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Background: Performing transopercular frontal approaches to the insula, widely used in glioma surgeries, necessitates a meticulous understanding of both cortical and subcortical neuroanatomy. This precision is vital for preserving essential structures and accurately interpreting the results of direct electrical stimulation. Nevertheless, acquiring a compelling mental image of the anatomy of this region can be challenging due to several factors, among which stand out its complexity and the fact that white matter fasciculi are imperceptible to the naked eye in the living brain. Aim: In an effort to optimize the study of the anatomy relevant to this topic, we performed a procedure-guided laboratory study using subpial dissection, fiber dissection, vascular coloration, and stereoscopic photography in a "real-life" surgical perspective. Methods: Nine cerebral specimens obtained from body donation were extracted and fixed in formalin. Colored silicone injection and a variant of Klinglers's technique were used to demonstrate vascular and white matter structures, respectively. We dissected and photographed the specimens in a supero-antero-lateral view to reproduce the surgeon's viewpoint. The anatomy related to the development of the surgical corridor and resection cavity was documented using both standard photography and the red-cyan anaglyph technique. Results: The anatomy of frontal transopercular approaches to the insula involved elements of different natures—leptomeningeal, cortical, vascular, and fascicular—combining in the surgical field in a complex disposition. The disposition of these structures was successfully demonstrated through the aforementioned anatomical techniques. Among the main structures in or around the surgical corridor, the orbital, triangular, and opercular portions of the inferior frontal gyrus are critical landmarks in the cortical stage, as well as the leptomeninges of the Sylvian fissure and the M2–M4 branches of the middle cerebral artery in the subpial dissection stage, and the inferior fronto-occipital, uncinate and arcuate fasciculi, and the corona radiata in establishing the deep limits of resection. Conclusions: Procedure-guided study of cerebral hemispheres associating subpial, vascular, and fiber dissection from a surgical standpoint is a powerful tool for the realistic study of the surgical anatomy relevant to frontal transopercular approaches to the insula. [ABSTRACT FROM AUTHOR]

Traditional teaching methods struggle to convey three‐dimensional concepts effectively. While 3D virtual models and virtual reality platforms offer a promising approach to teaching anatomy, their cost and specialized equipment pose limitations, especially in disadvantaged areas. A simpler alternative is to use virtual 3D models displayed on regular screens, but they lack immersion, realism, and stereoscopic vision. To address these challenges, we developed an affordable method utilizing smartphone‐based 360° photogrammetry, virtual camera recording, and stereoscopic display (anaglyph or side‐by‐side technique). In this study, we assessed the feasibility of this method by subjecting it to various specimen types: osteological, soft organ, neuroanatomical, regional dissection, and a dedicated 3D‐printed testing phantom. The results demonstrate that the 3D models obtained feature a complete mesh with a high level of detail and a realistic texture. Mesh and texture resolutions were estimated to be approximately 1 and 0.2 mm, respectively. Additionally, stereoscopic animations were both feasible and effective in enhancing depth perception. The simplicity and affordability of this method position it as a technique of choice for creating easily photorealistic anatomical models combined with stereoscopic depth visualization. [ABSTRACT FROM AUTHOR]

Advanced methods of imaging and mapping the healthy and lesioned brain have allowed for the identification of the cortical nodes and white matter tracts supporting the dual neurofunctional organization of language networks in a dorsal phonological and a ventral semantic stream. Much less understood are the anatomical correlates of the interaction between the two streams; one hypothesis being that of a subcortically mediated interaction, through crossed cortico-striato-thalamo-cortical and cortico-thalamo-cortical loops. In this regard, the pulvinar is the thalamic subdivision that has most regularly appeared as implicated in the processing of lexical retrieval. However, descriptions of its connections with temporal (language) areas remain scarce. Here we assess this pulvino-temporal connectivity using a combination of state-of-the-art techniques: white matter stimulation in awake surgery and postoperative diffusion MRI (n = 4), virtual dissection from the Human Connectome Project 3 and 7 T datasets (n = 172) and operative microscope-assisted post-mortem fibre dissection (n = 12). We demonstrate the presence of four fundamental fibre contingents: (i) the anterior component (Arnold's bundle proper) initially described by Arnold in the 19th century and destined to the anterior temporal lobe; (ii) the optic radiations-like component, which leaves the pulvinar accompanying the optical radiations and reaches the posterior basal temporal cortices; (iii) the lateral component, which crosses the temporal stem orthogonally and reaches the middle temporal gyrus; and (iv) the auditory radiations-like component, which leaves the pulvinar accompanying the auditory radiations to the superomedial aspect of the temporal operculum, just posteriorly to Heschl's gyrus. Each of those components might correspond to a different level of information processing involved in the lexical retrieval process of picture naming. [ABSTRACT FROM AUTHOR]

Commonly used to decode the human brain's structural complexity, ex vivo dissection focuses on a given structure or region but cannot depict the whole brain organization (for example, its arterial distribution territories). Where dissection reaches its limit, the combination of tissue sectioning and 3D reconstruction may provide a volume for the assessment of structures from any view angle, following them dynamically to understand their spatial relationships. However, to produce sections, standard histological tissue processing protocols for paraffin embedding cannot be applied to a cerebral hemisphere as the latter is extensively larger than the conventional specimens. This paper presents a protocol for paraffin embedding of the whole human cerebral hemisphere and a method to reconstruct 3D volumes from serially sectioned and photographed paraffin blocks containing embedded hemispheres. Seven ex vivo whole human cerebral hemispheres were included, two were serially sectioned. Main cerebral arteries were injected with colored media to label arterial territories. A detailed description of every step, from tissue processing to image acquisition of cut blockfaces and volume reconstruction, is provided. Tissue processing and section cutting were reproducible, and the former provided complete and homogeneous paraffin wax impregnation. 3D visualization of the reconstructed whole human cerebral hemisphere successfully showed the distribution territories of the main cerebral arteries. In addition, we discuss the challenges we faced and overcame while developing the presented method and highlight its originality. [ABSTRACT FROM AUTHOR]

Advances in the techniques for assessing human cerebral white matter have recently contributed to greater attention to structural connectivity. Yet, little is known about the vascularization of most white matter fasciculi and the fascicular composition of the vascular territories. This paper presents an original method to label the arterial supply of macroscopic white matter fasciculi based on a standardized protocol for post-mortem injection of colored material into main cerebral arteries combined with a novel fiber dissection technique. Twelve whole human cerebral hemispheres obtained post-mortem were included. A detailed description of every step, from obtaining the specimen to image acquisition of its dissection, is provided. Injection and dissection were reproducible and manageable without any sophisticated equipment. They successfully showed the arterial supply of the dissected fasciculi. In addition, we discuss the challenges we faced and overcame during the development of the presented method, highlight its originality. Henceforth, this innovative method serves as a tool to provide a precise anatomical description of the vascularization of the main white matter tracts. [ABSTRACT FROM AUTHOR]

The trigeminal system is considered a prominent actor in brain nociceptive innervation. The trigeminovascular system is mainly composed of pseudounipolar neurons located within the trigeminal ganglion, whose dendrites originate in cerebral blood vessels. Anatomical studies demonstrating anatomical continuity between perivascular fibers and the trigeminal system are lacking. This issue is addressed in this study. Eleven cadaveric heads obtained from a body donation program were fixed in formalin. We performed a microanatomical study of the cavernous carotid‐trigeminal interface and a histological examination of the tissue bridges crossing the virtual space between the medial aspect of the trigeminal ganglion and ophthalmic nerve and the lateral aspect of the cavernous segment of the internal carotid artery. Very strong adhesion was observed between the horizontal segment of the artery and the ophthalmic nerve in all specimens. The virtual space in this interface was crossed by a web of delicate filaments. Histological examination demonstrated the presence of nerve fibers in all samples. In this study, the carotid‐trigeminal interface has been described in greater detail than ever before and could provide insight into disorders related to the trigeminovascular system. As the present results do not allow the exact nature of the axons to be affirmed, further investigation is necessary. [ABSTRACT FROM AUTHOR]

The text discusses the rise of predatory publishing in the scientific community. It highlights the factors that contribute to researchers becoming prey to predatory journals, such as the pressure to publish and the limited resources available to early-career researchers. Predatory journals exploit researchers who are not proficient in English and offer lower publication fees and faster processing times. The text emphasizes the negative consequences of publishing in predatory journals and the need to address the factors that allow them to thrive. [Extracted from the article]

White matter vasculature plays a major role in the pathophysiology of permanent neurological deficits following a stroke or progressive cognitive alteration related to small vessel disease. Thus, knowledge of the complex vascularization and functional aspects of the deep white matter territories is paramount to comprehend clinical manifestations of brain ischaemia. This review provides a structured presentation of the existing knowledge of the vascularization of the human cerebral white matter from seminal historical studies to the current literature. First, we revisit the highlights of prenatal development of the endoparenchymal telencephalic vascular system that are crucial for the understanding of vessel organization in the adult. Second, we reveal the tangled history of debates on the existence, clinical significance and physiological role of leptomeningeal anastomoses. Then, we present how conceptions on white matter vascularization transitioned from the mixed ventriculopetal/ventriculofugal theory, in which a low-flow area was interposed in between concurrent arterial flows, to the purely ventriculopetal theory. The latter model explains variable white matter sensitivity to ischaemia by various organizations of ventriculopetal vessel terminals having different origin/length properties and interconnection patterns. Next, arteries supplying primarily the white matter are described according to their length and overall structure. Furthermore, the known distribution territories, to date, are studied in relation to primary anatomical structures of the human cerebral white matter, emphasizing the sparsity of the 'ground truth' data available in the literature. Finally, the implications for both large vessel occlusion and chronic small vessel disease are discussed, as well as the insights from neuroimaging. All things considered, we identify the need for further research on deep white matter vascularization, especially regarding the arterial supply of white matter fibre tracts. [ABSTRACT FROM AUTHOR]

INTRODUCTION: Although the role of trunk exercises in the chronic phase of stroke is acknowledged, the addition of specific inpatient training in the subacute stage is a matter of debate and varies among centers. Recent new evidence suggests the question should be revisited. OBJECTIVE: To assess the impact of the addition of specific trunk training to inpatient rehabilitation protocols after a recent stroke. METHODS: A systematic review was performed assessing the impact of inpatient trunk training. The search was performed in LILACS, SciELO, PEDro, Cochrane, and NCBI PubMed databases for clinical trials published up to December 31st, 2017. The initial bibliographic research identified 3202 articles. After analyzing the titles, 19 abstracts were selected for detailed analysis. After application of the eligibility criteria, the final selection included nine studies. Outcome measurements from the same evaluation instruments were submitted to a meta-analysis to improve homogeneity (7 studies). RESULTS: All patients in the included studies were recruited less than three months after a stroke. Seven studies assessed trunk control using the Trunk Impairment Scale (TIS). There was a significant improvement in trunk control with a pooled increase in TIS score of 3.3 points from the baseline (CI95:2.54–4.06, p < 0.0001). Three studies assessed balance using the Brunel Balance Assessment (BBA) scale. There was also a significant improvement in balance with a pooled increase in BBA score of 2.7 points (CI95:1.5–4.03, p < 0.0001). The Berg Balance Scale was used for balance assessment in three studies. The meta-analysis of their results showed a pooled increase of 13.2 points (CI95:9.49–16.84, p < 0.0001). Weight transfer was evaluated in four studies using different methods. The addition of inpatient trunk exercises was associated with an improvement in the ability to transfer the trunk laterally in three studies. CONCLUSION: The introduction of trunk-based inpatient training protocols brings short-term benefits in trunk performance and balance in stroke patients. [ABSTRACT FROM AUTHOR]

A rostrocaudal pathway connecting the temporal and parietal lobes was described in monkeys using autoradiography and was named the middle longitudinal fasciculus (MdLF). Recently, the use of diffusion tensor tractography has allowed it to be depicted in human volunteers. In the present study, a technique of fiber dissection was used in 18 cadaveric human brains to investigate the presence of this fasciculus and to detail its anatomical relationships. On the basis of our findings, fiber dissection provides evidence for a long horizontal bundle medial to the arcuate fasciculus and extending to the superior temporal gyrus. Its fibers occupy the lateral-most layer of the upper portion of the stratum sagittale and partially cover the inferior fronto-occipital fasciculus, which is situated deeper and slightly inferiorly. Whereas Md LF fibers continue on a relatively superficial level to reach the superior temporal gyrus, the inferior fronto-occipital fasciculus penetrates the deep temporal white matter and crosses the insular lobe. Although diffusion tensor imaging suggests that the Md LF terminates in the angular gyrus, this was not confirmed by the present study. These long association fibers continue onward posteriorly into upper portions of the occipital lobe. Further studies are needed to understand the role of the Md LF in brain function. [ABSTRACT FROM AUTHOR]

Background and purpose Prompt recanalization of cerebral arteries in patients diagnosed with acute ischemic stroke is known to be associated with a better clinical outcome. The aim of this study was to present our initial experience regarding the efficacy and safety of the Solitaire FR as a revascularization device. Methods 56 consecutive patients presenting with acute ischemic stroke underwent intra-arterial therapy using the Solitaire FR revascularization device. Immediate angiographic results and early clinical outcomes are presented. Results Solitaire FR was successful in achieving recanalization in 50 out of 56 patients (89%) with a final Thrombolysis in Cerebral Infarction score ⩾2b. Five out of 56 patients had procedure related complications: two asymptomatic subarachnoid hemorrhages, two thromboembolic events and one symptomatic intracranial hemorrhage (PH2). Thirty patients (53.5%) demonstrated at discharge a National Institutes of Health Stroke Scale Score of ⩽1 or an improvement of at least 10 points from baseline, and 26 patients (46%) had a modified Rankin Score ⩽2. Conclusions Solitaire FR is successful in achieving a high rate of arterial recanalization with a low complication rate. The Solitaire FR is a promising thrombectomy tool with a high degree of effectiveness, safety and ease of use. [ABSTRACT FROM AUTHOR]

Glioblastoma Multiforme (GBM) invasiveness renders complete surgical resection impossible and highly invasive Glioblastoma Initiating Cells (GICs) are responsible for tumour recurrence. Their dissemination occurs along pre-existing fibrillary brain structures comprising the aligned myelinated fibres of the corpus callosum (CC) and the laminin (LN)-rich basal lamina of blood vessels. The extracellular matrix (ECM) of these environments regulates GIC migration, but the underlying mechanisms remain largely unknown. In order to recapitulate the composition and the topographic properties of the cerebral ECM in the migration of GICs, we have set up a new aligned polyacrylonitrile (PAN)-derived nanofiber (NF) scaffold. This system is suitable for drug screening as well as discrimination of the migration potential of different glioblastoma stem cells. Functionalisation with LN increases the spatial anisotropy of migration and modulates its mode from collective to single cell migration. Mechanistically, equally similar to what has been observed for mesenchymal migration of GBM in vivo, is the upregulation of galectin-3 and integrin-β1 in Gli4 cells migrating on our NF scaffold. Downregulation of Calpain-2 in GICs migrating in vivo along the CC and in vitro on LN-coated NF underlines a difference in the turnover of focal adhesion (FA) molecules between single-cell and collective types of migration. [ABSTRACT FROM AUTHOR]

Aim: To assess a program combining virtual reality (VR) games and proprioceptive neuromuscular facilitation (PNF) and to compare it with the standalone techniques in stroke survivors. Methods: A randomized controlled clinical trial. A total of 48 participants were recruited in the outpatient clinic of a University Hospital in Salvador, Brazil. They were randomly assigned to 3 groups (n = 16 each): PNF, VR, and PNF/VR. Participants attended twice-weekly 50-minute sessions over a 2-month period. The PNF/VR group performed both PNF and VR exercises employing Nintendo Wii electronic games. Motor performance was assessed before and immediately after the treatment using the Fugl-Meyer Assessment scale. Results: An improvement in the mean scores was observed after treatment independent of the allocation group with significant intragroup changes: 14.5, 10.5, and 10.4 for PNF, VR, and PNF/VR, respectively. Score changes were also observed in the analyses of specific sections as follows: (1) a significant improvement in the passive movement and pain score was observed in the PNF and PNF/VR groups; (2) the same was observed for the motor function of the upper limb in all groups, for the motor function of the lower limb in the VR group and for balance in the PNF and PNF/VR groups. Conclusions: The use of a program combining virtual rehabilitation and PNF presented results that were comparable with those obtained with the isolated techniques. [ABSTRACT FROM AUTHOR]

Aim: To assess a program combining virtual reality (VR) games and proprioceptive neuromuscular facilitation (PNF) and to compare it with the standalone techniques in stroke survivors. Methods: A randomized controlled clinical trial. A total of 48 participants were recruited in the outpatient clinic of a University Hospital in Salvador, Brazil. They were randomly assigned to 3 groups (n = 16 each): PNF, VR, and PNF/VR. Participants attended twice-weekly 50-minute sessions over a 2-month period. The PNF/VR group performed both PNF and VR exercises employing Nintendo Wii electronic games. Motor performance was assessed before and immediately after the treatment using the Fugl-Meyer Assessment scale. Results: An improvement in the mean scores was observed after treatment independent of the allocation group with significant intragroup changes: 14.5, 10.5, and 10.4 for PNF, VR, and PNF/VR, respectively. Score changes were also observed in the analyses of specific sections as follows: (1) a significant improvement in the passive movement and pain score was observed in the PNF and PNF/VR groups; (2) the same was observed for the motor function of the upper limb in all groups, for the motor function of the lower limb in the VR group and for balance in the PNF and PNF/VR groups. Conclusions: The use of a program combining virtual rehabilitation and PNF presented results that were comparable with those obtained with the isolated techniques. [ABSTRACT FROM AUTHOR]

No abstract available Copyright © 2010 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]