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Introduction: The corpus callosum, a principal commissural fibre-bundle of the brain, connects the two cerebral hemispheres, facilitating interhemispheric communication, cognitive and emotional processes. The anatomical definition of the isthmus of the corpus callosum remains unclear in literature with limited studies focusing on this region. This research addresses this gap by providing a detailed anatomical description of the isthmus of the corpus callosum in a South African cadaveric sample. Methods: Digital photographs of thirty embalmed cadaver brains were analysed and measurements of the corpus callosum and isthmus were taken, as seen on a midsagittal section. Results: The results revealed no significant differences in isthmus measurements when comparing the sex of the cadavers. The average length of the isthmus accounted for approximately 16.66 % of the total length of the corpus callosum. The isthmus constituted approximately 17.92 % of the corpus callosum surface area. Females tend to have a larger isthmus relative to the size of their corpus callosum. The prevalence of a posterior notch on the superior border of the corpus callosum was found to be approximately 46.66 % in the studied sample, with males showing a slightly higher prevalence. Conclusion: Since the isthmus constituted almost 20 % of the total surface area of the corpus callosum, as seen on midsagittal sections, it should be acknowledged as a fifth part. It should further be included in the undergraduate neuroanatomy curriculum and textbooks, which is currently lacking this information. This research recommends expanding the sample size, encompassing diverse demographics, employing fresh cadavers, and utilize three-dimensional imaging to understand the isthmus of the corpus callosum and its relevance to neuropsychiatric conditions and brain morphology.

Background: The size and shape of the adult corpus callosum (CC) may vary with gender. There is, however, less literature available on data involving the morphometry of CC among the Indian population. Aims and Objectives: To measure the size of CC using magnetic resonance imaging (MRI) scans of normal Indian adult females and males and identify gender-related differences, if any. Materials and Methods: The dimensions of CC were measured on MRI scans on a midsagittal section view belonging to 150 (59 females, 91 males) normal Indian adults (North India) using e-measurement tools. The measurements included the maximum length and height of CC, the thickness of various parts of CC, the CC index (CCI), and the distance of CC from the frontal and occipital poles of the cerebral hemisphere. The study was carried out in the Department of Anatomy in collaboration with the Department of Radiodiagnosis, King George’s Medical University, U.P., Lucknow, India. The data was analyzed using the statistical package for social sciences, 23rd version. Means were compared for significant differences using the independent unpaired t-test. Results: The mean length of the CC was found to be 6.94±0.63 cm; mean height was 2.57±0.43 cm; the mean thickness of the genu was 9.16±2.26 mm; the mean thickness of the body was 5.09±0.99 mm; the mean thickness of splenium was 9.10±2.22 mm; the mean distance from the frontal pole was 3.66±0.35 cm; the mean distance from the occipital pole was 5.70±0.74 cm; and the mean CCI calculations showed to be 3.37±0.56. All measurements were found to be greater in males as compared to females except mean height (males 2.56±0.47 cm; females 2.59±0.37 cm) and mean thickness of the body (males 5.04±0.94 mm; females 5.17±1.06 mm). A statistically significant difference was observed in the distance of CC from the frontal pole in our population with respect to gender (P=0.03). Conclusion: Based on observations made in the study, normative data of CC measurements was generated, and it was found that there was no significant gender-related difference in the morphology of CC; the only significant difference was in the distance of the genu from the frontal pole, which was greater in females as compared to males.

Abstract Background Stroke is a burdensome cerebral eventthat affects many aspects of daily activities such as motion, speech, memory, vision, and cognition. Intravascular laser irradiation of blood (ILIB) is a novel therapy, going beyond conventional rehabilitation modalities, that is effective in stroke recovery. Homocysteine ​​is an important risk factor associated with stroke. However, there are few studies that examine the relationship between ILIB treatment and the level of homocysteine. In recent years, researchers use the single-photon emission computed tomography (SPECT) scan of the brain to evaluate stroke patients and patients with a neurologicdeficit. The present report investigates the clinical effect of ILIB treatment on the level of serum homocysteine, the perfusion change of impaired brain region via SPECT, and the patient’s neurologic appearance. Casepresentation We focus on a case of a 62-year-old man with subacute stroke accompanied with left hemiparesis and hyperhomocysteinemia, who showed dramatic improvement in muscle power, a decreasing level of homocysteine, and increased blood flow of the right cerebral after three-courseILIB treatment. Conclusion We found that ILIB is effective in lowering serum levels of homocysteine and facilitating cerebral circulation for the patient with subacute stroke.

Introduction: Cerebral hemispheres are the two main parts of human brain. Though, the cerebral hemispheres may appear to be identical, one hemisphere is functionally dominant over the other. They also exhibit physical variations. The dominance may be due to lateralisation of cortical functions. In about 90% of the total population, the left hemisphere is dominant over the right where the speech and language areas are located. These areas are situated within the Pars Opercularis (PO) and Pars Triangularis (PT) in the dominant hemisphere of the Lateral Sulcus (Sylvian Fissure). The interhemispheric asymmetry of the Sylvian Fissure (SF) may be the basis of cerebral dominance for language, which is less studied in human beings. These asymmetries are relative and vary according to the functions concerned. Therefore, knowledge of the interhemispheric asymmetries is helpful in neurological diagnosis and management. Aim: To measure the length of the lateral sulcus and its rami on both hemispheres and to study their interhemispheric asymmetry. Materials and Methods: A cross-sectional pilot study was done on 30 whole brains of embalmed adult human cadavers irrespective of sexes taken from the Institute of Anatomy of Madras Medical College, Tamil Nadu, India, between the months of June to August, 2017. The lateral sulcus was measured on the superolateral surface of the brain. All measurements were taken with the help of a thin copper wire placed on the surface, its ends being held in position with artery forceps. The wire was then placed on a graduated metal scale and the lengths of the anterior ascending, anterior horizontal, posterior rami and total length of the lateral sulcus were noted. A data sheet was made using Microsoft excel software and the mean length of each ramus was calculated. Results: The mean total length of the SF was noted to be 8.4±0.51 cm on the right side and 8.8±0.56 cm on the left. The mean length of stem of lateral sulcus was 2.5±0.4 cm and 2.6±0.3 cm on the right and left side, respectively. The mean length of the anterior ascending ramus was found to be 2.7±0.3 cm on the right side and 3.13±0.3 cm on the left side. The mean length of the anterior horizontal ramus was found to be 2.34±0.37 cm on the right side and 2.55±0.4 cm on the left side. The mean length of the posterior ramus was found to be 5.6±0.65 cm on the right side and 6.1±0.63 cm on the left side. Conclusion: The SF and their rami of the left side were longer than of the right side in most specimens. This signifies the functional asymmetry between right and left cerebral hemispheres which may be related to language lateralisation of human brain. This interhemispheric difference has been implicated in various genetic syndromes and behavioural disorders in children particularly involving language milestone.

Recurrent mutations in H3F3A that encodes the histone 3 variant H3.3, lead to amino acid substitutions including K27M and G34R/V-which are observed in high-grade gliomas (HGGs) of children and young adults. Previous studies have focused on gliomas with K27M mutation, whereas gliomas with G34R/V mutation have received little attention. Herein, we report three rare cases of glioblastoma (GBM) with H3.3 G34 mutation arising from a cerebral hemisphere in two children and one young adult. All three cases showed microscopic characteristics of central nervous system primitive neuroectodermal tumor (CNS-PNET, called CNS embryonal tumors in WHO 2016 Revised 4th Edition) and presented H3.3 G34 mutation. H3.3 G34-mutant brain tumors were formerly a group of histopathologically distinct neoplasms, involved in GBM, CNS-PNET, and astroblastoma. However, recent studies have demonstrated that different CNS tumors with H3.3 G34 mutation display coherent epigenetic signatures, implying a single biological origin. Correspondingly, our three cases showed high consistency in tumor location, histological morphology, and molecular phenotype. Their immunophenotypes are similar to astrocytoma, with ATRX loss and TP53 mutation. Therefore it suggests that these H3.3 G34-mutant brain tumors may be a rare entity of HGG.

The effect of orthographic neighbourhood size (N) on lexical decision reaction time differs when words are presented in the left or right visual fields. Evidence suggests a facilitatory N effect (i.e., faster reaction times for words with larger neighbourhoods) in the left visual field. However, the N effect in the right visual field remains controversial: it may have a weaker facilitative role or it may even be inhibitory. In a pre-registered online experiment, we replicated the interaction between N and visual field and provided support for an inhibitory N effect in the right visual field. We subsequently conducted a pre-registered systematic review and meta-analysis to synthesise the available evidence and determine the direction of N effects across visual fields. Based on the evidence, it would seem the effect is inhibitory in the right visual field. Furthermore, the size of the N effect is considerably smaller in the right visual field. Both studies revealed considerable heterogeneity between participants and studies, and we consider the implications of this for future work.

Working memory capacity, the amount of information that may be maintained in mind over a period of seconds, is extremely limited, to a handful of items. Some evidence exists that the number of visual items that may be maintained in working memory is independent for the two hemifields. To test this idea, we trained monkeys to perform visual working memory tasks that required maintenance in memory of the locations and/or shapes of 3–5 visual stimuli. We then tested whether systematic performance differences were present for stimuli concentrated in the same hemifield, vs. distributed across hemifields. We found little evidence to support the expectation that working memory capacity is independent in the two hemifields. Instead, when an advantage of stimulus arrangement was present, it involved multiple stimuli presented in the same hemifield. This conclusion was consistent across variations of the task, performance levels, and apparent strategies adopted by individual subjects. This result suggests that factors such as grouping that favor processing of stimuli in relative proximity may counteract the benefits of independent processing in the two hemispheres. Our results reveal an important property of working memory and place constraints on models of working memory capacity.

Se realizó un estudio descriptivo y prospectivo de 116 pacientes con hemorragia cerebral intraparenquimatosa, comprobada a través de la tomografía axial computarizada, con vistas a precisar los factores pronósticos predeterminados y su influencia sobre la mortalidad en la casuística. Entre los principales resultados sobresalió el predominio de los grupos de 41-50 y 51-60 años (57,7 % entre ambos), la hipertensión arterial como antecedente patológico personal (79,3 %), así como la ocurrencia de hemorragias en los hemisferios cerebrales (45,6 %). En la serie, 49,1 % de sus integrantes presentaban hematomas con volumen de hasta 30 mL y 7,7 % con el doble de ese contenido. Se observó una relación directa entre el volumen de sangre en el parénquima cerebral por encima de 60 mL y el pronóstico final de los afectados.A descriptive and prospective study of 116 patients with cerebral intraparenchymal hemorrhage, shown through the computerized axial tomography (CAT) was carried out, aimed at specifying the predetermined prognosis factors and their influence on the mortality in the case material. Among the main results there were: the prevalence of the 41-50 and 51-60 year groups (57,7 % between both), hypertension as personal pathological history (79,3%), as well as the occurrence of hemorrhages in the cerebral hemispheres (45,6 %). In the series, 49,1 % of the patients presented haematomas with volume of up to 30 mL and 7,7 % with the double of that content. A direct relation was observed between the blood volume in the cerebral parenchyma above 60 mL and the final prognosis of those affected.

Introduction: Various studies have been done regarding variations of circle of Willis, but few literatures are available about the detail configurations on Indian population. Posterior communicating artery is the main collateral channel between the vertebrobasilar and carotid system. It may act as a main source of blood flow via posterior cerebral artery if fetal configuration is present. Aim of the study is to see the bilateral configurations to compare the blood supply of both cerebral hemispheres via posterior cerebral artery in human cadavers. Materials and Methods: Fifty six formalin fixed brains were used for study. The specimens were classified into 3 types and 21 subtypes according to the configuration of the vessel of both hemispheres. As hemodynamic balance is dependent on the calibre of the vessel, the diameter of the arteries were also taken into consideration. Pearson’s correlation had been done. Result: In present study type I is 57.2%, type II is 37.5% and type III is 5.4%. Incidence of unilateral fetal type posterior cerebral artery is in high percentage (33.9%). Greatest diameter of posterior communicating artery is 3.8mm on right and 3.6mm on left side. Significant correlations also have been found between arterial segments of different types. Conclusion: It is expected that the study will help to enrich the knowledge about the arterial predominance of origin of posterior cerebral artery of both cerebral hemispheres in normal or variant cases and its effect on perfusion images.

Dyke-Davidoff-Masson Syndrome (DDMS) is characterized by seizures, facial asymmetry, contralateral hemiplegia and mental retardation. The characteristic radiologic features are cerebral hemiatrophy with homolateral hypertrophy of the skull and sinuses. Here we report a case of a 16 years young girl who presented with seizures severe mental retardation and weakness of left upper-limb and on CT brain was diagnosed to have DDMS. DOI: http://dx.doi.org/10.3126/jonmc.v1i2.7306 Journal of Nobel Medical College (2012), Vol.1 No.2 p.84-86

Patients with focal cerebellar lesions due to tumor or hematoma were evaluated by a neuropsychological test battery, neurological examination and MRI, and cognitive function was correlated with location of the lesions in a study of 21 adult patients at the Department of Neurosurgery, Christian Albrechts Universitat, Kiel, Germany.