The presentation of cortical arteries is challenging, as most of their course is hidden in the depth of the sulci. Despite that, demonstrating the arteries on the cortical surface is a standard way of their presentation. To keep advantages of surface presentation while lessening its limitation, we propose a novel context-related method of cerebrovasculature presentation by cortical openings consisting in the removal of a selected region from the cortical mantle and exposing underlying structures. We also introduce a reverse than standard vessel-to-context mapping from a gyrus/lobule to vessels supplying it.The method has the following steps: define a cortical opening, develop a tool to perform them, create cortical openings for gyri and lobules with underlying white matter and intracranial arteries, generate labeled and parcellated images for the created openings, and integrate the cortical opening images with the NOWinBRAIN public repository of 8600 3D neuroimages.The cortical openings are created for 64 gyri and six lobules for the left and right cerebral hemispheres resulting in 210 images arranged in triples as spatially corresponding non-parcellated and unlabeled, parcellated by color and unlabeled, and parcellated and labeled images.The cortical opening approach, generally, increases vessel exposure in a higher number of depicted branches, revealing arteries otherwise hidden deep in sulci, a more complete vessel course, and a lower number of required views.The gyrus/lobule-to-arteries mapping facilitates exploration of a studied region, encapsulates all local arteries, and reduces vascular complexity by decomposing the entire vascular system into smaller sets involved in the studied region.

The delineation of cortical areas on magnetic resonance images (MRI) is important for understanding the complexities of the developing human brain. The previous version of the Melbourne Children\'s Regional Infant Brain (M-CRIB-S) (Adamson et al. Scientific Reports, 10(1), 10, 2020) is a software package that performs whole-brain segmentation, cortical surface extraction and parcellation of the neonatal brain. Available cortical parcellation schemes in the M-CRIB-S are the adult-compatible 34- and 31-region per hemisphere Desikan-Killiany (DK) and Desikan-Killiany-Tourville (DKT), respectively. We present a major update to the software package which achieves two aims: 1) to make the voxel-based segmentation outputs derived from the Freesurfer-compatible M-CRIB scheme, and 2) to improve the accuracy of whole-brain segmentation and cortical surface extraction. Cortical surface extraction has been improved with additional steps to improve penetration of the inner surface into thin gyri. The improved cortical surface extraction is shown to increase the robustness of measures such as surface area, cortical thickness, and cortical volume.

Although the term sulcus is known for almost four centuries, its formal, precise, consistent, constructive, and quantitative definition is practically lacking. As the cerebral sulci (and gyri) are vital in cortical anatomy which, in turn, is central in neuroeducation and neuroimage processing, a new sulcus definition is needed. The contribution of this work is threefold, namely to (1) propose a new, morphology-based definition of the term sulcus (and consequently that of gyrus), (2) formulate a constructive method for sulcus calculation, and (3) provide a novel way for the presentation of sulci. The sulcus is defined here as a volumetric region on the cortical mantle between adjacent gyri separated from them at the levels of their gyral white matter crest lines. Consequently, the sulcal inner surface is demarcated by the crest lines of the gyral white matter of its adjacent gyri. Correspondingly, the gyrus is defined as a volumetric region on the cortical mantle separated from its adjacent sulci at the level of its gyral white matter crest line. This volumetric sulcus definition is conceptually simple, anatomy-based, educationally friendly, quantitative, and constructive. Considering the sulcus as a volumetric object is a major differentiation from other works. Based on the introduced sulcus definition, a method for volumetric sulcus construction is proposed in two, conceptually straightforward, steps, namely, sulcal intersection formation followed by its propagation which steps are to be repeated for every sulcal segment. These sulcal and gyral constructions can be automated by applying existing methods and public tools. As a volumetric sulcus forms an imprint into the white matter, this enables prominent sulcus presentation. Since this type of presentation is novel yet unfamiliar to the reader, also a dual surface presentation was proposed here by employing the spatially co-registered white matter and cortical surfaces. The results were presented as dual surface labeled sulci on eight standard orthogonal views, anterior, left lateral, posterior, right lateral, superior, inferior, medial left, and medial right by using a 3D brain atlas. Moreover, additional 108 labeled images were created with sulcus-oriented views for 27 individual left and right sulci forming 54 dual white matter-cortical surface images strengthening in this way the educational value of the proposed approach. These images were included for public use in the NOWinBRAIN neuroimage repository with over 7700 3D images available at www.nowinbrain.org. The results demonstrated the superiority of white matter surface sulci presentation over the standard cortical surface and cross-sectional presentations in terms of sulcal course, continuity, size, shape, width, depth, side branches, and pattern. To my best knowledge, this is the first work ever presenting the labeling of sulci on all cerebral white matter surfaces as well as on dual white matter-cortical surfaces. Additionally to neuroeducation, three other applications of the proposed approach were discussed, sulcal reference maps, sulcus quantification in terms of new parameters introduced here (sulcal volume, wall skewness, and the number of white matter basins), and an atlas-assisted tool for exploration and studying of cerebral sulci and gyri .

Surgical resection of brain tumours aims at the maximal safe resection of the pathological tissue with minimal functional impairment. To achieve this objective, reliable anatomical landmarks are indispensable to navigate into the brain. The neuronavigation system can provide information to target the location of the patient\'s lesion, but after the craniotomy, a brain shift and relaxation mismatch with it often occur. By contrast, sulci/gyri are topological cerebral landmarks in individual patients and do shift with the brain parenchyma during lesion removal, but remain independent from brain shift in relation to the sulci/gyri. Here, we present a case report of a novel strategy based on anatomical landmarks to guide intraoperative brain tumour resection, without using a standard neuronavigation system. A preoperative brain mapping of the peri-tumoural sulci by the MRI and surface reconstruction was followed by confirmation of the anatomical landmarks for the motor cortex using navigated transcranial magnetic stimulation. The resulting location was used as a seed for diffusion tensor imaging tractography to reconstruct the corticospinal tracts. These selected cortical landmarks (sulci/gyri) delimited the margins of the two lesions and the specific location under which the corticospinal tract courses, thus facilitating monitoring of the peri-tumoural region during brain resection. In this case, 96% of the brain tumour from the pericentral somatomotor region was successfully removed without chronic post-operative motor impairments. This approach is based on cortical anatomy that is fixed during surgery and does not suffer from the brain shift that could misplace the lesion according to the neuronavigation system.

Cortical thickness varies throughout the cortex in a systematic way. However, it is challenging to investigate the patterns of cortical thickness due to the intricate geometry of the cortex. The cortex has a folded nature both in radial and tangential directions which forms not only gyri and sulci but also tangential folds and intersections. In this article, cortical curvature and depth are used to characterize the spatial distribution of the cortical thickness with much higher resolution than conventional regional atlases. To do this, a computational pipeline was developed that is capable of calculating a variety of quantitative measures such as surface area, cortical thickness, curvature (mean curvature, Gaussian curvature, shape index, intrinsic curvature index, and folding index), and sulcal depth. By analyzing 501 neurotypical adult human subjects from the ABIDE-I dataset, we show that cortex has a very organized structure and cortical thickness is strongly correlated with local shape. Our results indicate that cortical thickness consistently increases along the gyral-sulcal spectrum from concave to convex shape, encompassing the saddle shape along the way. Additionally, tangential folds influence cortical thickness in a similar way as gyral and sulcal folds; outer folds are consistently thicker than inner.

BACKGROUND: Different surgical approaches have been described for selective amygdalohippocampectomy in patients with pharmacoresistant temporal lobe epilepsy. The aim of this study was to report the results of the innovative anterior trans-superior temporal gyrus approach in a single-center series.
METHODS: Patients\' characteristics, postoperative outcomes, and complications were reviewed in a series of 8 consecutive patients with temporal lobe epilepsy operated on using the anterior trans-superior temporal gyrus approach between November 2015 and April 2017.
RESULTS: Over a mean 2.5-year follow-up, 7 of 8 patients (87.5%) remained seizure-free (Engel class I). Only 1 patient (12.5%) was not cured (Engel class III) with no clear explanation for treatment failure. Mean operative time was 237 minutes, which was 80 minutes shorter compared with the classic transsylvian approach. No perioperative deaths were recorded and there were no visual field defects or visual acuity impairments secondary to the approach. One patient experienced a left posterior thalamocapsular stroke.
CONCLUSIONS: The anterior trans-superior temporal gyrus approach is feasible, fast, and safe for selective amygdalohippocampectomy in patients with drug-refractory temporal lobe epilepsy. This approach allows preservation of the optic radiation but cuts part of the uncinate fasciculus and potentially the anterior aspect of the anterior bundle of the middle longitudinal fasciculus.

Octopods are masters of camouflage and solve complex tasks, and their cognitive ability is said to approach that of some small mammals. Despite intense interest and some research progress, much of our knowledge of octopus neuroanatomy and its links to behavior and ecology comes from one coastal species, the European common octopus, Octopus vulgaris. Octopod species are found in habitats including complex coral reefs and the relatively featureless mid-water. There they encounter different selection pressures, may be nocturnal or diurnal, and are mostly solitary or partially social. How these different ecologies and behavioral differences influence the octopus central nervous system (CNS) remains largely unknown. Here we present a phylogenetically informed comparison between diurnal and nocturnal coastal and a deep-sea species using brain imaging techniques. This study shows that characteristic neuroanatomical changes are linked to their habits and habitats. Enlargement and division of the optic lobe as well as structural foldings and complexity in the underlying CNS are linked to behavioral adaptation (diurnal versus nocturnal; social versus solitary) and ecological niche (reef versus deep sea), but phylogeny may play a part also. The difference between solitary and social life is mirrored within the brain including the formation of multiple compartments (gyri) in the vertical lobe, which is likened to the vertebrate cortex. These findings continue the case for convergence between cephalopod and vertebrate brain structure and function. Notably, within the current push toward comparisons of cognitive abilities, often with unashamed anthropomorphism at their root, these findings provide a firm grounding from which to work.

Folds of the cerebral cortex, which are called gyri and sulci, are one of the most prominent features of the mammalian brain. However, the mechanisms underlying the development and malformation of cortical folds are largely unknown, mainly because they are difficult to investigate in mice, whose brain do not have cortical folds. To investigate the mechanisms underlying the development and malformation of cortical folds, we developed a genetic manipulation technique for the cerebral cortex of gyrencephalic carnivore ferrets. Genes-of-interest can be expressed in the ferret cortex rapidly and efficiently. We also demonstrated that genes-of-interest can be knocked out in the ferret cortex by combining in utero electroporation and the CRISPR/Cas9 system. Using our technique, we found that fibroblast growth factor (FGF) signaling and sonic hedgehog (Shh) signaling are crucial for cortical folding. In addition, we found that FGF signaling and Shh signaling preferentially increased outer radial glial cells and the thickness of upper layers of the cerebral cortex. Furthermore, over-activation of FGF signaling and Shh signaling resulted in polymicrogyria. Our findings provide in vivo data about the mechanisms of cortical folding in gyrencephalic mammals. Our technique for the ferret cerebral cortex should be useful for investigating the mechanisms underlying the development and diseases of the cerebral cortex that cannot be investigated using mice.

Our knowledge of the vascularization of the precentral gyrus by branches of the anterior cerebral artery (ACA) relies mainly on anatomical cadaveric dissection. A distal branch of the ACA known as the posterior internal frontal artery (PIFA) is thought to vascularize the precentral gyrus responsible for proximal arm movement; however, no clinical correlation has yet been reported to confirm this relation. In this manuscript, we report a case of coil migration in the PIFA, causing proximal arm weakness in a 58-year-old woman treated for aneurysmal subarachnoid hemorrhage. The occurrence of clinical signs immediately following coil migration into the PIFA, combined with evidence of stroke in the cortical territory related to arm movement as seen on imaging, indicates that the PIFA indeed can vascularize this lateral portion of the precentral gyrus. This case confirms our current understanding of the vascularization of the precentral gyrus by distal ACA branches, in particular the PIFA.

UNASSIGNED: During the surgery for intrinsic brain lesions, it is important to plan the proper site of the craniotomy and to identify the relations with the gyri and superficial veins. This might be a challenge, especially in small subcortical lesions and when there is a distortion of the cortical anatomy.
UNASSIGNED: Using the free computer software Osirix, we have created a 3-dimensional reconstruction of the head and cerebral showing the gyri and superficial veins. With the aid of some tools, it is possible to create a colored image of the lesion and also to calculate the distance between the areas of interest and some easily identifiable structure, making it easier to plan the site of the craniotomy identify the topography of the lesion.
UNASSIGNED: The reconstructions were compared to the intraoperative view. We found this technique to be useful to help identify the gyri and cortical veins and use them to find the lesions. The use of a region of interest to show better the lesion under the cortical surface and in the three-dimensional reconstruction of the head was also helpful.
UNASSIGNED: This is a low-cost and easy technique that can be quickly learned and performed before every surgery. It helps the surgeon to plan a safe craniotomy and lesionectomy.