new mechanism for phenotypic switching, namely the E-P loop can induce phenotypic switching.
Mechanical stress induces a scalable circularly polarized LEO satellite antenna with Quadrifilar spiral
Authors: Shen Jie ,   State Grid Jibei Zhangjiakou Wind and Solar Energy Storage and Transportation New Energy Co., Ltd, China, Liu Han-min , Wang Jing ,   Hebei Province Wind and Solar Energy Storage Combined Power Generation Technology Innovation Center, China,   Beijing University of Posts & Telecom, Beijing 100876, China
Published: December 2021

This paper investigates a left-hand circularly polarized (LHCP) antenna and a right-hand circularly polarized (RHCP) antenna on LEO Satellite, which is based on the phase-tuning metasurface. We overcome its inherent limitations in size, weight and power, and designed a high-gain, ultra-lightweight, scalable antenna for small satellite communications. The antenna can generate continuous and large tunability of subwavelength, with low-Q resonators. The simulated and experimental results verify that different capacitance and inductance modes can be effectively generated by rotating the spiral arms of single-arm spiral antennas with corresponding degrees, which greatly simplify the feeding network. The maximum gain of the normal position within the angle of the uplink and downlink is 4~9 dBi higher than that of the ordinary polarized antenna. In addition, the design method proposed to this article is superior to the reference system in terms of impedance bandwidth, axial ratio bandwidth, and operation frequency. The performance achievements of this paper are implemented within the bandwidth of 3 MHz of uplink and downlink, such as impedance bandwidth is 3 MHz with impedance of 50, axial ratio bandwidth is 2.5 MHz, operation frequency of uplink is 240–243 MHz, downlink is 320 MHz and 401 MHz, and the voltage standing wave ratio (VSWR) is less than 2 dB which is so called S parameter, the above parameters can meet the performance index design requirements.
Subjects Who Cannot Be Consoled: The Discarded Opening of Albert Angelo and the Queer Afterlife of “BS” Johnson in We Are Made of Diamond Stuff by Isabel Waidner
Authors: Clarke Chris
Published: December 2021

In the discarded opening section of Albert Angelo (1964), recovered by Jonathan Coe in his biography of B. S. Johnson, the narrator laments how “God had made another ballsup”: the protagonist’s “other half” is “almost a man instead of wholly a woman”. This essay reads Johnson’s abandoned representation of same-sex desire through the “tradition of queer backwardness” traced by Heather Love in Feeling Backward: Loss and the Politics of Queer History (2007). I argue that the abandoned fragment’s representation of “an unspeakable, inexplicable knowing” between two characters evokes the “backward feelings” which Love proposes are tied to “the historical ‘impossibility’ of same-sex desire” (Love 2007). In doing so, I show how Johnson’s literary afterlife lies in orientating readers to modernity’s denigrated “others”, such as sexual deviants marginalized for refusing to take what Johnson calls the “normal way”. Where the backward feelings in Johnson’s experimental novel illuminate his work’s resistance to various conditions of modern subjecthood, they can equally help us understand the resonance between his work and recent innovative fiction, which also contests punitive forms of social normalization. Isabel Waidner’s “critically British novel”, We Are Made of Diamond Stuff (2019), for example, reanimates Johnson’s perverse character “House Mother Normal” to propel its critique of the inequities of class, queerness, and national identity. We can appreciate what remains most subversive about Johnson’s experimental novels by charting how their backwardness reverberates with the concerns of queer experimental literature in the present.
“I’m telling you to stop’: Staging the drama of rape, experiment and sexual consent in Ann Quin’s Three and Muriel Spark’s The Driver’s Seat
Authors: Osborne Nell
Published: December 2021

This article considers experimental literary strategies alongside depictions of male sexual violence in work by two British women writers: The Driver’s Seat by Muriel Spark (1970) and Three by Ann Quin (1966). It reframes these novels’ particular interest in staging the drama of rape as literary experiment alongside the feminist struggle to articulate and theorise women’s restricted agency in the context of sexuality. I consider how violent avant-garde aesthetic convention is negotiated through emerging feminist anxieties and meditations on sexual violence and gender in these texts. I will suggest that sexual consent emerges as a paradoxically useful site through which women’s contingent and often precarious status as free and equal subjects is revealed. By staging narrative, temporal and affective experiment into the legal and cultural judgments that establish sexual consent, Spark and Quin deploy a modified aesthetics of shock and transgression, which helps to disclose the discursive limitations of both female agency and victimhood.
Getting it All Down: Disintegration and Integration in B. S. Johnson’s The Unfortunates
Authors: Winsworth Ben
Published: December 2021

B. S. Johnson’s infamous ‘book in a box’ The Unfortunates (1969) is more than an experiment in form. The unbound signatures of the novel we are invited to shuffle into any order before reading are not only expressive of Johnson’s belief in the random nature of existence, but more specifically, as his friend Zulfikar Ghose noted, the randomness that is in the nature of cancer. The box of tricks aspect to the novel has often occluded the human story contained within it: the death of the narrator’s/Johnson’s friend Tony from cancer, and his attempt to fulfil his final promise to ‘get it all down mate’ and so write with unflinching honesty about the experience and its aftermath. Critics have either tended to dismiss the story of the lives contained within The Unfortunates as mundane and boring, or as failing to match up to the radical format of the text. However, in this article I will be reconsidering the relationship between form and content, arguing that the narrator’s melancholy observation of life and descriptions of the slow and painful death of his friend are more than an adequate match for the structure/non-structure of the novel. Tony’s physical disintegration and the narrator’s depressive state of mind, as he reflects back upon the death of his friend and its consequences, find an ideal habitat in the fragmentary nature of The Unfortunates. I will also be attempting to show how the more formal, physical aspects of the novel — the box, the first and final part, the unnumbered signatures — facilitate the dynamics of grief in providing a space for Johnson’s interior monologues to take whatever experimental shape and direction they choose, while also working to hold and contain the emotional and intellectual conflicts within them and thus guard against complete disintegration. I shall be arguing that within this particular interplay there is a movement towards integration that, while it doesn’t give Johnson any wholly positive insights, is at the very least a gesture towards the therapeutic for both himself and the reader.
Chemical Fertilizer Imports and the Environment: Evidence-based Approach for a Green Economy Accounting for the Tradeoff
Authors: Wijesinghe A.
Published: December 2021

The direct and indirect impact of high-input use agriculture- popularised by the Green Revolution- on the environment is the major thrust of this perspective. The paper discusses an integrated approach to minimise the negative impacts, accounting for the proposed ban of synthetic fertilizers and the tradeoff between the environment and productivity resulting from such a ban. Noteworthy stylised facts of the discussion are threefold. First, the Green Revolution reduced the growth of extensive expansion of agricultural lands via intensification, which subdued the pressure on forest cover. Additionally, productivity increase releases marginal lands for vital ecological services such as pollinator habitats. Second, synthetic fertilizer resulted in higher productivity in the agriculture sector, increasing the GDP and facilitating structural transformation. Given that a quarter of the workforce is in the agriculture sector, gradual movement of the labor force to the industrial sector is vital, while the agriculture sector workforce become self-reliant in facing environmental and climatic events. Thus, continuous investment in agricultural productivity growth should be a priority to create fiscal space for the investments in meaningful green initiatives and reduce the vulnerability of the rural poor. Third, evidence-based solutions such as site-specific fertilizer recommendations, soil testing, and discouraging overuse of nitrogenous fertilizer through tariffs should be practised to mitigate the adverse environmental impact of synthetic fertilizer, especially nitrogen fertilizer. Complete removal of the subsidy may generate overreaching welfare and environmental ramifications, although it is widely suggested.
Improvement of atopic dermatitis and alopecia universalis with dupilumab: a case report
Authors: Alotaibi Lama , Alfawzan Abdulrahman , Alharthi Raghad , Al sheikh Afaf
Published: December 2021

Dupilumab is an interleukin (IL)-4 receptor alpha antagonist that showed significant improvement of atopic dermatitis (AD). Many reports have shown significant resolution of alopecia areata, alopecia universalis, and alopecia totalis after dupilumab treatment for AD. We present one of the few reported cases that showed improvement of underlying alopecia universalis treated with dupilumab.
Fibrinogenolytic activity of protease from the culture fluid of Pleurotus ostreatus
Authors: Stohnii Yevhenii M. , Sakovich Valeriia V. , Chernyshenko Volodymyr O. , Chernishov Volodymyr I. , Chernyshenko Tamara M. , Kolesnikova Iryna , Kucheriavyi Yevhenii P. , Zhernossekov Dmitrii D.
Published: December 2021

The use of proteases makes it possible to obtain partially hydrolyzed forms of macromolecules with unique properties. The importance of proteases for studying the structure and functions of fibrinogen forces scientists to search for new sources of highly specific proteases. Thus, the aim of this work was to study the content of the Pleurotus ostreatus culture fluid in search of fibrinogen- specific proteases. P. ostreatus was cultured for 14 days at 27°C. The culture fluid was collected and the protein fraction was salted out with NaCl and then dialyzed. Fibrinogen hydrolysis products by P. ostreatus protease were characterized using SDS PAGE under reducing conditions followed by immunoprobing using murine monoclonal antibodies I-5A (anti-Aα505-610) and 2d2a (anti-Bβ26-42). The study of turbidity and platelet aggregation was performed using a Multiskan FC spectrophotometric microplate reader and a SOLAR-2110 aggregometer, respectively. Electron microscopy of fibrils formed by truncated compared with native fibrins was performed using a transmission electron microscope N-600.

Analysis of the products of fibrinogen hydrolysis with a fungal protease using SDS-PAGE demonstrated the cleavage of the alpha chain of fibrinogen exclusively with the formation of a truncated form of fibrinogen in which there are no C-terminal portions of αC regions with a molecular weight of 25 kDa. A study of turbidity showed that the polymerization of truncated fibrin is significantly impaired. The rate of lateral association of protofibrils significantly decreased from 1.5 to 2.2 times in the case of truncated fibrinogen compared to the native one depending on the initial concentration of fibrinogen. It was shown that platelet aggregation in the presence of fibrinogen without 25 kDa fragments of αC regions was less effective than in the presence of native fibrinogen. Application of the preparation of the fungal protease allows us to obtain high molecular forms of the fibrinogen molecule with cleaved 25 kDa peptides, which provide new information on the role of these peptides in the fibrinogen functioning.
A Questionnaire-based Survey of Clinical Neuro-oncological Practice in India
Authors: Madhugiri Venkatesh S , Moiyadi Aliasgar , Nagella Amrutha Bindu , Singh Vikram , Shetty Prakash
Published: December 2021

Background:

Neuro-oncology is a relatively young subspecialty of neurosurgery. 2018 was the 10th year since the founding of the Indian Society of Neuro-oncology.

Objective:

To assess patterns in neuro-oncology practice in India.

Methods:

This was an online survey covering various domains of neuro-oncology such as demographics and practice setting, protocols for the medical management of patients with brain tumors, protocols for surgery and the perioperative period (including antibiotic prophylaxis, dural closure techniques, etc.), technological adjuncts used for brain/spine tumors (including intraoperative neurologic monitoring-IONM), and management protocols for certain specific clinical scenarios.

Results:

The response rate was 13%. Although 37% of the respondents' institutions could be considered as having reasonable surgical volumes (>1 procedure/day), only about half of these had high volumes of malignant brain tumor surgery. A wide variation was seen in medical management, perioperative protocols, use of adjuncts and intraoperative technologies, and paradigms for specific clinical scenarios.

Conclusions:

There is a need to standardize the protocols in neuro-oncology. This could be achieved by strengthening the formal training process in surgical neuro-oncology.
Mechanical Thrombectomy in Embolic Cardiac Myxoma
Authors: Bhatia Vikas , Jain Chirag , Ray Sucharita , Gupta Ojas , Chatterjee Debajyoti , Kumar Ajay
Published: December 2021

Myxomas are the most common cardiac tumors and present clinically with cardiac manifestations, systemic constitutional symptoms, and embolic events. Posterior circulation involvement occurs in approximately 20 percent of cerebral ischemic events. The endovascular technique is an established life-saving therapy for eligible patients upto 24 hours from symptom onset. However, the role of endovascular management in embolic atrial myxoma remains unknown with no international consensus guidelines for the management of stroke in such patient population. Here, we present a case report of an embolic posterior circulation stroke in a young female treated with mechanical thrombectomy at 23 hours from symptom onset. To the best of our knowledge, this is the first thrombectomy case in posterior circulation with embolism from myxoma. Further workup confirmed an atrial myxoma which was resected. We also review the previous cases with mechanical thrombectomy done in such cases.
Microsurgical Embolectomy in the Current Era of Pharmacological and Mechanical (Endovascular) Thrombolysis—A Reappraisal
Authors: Rajeev Sharma , Katsumi Takizawa
Published: December 2021

Introduction:

Microsurgical embolectomy though is the oldest known recanalization technique is being dismissed in favor of the latest mechanical endovascular techniques for the management of acute large vessel occlusion.

Aim and Objective:

We aim to highlight the role of microsurgical embolectomy in the current era of pharmacological and mechanical (endovascular) thrombolysis.

Methods:

An outline of the microsurgical embolectomy technique is described along with its current indications, advantages, and disadvantages.

Results:

It carries higher complete (TICI 3) revascularization rates with lower risk of distal embolic events especially in cases with high clot burdens; but is more labor-intensive and has longer reperfusion time in comparison to endovascular methods along with the requirement of highly skilled neurovascular surgeons to perform it quickly.

Conclusion:

Microsurgical embolectomy is an important indispensable recanalization technique in the armamentarium of vascular neurosurgeons.
Outcome Following Surgical Revascularization in Patients of Moyamoya Disease with Focus on Graft Patency and Angiographic Changes
Authors: Gupta Sunil K , Narayanan Rajashekhar , Aggarwal Ashish , Mohanty Manju , Ahuja Chirag , Verma Nidhi , Praneeth Kokkula , Agarwal Vivek
Published: December 2021

Background:

Surgical revascularization is the mainstay of treatment in symptomatic patients of moyamoya disease (MMD).

Objective:

The present study analyzed the postoperative angio-architecture in pediatric and adult patients of moyamoya disease.

Material and Methods:

Patients with MMD, both ischemic and hemorrhagic, were subjected to surgery. A superficial temporal artery-middle cerebral artery (STA-MCA) anastomosis was attempted in all. It was augmented by an encephalo-duro-myo-synangiosis), this was labelled as the combined surgical group. In patients where a direct bypass was not possible encephalo-duro-arterio-myo-synangiosis (EDAMS) was performed and these patients were put in the indirect surgery group. In the postoperative period, MRA was performed in all patients to look for (a) graft patency, (b) regression of moyamoya vessels, and (c) degree of surgical neovascularization (as quantified on adapted Matsushima and Inaba grading system).

Results:

Eighty-two patients underwent 131 surgical revascularization procedures. A combined surgery (STA-MCA bypass and EDAMS) was performed in 100 hemispheres and indirect surgery (EDAMS) on 31 sides. In children less than 5 years of age, STA-MCA anastomosis was possible in more than 50% of patients. Clinical improvement was seen in 85.4% of patients. Postoperative MRA demonstrated a patent bypass graft in 97% of cases. Regression of moyamoya vessels was seen in half of the cases and good surgical revascularization (type A and B) was seen in more than 80% of hemispheres in the combined surgery and indirect surgery group.

Conclusions:

Revascularization procedures led to a regression of moyamoya collaterals, appearance of surgical neo angiogenesis, and a graft patency rate of 97%. Surgical group with combined revascularization had a trend towards better collateral development.
Pediatric to Adult Hydrocephalus
Authors: Hong Manilyn A , Sukumaran Arvind , Riva-Cambrin Jay
Published: December 2021

Introduction:

Pediatric patients treated for hydrocephalus, regardless of etiology, require continuous access to care to address the long-term sequelae from the disease progression itself and from the interventions undertaken. The challenge for all pediatric neurosurgeons is providing comprehensive and coordinated care for these patients in order to achieve a smooth and seamless transition into adult health care.

Methods:

A review of the literature was conducted regarding the overall concept of pediatric patients with chronic conditions transitioning to adult care. We also specifically reviewed the pediatric hydrocephalus literature to investigate the barriers of transition, models of success, and specific elements required in a transition policy.

Results:

The review identified several barriers that hamper smooth and successful transition from pediatric to adult care within the hydrocephalus population. These included patient-related, cultural/society-related, healthcare provider-related, and healthcare system-related barriers. Six elements for successful transitions were noted: transition policy, tracking and monitoring, transition readiness, transition planning, transfer of care, and transition completion stemming from the Got Transition center.

Conclusions:

A successful patient transition from pediatric neurosurgical care to adult neurosurgical care is very center-specific and depends on the available resources within that center's hospital, health system, and geo-economic environment. Six recommendations are made for transition policy implementation in resource-poor environments, including beginning the process early, preferably at age 14 years.
Genetics and Molecular Pathogenesis of Human Hydrocephalus
Authors: Garcia-Bonilla Maria , McAllister James P , Limbrick D Limbrick
Published: December 2021

Hydrocephalus is a neurological disorder with an incidence of 80–125 per 100,000 live births in the United States. The molecular pathogenesis of this multidimensional disorder is complex and has both genetic and environmental influences. This review aims to discuss the genetic and molecular alterations described in human hydrocephalus, from well-characterized, heritable forms of hydrocephalus (e.g., X-linked hydrocephalus from L1CAM variants) to those affecting cilia motility and other complex pathologies such as neural tube defects and Dandy–Walker syndrome. Ventricular zone disruption is one key pattern among congenital and acquired forms of hydrocephalus, with abnormalities in cadherins, which mediate neuroepithelium/ependymal cell junctions and contribute to the pathogenesis and severity of the disease. Given the relationship between hydrocephalus pathogenesis and neurodevelopment, future research should elucidate the genetic and molecular mechanisms that regulate ventricular zone integrity and stem cell biology.
Mathematical Modelling in Hydrocephalus
Authors: Kazimierska Agnieszka , Ziółkowski Arkadiusz , Kasprowicz Magdalena , Lalou Afroditi , Czosnyka Zofia , Czosnyka Marek
Published: December 2021

Background:

Various studies highlight the significance of alterations in cerebrospinal fluid (CSF) and cerebral blood flow (CBF) dynamics in the pathogenesis of hydrocephalus and suggest the role of mathematical modeling in studying these complex interactions.

Objective:

This narrative review discusses mathematical models of CSF and CBF dynamics, including Marmarou's compartmental model of CSF spaces and a model of cardiac changes in cerebral arterial blood volume. The diagnostic utility of CSF compensatory parameters is described along with current information on secondary model-based indices of cerebral hemodynamics in hydrocephalus.

Conclusions:

Compensatory parameters derived from the model of CSF circulation have long been used in the diagnosis and management of hydrocephalus patients. However, recent studies using mathematical models of cerebral circulation also show alterations in CBF dynamics, and model-based indices of cerebral hemodynamics, which can be calculated non-invasively using transracranial Doppler ultrasonography, can be used as a complementary source of information about the state of the cerebrospinal space.
Evaluation and Management of Patients with Hydrocephalus in Craniosynostosis
Authors: Grant Jaime , Jagadeesan Jagajeevan , Gallo Pasquale , Rodrigues Desiderio
Published: December 2021

Background:

Hydrocephalus in presence of craniosynostosis, though relatively rare, occurs in 4%–10% cases, with an increased incidence in syndromic craniosynostosis. The optimum management in these patients is unknown.

Materials and Methods:

A search was performed on the departmental craniofacial database to identify all patients with craniosynostosis and hydrocephalus from January 2000 to December 2020. Diagnosis was confirmed by a meticulous review of the notes and previous imaging. These patients were grouped into two groups based on the primary treatment they received: either a cerebrospinal fluid (CSF) diversion procedure or a calvarial remodeling procedure. By analyzing the outcomes for each group, we endeavor to rationalize and outline our management strategy for this complex cohort of patients.

Results:

Sixty-four of 989 patients were confirmed to have hydrocephalus. Of these, 55 patients underwent calvarial expansion while nine had CSF diversion as a primary procedure. Our study demonstrates that the complication rate is lower in the primary calvarial expansion group. Furthermore, the need for a CSF diversion procedure was avoided in a significant number of these patients as a direct result.

Conclusion:

In the vast majority of patients with craniosynostosis and hydrocephalus, calvarial expansion surgery should be the preferred primary management option.
Idiopathic Intracranial Hypertension - Challenges and Pearls
Authors: Rohit Wadikhaye , Rajesh Alugolu , Mridula Rukmini , Jabeen Shaik A
Published: December 2021

Idiopathic intracranial hypertension (IIH) is defined as a syndrome of raised intracranial pressure with normal imaging of the brain and cerebrospinal fluid (CSF) composition. There is a rising incidence and prevalence of this disease related to the increased prevalence of obesity. It typically affects women of working age, and headache is the predominant morbidity in over 90%. The disease is also more prevalent in young males. There are many controversies and myths that surround IIH. There are currently few treatment options for IIH, management is typically medical with those experiencing progressive visual loss undergoing surgical procedures. Weight loss and venous sinus stenting are a few therapies directed at the etiology.
Prenatal Ventriculomegaly – Diagnosis, Prognostication and Management
Authors: Krishnan Vivek , Sharma Akshatha , Ramamurthy Rachita , Elayedatt Rinshi , Ramamurthy B S
Published: December 2021

Fetal ventriculomegaly (VM) refers to the abnormal enlargement of one or more ventricles of the brain in-utero. The enlargement may or may not be related to ventricular obstruction and increased intracranial pressure; therefore, the term “hydrocephalus” is not used. VM is diagnosed usually in the mid-trimester when the atrial diameter (AD) of the lateral ventricle is more than 10 mm on one or both sides. A thorough workup is then required to identify the cause as the etiology is diverse. Fetal magnetic resonance imaging (MRI) may yield additional information. Serial ultrasound follow-up would be required to assess its progression with advancing gestation. The prognosis and long-term outcomes greatly depend upon the etiology, the severity at diagnosis, progression, and associations. This article reviews the definitions, diagnosis, and workup of fetal VM, discusses follow-up protocols and prognosis, and examines the role of fetal therapy, including fetoscopic surgery in its prenatal management.
A comparison of Adult and Pediatric Hydrocephalus
Authors: Deopujari Chandrashekhar , Mohanty Chandan , Agrawal Harshal , Jain Sonal , Chawla Pawan
Published: December 2021

Hydrocephalus is a common clinical problem encountered in neurosurgical practice. With greater subspecialisation, pediatric neurosurgery has emerged as a special discipline in several countries. However, in the developing world, which inhabits a large pediatric population, a limited number of neurosurgeons manage all types of hydrocephalus across all ages. There are some essential differences in pediatric and adult hydrocephalus. The spectrum of hydrocephalus of dysgenetic origin in a neonate and that of normal pressure hydrocephalus of the old age has a completely different strategy of management. Endoscopic third ventriculostomy outcomes are known to be closely associated with age at presentation and surgery. Efficacy of alternative pathways of CSF absorption also differs according to age. Managing this disease in various age groups is challenging because of these differences in etiopathology, tempo of the disease, modalities of investigations and various treatment protocols as well as prognosis.
Management of Complex Hydrocephalus
Authors: Gabbita Abhirama Chandra , Raju Subodh
Published: December 2021

Background:

Management of complex/multiloculated/septated hydrocephalus is challenging. Neuroendoscopy has been well-established when compared to multiple shunt placements in management of multiloculated hydrocephalus (MH). The main aim of neuroendoscopy is to convert multiple locules into a single locule and drain it by either third ventriculostomy or ventriculoperitoneal shunt.

Objective:

The objective is to reduce the number of surgical procedures and improve the quality of life. Neuroendoscopy avoids multiple shunt placement and need for revision of shunt.

Methods:

Literature review regarding natural history, pathogenesis, classification and management of complex/uni/multiloculated hydrocephalus was extensively done and our minimal experience with these cases has been taken into consideration.

Conclusion:

Neuroendoscopy when combined with frameless neuronavigation is reliable, accurate, and extremely useful in maintaining orientation and localizing the appropriate fenestration site in MH where anatomical landmarks are grossly distorted.
Trans-Sylvian Resection of Giant Left Insular Glioma
Authors: Agrawal Rati , Arumulla Sivasai , Manjunath Nivedita , Meena Rajesh , Doddamani Ramesh , Singh Pankaj Kumar , Chandra Sarat P.
Published: December 2021

Background:

Insular glioma was considered a nonsurgical entity due to resection-associated morbidities. The advancement in neurosurgical techniques and adjuncts used in the last two decades made the resection of insular gliomas simpler for neurosurgeons with the maximum extent of resection and acceptable morbidity rates. The complex anatomy of this region remains a challenge for neurosurgeons and requires expertise. The key factors to achieve complete resection in the insular region are the thorough knowledge of surgical anatomy and meticulous microsurgical techniques. Intraoperative adjuncts such as image guidance along with cortical and subcortical mapping assist in excellent outcomes.

Objective:

In this study, we describe the operative technique and application of trans-Sylvian approach to do the compartmental dissection done by the senior author, along with challenges faced, with the hope to highlight the efficacy of the approach to achieve maximal resection of this entity without compromising patient's safety.

Materials and Methods:

A 32-year-old right-handed gentleman presented with episodes of excessive salivation, tingling sensation on the right side of the body along with nausea that lasted for 15–20 s for the last 8 months and one episode of speech arrest without any loss of consciousness and motor or sensory deficit. CEMRI of the brain was suggestive of left insular glioma. The patient underwent left pterional craniotomy, and gross total resection of the tumor was done using compartmental dissection.

Results:

At follow-up after 1 month, the patient is seizure-free without any speech difficulty and motor or sensory deficit.

Conclusion:

Compartmental dissection of insular glioma is a safe and efficacious technique to achieve gross total resection of the tumor in this complex region without morbidity.
Neuroendoscopy in the Surgical Management of Lateral and Third Ventricular Tumors
Authors: Deopujari Chandrashekhar E , Karmarkar Vikram S. , Shaikh Salman T. , Mohanty Chandan B. , Sharma Vikas , Tadghare Jitendra , Thareja Varun
Published: December 2021

Background:

Intraventricular tumors pose a surgical challenge because of the difficulty in reaching their deep location through safe corridors and their adherence or proximity to vital neurovascular structures. Although microneurosurgery is the mainstay of surgical management, neuroendoscopy aided by adjuncts, namely, navigation and ultrasonic aspirators, has made a great contribution to improving surgical results.

Objective:

This article reviews the experience of a neurosurgical unit with endoscopic procedures for intraventricular tumors. The current indications, benefits, and complications of neuroendoscopy are described.

Materials and Methods:

This is a retrospective, observational study of lateral and third ventricular tumors tackled either purely with an endoscope or with its assistance over 19 years in a single unit at Bombay Hospital Institute of Medical Sciences, Mumbai.

Results:

Of a total of 247 operated patients with intraventricular tumors, 85 cases operated using an endoscope were included. The majority of the patients had a tumor in the third ventricle (n = 62), whereas 23 patients had tumor in the lateral ventricle. The most common pathologies were colloid cyst and arachnoid cyst (n = 18). An endoscope was used for microsurgical assisted excision of tumors in 31 cases, biopsy in 24, cyst fenestration in 23, and pure endoscopic excision in seven cases.

Conclusion:

Microsurgery remains the gold standard for the removal of giant, vascular intraventricular tumors. However, endoscopic fenestration or excision of cysts and biopsy have become better alternatives in many cases. Endoscope-assisted microsurgery affords safety and helps in achieving a more complete excision.
Incidence of and Risk Factors for Emergence Delirium and Postoperative Delirium in Neurosurgical Patients- A Prospective Cohort Study
Authors: Bharadwaj Suparna , Kamath Sriganesh , Chakrabarti Dhritiman , Shetty Prajwal
Published: December 2021

Background:

Delirium after surgery is a spectrum of clinical syndrome constituting emergence delirium (ED) and/or postoperative delirium (POD).

Objectives:

The primary objective of this study was to evaluate the incidence of ED and POD in patients after neurosurgical procedures. The secondary objectives were to examine the relationship between ED and POD and identify perioperative risk factors of ED and POD.

Materials and Methods:

This is a prospective cohort study conducted at the National Institute of Mental Health and Neurosciences. After obtaining the ethics committee approval, consecutive adult patients scheduled for elective neurosurgical procedures from February 2018 to November 2018 were included. We excluded children, patients with preoperative Glasgow Coma score <15, and patients with preoperative delirium. ED was assessed using Riker's Sedation-Agitation Score and POD was assessed using Confusion Assessment Method. Data collection included patient demographics, details of anesthetics and analgesics, and neurosurgical details.

Results:

The incidence of ED and POD was 41% (N = 82/200) and 20% (N = 40/200), respectively. The occurrence of ED and POD coexisting as a continuous spectrum was 15%. Patients undergoing spine surgeries were found to have 44% less risk of ED than after cranial surgeries (P = 0.032). Presence of ED was associated with 1.8 times higher risk of POD (P < 0.001) and male gender was associated with 2.5 times higher risk of POD (P = 0.005).

Conclusions:

Incidences of ED and POD are higher after neurosurgery as compared with that reported in nonneurosurgical population previously.
Assessment of Collaterals Using Multiphasic CT Angiography in Acute Stroke
Authors: Adhithyan Rajendran , Kannath Santhosh , Thomas Bejoy , Jayadevan Enakshy , Sylaja PN , Kesavadas Chandrasekharan
Published: December 2021

Background and Purpose:

The aim of the research was to compare the efficiency of multiphase and single-phase computed tomography (CT) angiography in assessing the leptomeningeal collaterals and in predicting the long-term clinical outcome as well as the risk of hemorrhagic transformation.

Materials and Methods:

A prospective study was conducted from October 2016 to May 2018 in consecutive patients who presented within 8 hours of the onset of acute anterior circulation ischemic strokes, with NIHSS (National Institutes of Health Stroke Scale) scores ≥5. They underwent triple-phase cerebral CT angiography, and the collaterals were assessed separately using both single-phase and multiphase techniques. The ability of the collaterals to predict the 24-hour CT ASPECTS (Alberta Stroke Program Early CT score), risk of cerebral hemorrhagic transformation, and 90-day clinical outcome was assessed.

Results:

Fifty-six patients, which included 42 with an involvement of the middle cerebral artery and 14 with mixed occlusions, were assessed. In the multivariate logistic analysis, multiphase CT angiography collateral grading is one of the independent predictors of favorable outcomes. Area under the curve (AUC) was 0.853 (95% confidence interval [CI; 0.73, 0.97]) for multiphase CT collateral scoring in predicting the long-term functional independence, whereas single-phase CT (sCT) scoring displayed an AUC value of only 0.609 (95% CI [0.43, 0.78]). Eighty-two percent of the patients with good multiphase CT collaterals were functionally independent. CT ASPECTS at 24 hours was significantly better in patients with a good multiphase CT collateral score than in those with a good single-phase score. None of the patients with good collaterals in multiphase CT angiography had a significant hemorrhagic transformation. Good multiphase CT collaterals demonstrated 78% sensitivity, 81% specificity, and 80% accuracy in predicting the functional outcome.

Conclusion:

Multiphase CT collateral system was superior to single-phase angiography in predicting the long-term functional outcomes. Prediction of the hemorrhagic transformation risk was also observed to be better for multiphase CT.
Segmental Agenesis of External Carotid Artery from Common Carotid Artery with Anomalous Reformation through Occipital Artery Anastomoses
Authors: Furtado Sunil V , Quryshi Syed A , Jagannatha Aniruddha T , Hegde Alangar S
Published: December 2021

Anomalous origin of extracranial and intracranial carotid system is subject to permutations of embryonal regression of the developing primitive embryonal vasculature. We present a case of segmental agenesis of left external carotid artery from the cervical carotid circulation. The entire left external carotid artery was supplied by the vertebral artery through muscular branches via the occipital artery. This anomaly of proximal external carotid agenesis with the entire vascular tree dependent on the posterior circulation via occipital artery muscular collaterals is unique and has not been described before. We discuss this anomaly with its embryology, clinical implications, and its relationship to a Proatlantal artery.
Impact of Pre-Stroke Antiplatelet Use on 3-Month Outcome After Ischemic Stroke
Authors: Sylaja PN , Nair Sruthi S , Pandian Jeyaraj , Khurana Dheeraj , Srivastava M V Padma , Kaul Subhash , Arora Deepti , Sarma P Sankara , Singhal Aneesh B
Published: December 2021

Background:

Pre-stroke anti-platelet (PAP) therapy can potentially influence the severity and outcome after ischemic stroke.

Methods:

We analyzed data from the prospective multicenter Indo–US collaborative stroke project for the impact of PAP therapy. Outcome measures included the admission National Institute of Health Stroke Scale (NIHSS) score, 3-month modified Rankin scale (mRS) score, and rates of in-hospital mortality and post-ischemic intracerebral hemorrhage.

Results:

Among 2048 of 2066 patients (M:F = 2:1) with known pre-stroke medication status, 336 (16.3%) were on PAP therapy. As compared to the non-PAP group, the PAP group had significantly higher mean age (62.2 vs 57.4 years, P < 0.001) and significantly more men, vascular risk factors, cerebral microbleeds (12.8% vs 6.2%, P = 0.001) and intravenous thrombolysis treatment (17% vs. 10.6%, P = 0.001). Cardioembolic strokes were significantly more in the PAP group (P < 0.001), but not large artery atherosclerosis. No significant differences were observed in the median NIHSS score (9 vs. 10, P = 0.274), 3-month mRS (score 0-2,51.4% vs. 49.0%, P = 0.428), in-hospital mortality (8.6% vs. 7.8%, P = 0.592), or symptomatic post ischemic intracerebral haemorrhage (12.2% vs. 10.6%, P = 0.382). The PAP group had more stroke recurrence (6.6% vs. 2.9%, P = 0.002) which was not significant (P = 0.065) after multivariate regression analysis adjusting for age, sex and vascular risk factors. PAP therapy was not an independent predictor of initial stroke severity or stroke outcome.

Conclusion:

PAP therapy has no significant effect on initial stroke severity, rates of post-ischemic hemorrhage with or without thrombolysis, in-hospital mortality, stroke recurrence, and 3-month outcome after ischemic stroke.