Parieto-occipital Research Articles

Fetal brain biometry and cortical development after maternal SARS-CoV-2 infection in pregnancy: A prospective case-control study.

To assess cerebral growth and the development of fetal cortex using neurosonography in fetuses from pregnancies experiencing severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) according to infection timing. Pregnancies with by SARS-CoV-2 during first and second trimesters were prospectively studied and matched with unaffected controls. Enclosed women underwent neurosonography at 30-34 weeks of gestation and corpus callosum (CC) and cerebellar vermis (CV) lengths measured. Further Sylvian fissure (SF), insula. Parieto-occipital fissure (POF), and calcarine sulci fissures (CSF) depths were obtained. The ultrasonographic variables considered were normalized with fetal head size. One hundred and seventy four consecutive pregnancies experiencing SARS COV 2 infection (81 before 14 weeks and 93 later) and 131 not affected pregnancies were considered. General and pregnancy characteristics were similar between the three groups of women. No significant differences existed in CC and CV lengths across groups. Similarly, insula, SF, POF And CSF depth did not result changed in fetuses of affected mothers. SARS-CoV-2 infection does nor resulted associate with differential fetal cortical development or brain growth in mildly symptomatic pregnant women. This information may be useful to reassure infected mothers on the health of their fetuses.

Virtual reality-based sensorimotor adaptation shapes subsequent spontaneous and naturalistic stimulus-driven brain activity.

Our everyday life summons numerous novel sensorimotor experiences, to which our brain needs to adapt in order to function properly. However, tracking plasticity of naturalistic behavior and associated brain modulations is challenging. Here, we tackled this question implementing a prism adaptation-like training in virtual reality (VRPA) in combination with functional neuroimaging. Three groups of healthy participants (N= 45) underwent VRPA (with a shift either to the left/right side, or with no shift), and performed functional magnetic resonance imaging (fMRI) sessions before and after training. To capture modulations in free-flowing, task-free brain activity, the fMRI sessions included resting-state and free-viewing of naturalistic videos. We found significant decreases in spontaneous functional connectivity between attentional and default mode (DMN)/fronto-parietal networks, only for the adaptation groups, more pronouncedly in the hemisphere contralateral to the induced shift. In addition, VRPA was found to bias visual responses to naturalistic videos: Following rightward adaptation, we found upregulation of visual response in an area in the parieto-occipital sulcus (POS) only in the right hemisphere. Notably, the extent of POS upregulation correlated with the size of the VRPA-induced after-effect measured in behavioral tests. This study demonstrates that a brief VRPA exposure can change large-scale cortical connectivity and correspondingly bias visual responses to naturalistic sensory inputs.

Fetal brain biometry and cortical development in congenital heart disease: A prospective cross sectional study.

To evaluate brain biometry and cortical development by neurosonography in fetuses with congenital heart defect (CHD) and evaluate differences among different type of CHD. In a prospective cross sectional study singleton fetus with CHD were matched with controls and grouped into two categories according to the predicted severity of cerebral arterial oxygen deficit induced by the CHD: Group A mildly reduced or normal and Group B moderately to severely reduced. Neurosonography was done at 30-33 weeks to obtain measurements of corpus callosum (CC), cerebellar vermis (CV), Sylvian fissure (SF) insula, parieto-occipital fissure (POF), and calcarine sulci fissures (CSF). All the neurosonographic parameters were adjusted by head circumference (HC). A total of 78 fetuses with CHD (group A 30; group B 48) and 80 matched controls form uncomplicated pregnancies were considered. CHD fetuses have significantly smaller CC, CV, SF, and POF and bigger insula when compared to control fetuses. These differences are more marked in group B fetuses. These differences remained significant after correction for HC values. Fetuses with CHD have an impaired cortical development and these variations are more evident in those with a predicted lower oxygen delivery to the brain.

Role of the parietooccipital fissure and its implications in the pathophysiology of posterior medial temporal gliomas.

The parietooccipital fissure is an anatomical landmark that divides the temporal, occipital, and parietal lobes. More than 40% of gliomas are located in these three lobes, and the temporal lobe is the most common location. The parietooccipital fissure is located just posterior to the medial temporal lobe, but little is known about the clinical significance of this fissure in gliomas. The authors investigated the anatomical correlations between the parietooccipital fissure and posterior medial temporal gliomas to reveal the radiological features and unique invasion patterns of these gliomas. The authors retrospectively reviewed records of all posterior medial temporal glioma patients treated at their institutions and examined the parietooccipital fissure. To clarify how the surrounding structures were invaded in each case, the authors categorized tumor invasion as being toward the parietal lobe, occipital lobe, isthmus of the cingulate gyrus, insula/basal ganglia, or splenium of the corpus callosum. DSI Studio was used to visualize the fiber tractography running through the posterior medial temporal lobe. Twenty-four patients with posterior medial temporal gliomas were identified. All patients presented with a parietooccipital fissure as an uninterrupted straight sulcus and as the posterior border of the tumor. Invasion direction was toward the parietal lobe in 13 patients, the occipital lobe in 4 patients, the isthmus of the cingulate gyrus in 19 patients, the insula/basal ganglia in 3 patients, and the splenium of the corpus callosum in 8 patients. Although the isthmus of the cingulate gyrus and the occipital lobe are located just posterior to the posterior medial temporal lobe, there was a significantly greater preponderance of invasion toward the isthmus of the cingulate gyrus than toward the occipital lobe (p = 0.00030, McNemar test). Based on Schramm's classification for the medial temporal tumors, 4 patients had type A and 20 patients had type D tumors. The parietooccipital fissure determined the posterior border of the tumors, resulting in a unique and identical radiological feature. Diffusion spectrum imaging (DSI) tractography indicated that the fibers running through the posterior medial temporal lobe toward the occipital lobe had to detour laterally around the bottom of the parietooccipital fissure. Posterior medial temporal gliomas present identical invasion patterns, resulting in unique radiological features that are strongly affected by the parietooccipital fissure. The parietooccipital fissure is a key anatomical landmark for understanding the complex infiltrating architecture of posterior medial temporal gliomas.

Visual rating of cortical atrophy in migraine and tension-type headache

Background: Studies of cortical atrophy in migraine and tension-type headache (TTH) have reported inconsistent results. Some studies have reported decreased cortical thickness or volume, while others have reported thickening in the somatosensory and visual cortices in migraine patients. The same controversy is true with respect to episodic and chronic headaches. This study evaluated and compared cortical atrophy in migraine and TTH as well as in episodic and chronic headache. Methods: The study included 43 (37 female) migraine and 15 (12 female) TTH patients. Demographic, clinical, and brain magnetic resonance imaging (MRI) data were evaluated. 1.5 Tesla MRI brain coronal T2 sequences were reviewed by two neurologists, and atrophy was graded according to a visual rating scale (VRS). Two neurologists jointly evaluated and scored cortical thickness on a Likert scale of 0 to 3 or 4 at the following sites bilaterally: olfactory sulcus, anterior cingulate sulcus, circular insular sulcus, anterior temporal and medial temporal lobes, and posterior cingulate and parieto-occipital sulci. The scores at all sites were then summed into a total atrophy score (TAS) for each subject. Results: There was no significant difference between the migraine and TTH groups regarding demographics, clinical findings, and atrophy scores in any particular region or with respect to the TAS. When we divided our study subjects into episodic and chronic headache groups, there was no significant difference between these groups in terms of demographic and clinical findings or individual and total atrophy scores. Conclusions: These results are in line with previous studies that have reported no differences between migraine and TTH in terms of cortical atrophy.

Cardiac-Brain Dynamics Depend on Context Familiarity and Their Interaction Predicts Experience of Emotional Arousal.

Our brain continuously interacts with the body as we engage with the world. Although we are mostly unaware of internal bodily processes, such as our heartbeats, they may be influenced by and in turn influence our perception and emotional feelings. Although there is a recent focus on understanding cardiac interoceptive activity and interaction with brain activity during emotion processing, the investigation of cardiac–brain interactions with more ecologically valid naturalistic emotional stimuli is still very limited. We also do not understand how an essential aspect of emotions, such as context familiarity, influences affective feelings and is linked to statistical interaction between cardiac and brain activity. Hence, to answer these questions, we designed an exploratory study by recording ECG and EEG signals for the emotional events while participants were watching emotional movie clips. Participants also rated their familiarity with the stimulus on the familiarity scale. Linear mixed effect modelling was performed in which the ECG power and familiarity were considered as predictors of EEG power. We focused on three brain regions, including prefrontal (PF), frontocentral (FC) and parietooccipital (PO). The analyses showed that the interaction between the power of cardiac activity in the mid-frequency range and the power in specific EEG bands is dependent on familiarity, such that the interaction is stronger with high familiarity. In addition, the results indicate that arousal is predicted by cardiac–brain interaction, which also depends on familiarity. The results support emotional theories that emphasize context dependency and interoception. Multimodal studies with more realistic stimuli would further enable us to understand and predict different aspects of emotional experience.

Skin landmarks to main cerebral structures: how to identify the main cerebral sulci? A radiological study about lateral, central, and parietooccipital sulci.

In a previous cadaveric work, we identified and described useful and reproducible surface skin landmarks to lateral sulcus, central sulcus and preoccipital notch. Potential limitations of this cadaveric study have been raised. Thus, the objective of this study was to confirm radiologically the accuracy of these previously described surface skin landmarks on brain magnetic resonance imaging (MRI) of healthy subjects. Healthy adult volunteers underwent a high-resolution brain MRI and measurements of the orthogonal skin projection (OSP) of the anterior sylvian point (AsyP), the superior Rolandic point (SroP) and the parietooccipital sulcus were made from nasion, zygomatic bone and inion, respectively. These measures were compared to our previous cadaveric findings. Thirty-one healthy volunteers were included. ASyP was 33 ± 2mm above the zygomatic arch, and 32.3 ± 3mm behind the orbital rim. The lateral sulcus was 63.5 ± 4mm above the tragus. The SRoP was 196.9 ± 6mm behind the nasion. The superior point of the parietooccipital sulcus was 76.0 ± 4mm above the inion. These measurements are comparable to our previously described cadaveric findings. We here described three useful, simple and reproducible surface skin landmarks to lateral, central and parietooccipital sulci. Knowledge of these major landmarks is mandatory for Neurosurgical practice, especially in an emergency setting.

Assessing the specificity of the relationship between brain alpha oscillations and tonic pain

Recent research proposed that the slowing of individual alpha frequency (IAF) could be an objective marker of pain. However, it is unclear whether this research can fully address the requirements of specificity and sensitivity of IAF to the pain experience. Here, we sought to develop a robust methodology for assessing the specificity of the relationship between alpha oscillations and acute tonic pain in healthy individuals. We recorded electroencephalography (EEG) of 36 volunteers during consecutive 5-minute sessions of painful hot water immersion, innocuous warm water immersion and aversive, non-painful auditory stimulus, matched by unpleasantness to the painful condition. Participants rated stimulus unpleasantness throughout each condition. We isolated two regions of the scalp displaying peak alpha activity across participants: centro-parietal (CP) and parieto-occipital (PO) ROI. In line with previous research our findings revealed decreased IAF during hot compared with warm stimulation, however the effect was not specific for pain as we found no difference between hot and sound in the CP ROI (compared to baseline). In contrast, the PO ROI reported the same pattern of differences, but their direction was opposite to the CP in that this ROI revealed faster frequency during hot condition than controls. Finally, we show that IAF in both ROIs did not mediate the relationship between the experimental manipulation and the affective experience. Altogether, these findings emphasize the importance of a robust methodological and analytical design to disclose the functional role of alpha oscillations during affective processing. Likewise, they suggest the absence of a causal role of IAF in the generation of acute pain experience in healthy individuals.

Diagnostic Value of Sylvian Fissure Hyperechogenicity in Fetal SAH.

Fetal SAH is an intracranial malformation. The typical diagnostic features of fetal SAH in ultrasound have not been reported. This study aimed to evaluate the diagnostic value of Sylvian fissure hyperechogenicity by prenatal ultrasound in fetuses with SAH. The features on ultrasound and MR imaging of 10 fetuses with SAH were reviewed and summarized. The diagnostic value of the Sylvian fissure in fetal SAH by prenatal ultrasound was evaluated. The typical and most obvious manifestations of SAH during the prenatal period were hyperechogenicity in the subarachnoid cavity, especially in the Sylvian fissure; all 10 cases (10/10) had such manifestations. Other manifestations included a hyperecho in other sulci (6/10), especially in the subfrontal sulcus, superior temporal sulcus, or parieto-occipital sulcus; a hyperecho in the cisterns (8/10), especially in the suprasellar cistern, posterior cranial fossa, cisterna ambiens, or quadrigeminal cistern; and a hyperecho around the anterior and posterior longitudinal fissures (2/10). Combined hemorrhage in the parenchymal layer or ventricles (9/10) was found. In addition, Doppler ultrasound showed that the peak flow velocity in the MCA increased in 6 cases (6/10). The homogeneous hyperechogenicity of the Sylvian fissure is an important clue for detecting and diagnosing fetal SAH by prenatal ultrasound. A diagnostic approach has been proposed for fetal SAH, which has great significance in further prognosis.

Role of Ultrasonography in the Evaluation of Normal Developmental Pattern of Fetal Cerebral Sulci Between 18 and 32 Weeks of Gestational Age.

BackgroundBrain development is a crucial process of intrauterine life and can be readily visualized on ultrasonography. This study aims to visualize developmental patterns of various fetal cerebral sulci using ultrasonography between 18 and 32 weeks of gestation. Sulci are best visualized on images that are taken perpendicular to their expected course of development. Initially, they appear as small dot/dimple on the brain surface and later develop into a V-shaped indentation and finally deepen to form notch and echogenic line into the brain forming a Y-shaped configuration.Material and methodsThis was a cross-sectional observational study conducted on 241 antenatal mothers with a singleton pregnancy between 18 and 32 weeks of gestational age. Demographic and clinical data were obtained. Ultrasonography was performed using PHILIPS EPIQ 5, a curvilinear probe of frequency 2-5MHz. Sulci/fissures that are reported to appear early on anatomical studies were evaluated, specifically the parieto-occipital fissure, calcarine fissure, cingulate sulci, insula/Sylvian fissure, and convexity sulci. Comparison of the categorical outcomes was performed between study groups using the chi-square test. A p-value of <0.05 was considered statistically significant.ResultsThe study included 241 participants. The mean age of antenatal mothers was 24.09 ± 4.13 years, and the mean fetal gestational age was 24.99 ± 4.13 weeks. Parieto-occipital fissure was the first fissure to develop and was present as a V-shaped indentation at 18 weeks and as a Y-shaped configuration by 21-22 weeks. Calcarine fissure was the next fissure to appear; it appeared as a dot by 18 weeks and developed into a V-shaped indentation by 20 weeks and as a Y-shaped configuration by 23 weeks. All fissures except cingulate sulci had appeared by 20 weeks, and calcarine sulci appeared later in the gestation by 21 weeks. Sylvian fissure initially appeared as a smooth surface and later underwent operculization to form obtuse and acute angulations with the adjacent temporal lobe by 20 and 24 weeks, respectively. Convexity sulci appeared later in gestation, beyond 25-26 weeks.ConclusionsUltrasonography, which is the commonest modality used in antenatal assessment of the fetus, can also be used to identify, familiarize, and provide a standard reference to assess normality of fetal sulcations. Neuronal migration disorders result in a wide spectrum of malformations of cortical development whose clinical manifestations include severe psychomotor retardation, developmental delays, motor deficits, seizures, and failure to thrive. Knowledge of normal development patterns of fetal cerebral sulci helps in early suspicion and detection of these cortical malformations, when present.

People with high empathy show increased cortical activity around the left medial parieto-occipital sulcus after watching social interaction of on-screen characters

People with high empathy interpret others' mental states in daily social interactions. To investigate their characteristics of social cognitive processing, we compared neuromagnetic activities between 20 males with high empathy and 23 males with low empathy while watching social interactions between two characters. Twenty stories of four-panel comic strips were presented; the first three panels described social interactions, and the last panel described empathic/nonempathic behaviors. People with high empathy exhibited increased cortical activity in the right occipital region, medial part of the bilateral superior frontal gyri, and right posterior insula while watching social interaction scenes, which suggests that they paid attention to others' faces and bodies, and inferred others' mental states. They also exhibited increased cortical activity in the left superior frontal gyrus while watching empathic behaviors. Moreover, they exhibited increased cortical activity in the region around the left medial parieto-occipital sulcus, which is related to self-projection, while passively watching both empathic and nonempathic endings. Taken together, these results suggest that people with high empathy pay attention to others and actively infer others' mental states while watching social interactions and that they reconstruct others' mental states and intentions through self-projection after watching a sequence of others' behaviors.

Visuomotor processing is altered after peripheral nerve damage in neuralgic amyotrophy.

Neuralgic amyotrophy is a common peripheral nerve disorder caused by autoimmune inflammation of the brachial plexus, clinically characterized by acute pain and weakness of the shoulder muscles, followed by motor impairment. Despite recovery of the peripheral nerves, patients often have residual motor dysfunction of the upper extremity, leading to persistent pain related to altered biomechanics of the shoulder region. Building on clinical signs that suggest a role for cerebral mechanisms in these residual complaints, here we show and characterize cerebral alterations following neuralgic amyotrophy. Neuralgic amyotrophy patients often develop alternative motor strategies, which suggests that (mal)adaptations may occur in somatomotor and/or visuomotor brain areas. Here, we tested where changes in cerebral sensorimotor representations occur in neuralgic amyotrophy, while controlling for altered motor execution due to peripheral neuropathy. We additionally explore the relation between potential cerebral alterations in neuralgic amyotrophy and clinical symptoms. During functional MRI scanning, 39 neuralgic amyotrophy patients with persistent, lateralized symptoms in the right upper extremity and 23 matched healthy participants solved a hand laterality judgement task that can activate sensorimotor representations of the upper extremity, across somatomotor and visuomotor brain areas. Behavioural and cerebral responses confirmed the involvement of embodied, sensorimotor processes across groups. Compared with healthy participants, neuralgic amyotrophy patients were slower in hand laterality judgement and had decreased cerebral activity specific to their affected limb in two higher-order visual brain regions: the right extrastriate cortex and the parieto-occipital sulcus. Exploratory analyses revealed that across patients, extrastriate activity specific to the affected limb decreased as persistent pain increased, and affected limb-related parieto-occipital activity decreased as imagery performance of the affected limb became slower. These findings suggest that maladaptive cerebral plasticity in visuomotor areas involved in sensorimotor integration plays a role in residual motor dysfunction and subsequent persistent pain in neuralgic amyotrophy. Rehabilitation interventions that apply visuomotor strategies to improve sensorimotor integration may help to treat neuralgic amyotrophy patients.

Relationship between Transient Cortical Blindness and Contrast Medium Leakage That Occurs after Endovascular Treatment of Posterior Circulation Aneurysms.

The mechanism of transient cortical blindness after endovascular treatment-a rare phenomenon-has not been elucidated; however, it is assumed to be related to contrast medium leakage (CML). We investigated the relationship between postoperative CML and cortical blindness in patients who underwent endovascular treatment for vascular lesions of posterior circulation. This retrospective cohort study included 28 patients who underwent endovascular treatment for posterior circulation aneurysms at our hospital between January 2014 and December 2018. Cerebral CT was performed immediately after endovascular treatment and 24 h later. CT images were retrospectively evaluated with special interest in the presence and distribution of leakage of the contrast medium (CM). Patients were classified into the following three groups based on CT findings: Group A, no CML (11 patients); Group B, unilateral CML (5 patients); and Group C, bilateral CML (9 patients). The posterior circulation aneurysms were located in the basilar artery in 13 (52.0%) cases, in the posterior cerebral artery in 1 (4.0%) case, and in the vertebral artery in 11 (44.0%) cases. There was no difference regarding the adjunctive technique used for endovascular treatment between the groups. Patients in Group C used a significantly larger amount of CM than those in the other two groups. A longer operation time was associated with a larger amount of CM used during treatment. VerifyNow assay revealed that the P2Y12 reaction unit was significantly lower in Groups B and C. Cortical blindness was transiently observed in 2 of 9 patients (22.2%) in Group C, both of which showed CML surrounding the bilateral parieto-occipital sulcus. Both patients with cortical blindness showed bilateral CML, both of which showed CML surrounding the bilateral parieto-occipital sulcus. The CM-induced blood-brain barrier disruption may be the cause of cortical blindness.

Abstract- Poster

1)Subdural hygromas are fluid collections within the subdural space that are clear or only slightly xanthochromic or blood tinged. They can be caused by mechanical trauma, meningeal or parameningeal infection, or venous congestion. Common presentation of SDH are fever, headache, nausea,vomiting, confusion.2)Here we report a 48 year old male who came with complaints of aggressiveness, forgetfulness, disturbed sleep. Further patient started developing dysarthria,inattention and memory was impaired.3)Neuroimaging- MRI brain showed subdural hygroma in bilateral fronto temporal parieto occipital region.4)Neurosurgery opinion obtained which is unremarkable5)Patient then started regaining his verbal fluency,memory and aggression settled in a span of 3 weeks.Although SDH is common among 1/3rd of patients with head injury/trauma,it is very rare that SDH presents with such features.References 1) SUBDURAL HYGROMA PRESENTING AS DEMENTIA WITH KLUVER-BUCY SYMPTOMS HARPREET S. DUGGAL, CHRISTODAY R.J.KHESS & S. HAQUE NIZAMIE2) Cognitive Impairment in the Elderly with Chronic Subdural Hematoma Hyun Hee Ye, MD, Jeong Ho Kim, MD, Yoon Suk Kim, MD,

Cranial and Cerebral Anatomic Key Points for Neurosurgery: A New Educational Insight.

The anatomy of both the skull and the brain offers many landmarks that could lead surgery. Cranial "craniometric" key points were described many years ago, and then, cerebral key points-along sulci and gyri-were detailed more recently for microneurosurgical approaches that can reach deep structures while sparing the brain. Nonetheless, this anatomic knowledge is progressively competed by new digital devices, such as imaging guidance systems, although they can be misleading. To summarize cranial and sulcal key points and their related anatomic structures to renew their interest in modern neurosurgery and help surgical anatomy teaching. After a literature review collecting anatomic key points of skull and brain, specimens were prepared and images were taken to expose skull and brain from lateral, superior, posterior, and oblique views. A high-definition camera was used, and images obtained were modified, superimposing both key points and underlying anatomic structures. From 4 views, 16 cranial key points were depicted: anterior and superior squamous point, precoronal and retrocoronal point, superior sagittal point, intraparietal point, temporoparietal point, preauricular point, nasion, bregma, stephanion, euryon, lambda, asterion, opisthocranion, and inion. These corresponded to underlying cerebral key points and relative brain parts: anterior and posterior sylvian point, superior and inferior rolandic point, supramarginal and angular gyri, parieto-occipital sulcus, and various meeting points between identifiable sulci. Stereoscopic views were also provided to help learning these key points. This comprehensive overview of the cranial and sulcal key points could be a useful tool for any neurosurgeon who wants to check her/his surgical route and make the surgery more "gentle, safe, and accurate."

Assessment of normal fetal cortical sulcus development

The aim of our study was to investigate the normal cortical sulcus development in fetuses without central nervous system abnormality with transabdominal ultrasonography. Our study was planned as a cross-sectional study in our clinic between November 2011 and October 2012. The study group was selected among pregnant women who applied to our hospital for routine antenatal follow-up. Singleton pregnancies, between 15th and 32nd gestational weeks, were included in the study. During the routine fetal ultrasonographic examination of these pregnant women, sylvian sulcus, parietooccipital sulcus, calcarine sulcus, and cingulate sulcus length measurements were taken and the correlation of these values with gestational week was evaluated. Three hundred and thirty-two patients were included in the study. Sylvian sulcus length, parietooccipital sulcus length, calcarine sulcus length, and cingulate sulcus length could be first measured respectively, at 15th, 17th, 17th and 25th gestational week. We found a positive correlation between gestational age and sylvian sulcus, parietooccipital sulcus, calcarine sulcus, and cingulate sulcus length measurements (p < 0.001). Sulcal development and cortical maturation can be evaluated prenatally with transabdominal ultrasonography of the central nervous system.

The posterior interhemispheric transparieto-occipital fissure approach to the atrium of the lateral ventricle: a fiber microdissection study with case series.

The surgical approach to the atrium of the lateral ventricle remains a challenge because of its deep location and close relationship to important neurovascular structures. We present an alternative and safer approach to lesions of the atrium using a natural pathway through the parieto-occipital fissure. We demonstrate this approach through cadaveric anatomical microdissection and a case series. Five formalin-fixed brain specimens (10 hemispheres) were dissected with the Klingler technique. Transillumination was used to show the trajectory of the approach in cadaveric specimens. Clinical data from five patients who underwent this approach were reviewed. This data included intraoperative ultrasound images, operative images, pre- and postoperative magnetic resonance imaging, MR tractography, and visual field examination. The parieto-occipital fissure is a constant, uninterrupted fissure that can be easily identified in cadavers. Our anatomical dissection study revealed that the atrium of the lateral ventricle can be approached through the parieto-occipital fissure with minor damage to the short association fibers between the precuneus and cuneus, and a few fibers of the forceps major. In our series, five patients underwent total resection of their atrial lesions via the posterior interhemispheric transparieto-occipital fissure. No morbidity or mortality was observed, and the disruption of white matter was minimal, as indicated on postoperative tractography. The postoperative visual fields were normal. The posterior interhemispheric transparieto-occipital fissure approach is an alternative to remove lesions in the atrium of the lateral ventricle, causing the least damage to white matter tracts and preserving visual cortex and optic radiation.

Altered Brain Structure and Spontaneous Functional Activity in Children With Concomitant Strabismus.

Strabismus occurs in about 2% of children and may result in amblyopia or lazy eyes and loss of depth perception. However, whether/how long-term strabismus shapes the brain structure and functions in children with concomitant strabismus (CS) is still unclear. In this study, a total of 26 patients with CS and 28 age-, sex-, and education-matched healthy controls (HCs) underwent structural and resting-state functional magnetic resonance imaging examination. The cortical thickness and amplitude of low-frequency fluctuation (ALFF) were calculated to assess the structural and functional plasticity in children with CS. Compared with HCs group, patients with CS showed increased cortical thickness in the precentral gyrus and angular gyrus while decreased cortical thickness in the left intraparietal sulcus, parieto-occipital sulcus, superior and middle temporal gyrus, right ventral premotor cortex, anterior insula, orbitofrontal cortex, and paracentral lobule. Meanwhile, CS patients exhibited increased ALFF in the prefrontal cortex and superior temporal gyrus, and decreased ALFF in the caudate and hippocampus. These results show that children with CS have abnormal structure and function in brain regions subserving eye movement, controls, and high-order cognitive functions. Our findings revealed the structural and functional abnormalities induced by CS and may provide new insight into the underlying neural mechanisms for CS.

Clinical spectrum of pediatric drug refractory epilepsy secondary to parieto-occipital gliosis

BackgroundParieto-occipital (PO) gliosis secondary to perinatal insult, is often associated with neurologic sequelae such as epilepsy, which can be drug resistant. ObjectiveTo evaluate the spectrum of epilepsy among patients presenting with seizures in association with PO gliosis and to determine factors that influence the development of epileptic encephalopathy (EE) in these patients. MethodsWe retrospectively evaluated patients aged < 16 years with drug refractory epilepsy and PO gliosis who underwent video electroencephalography (Video EEG). We evaluated the clinical, electrophysiological and radiological profile including treatment responsiveness of subjects with EE. ResultsOne hundred one patients (M: F=3:1) with mean age of onset of epilepsy at 28.9 ± 33.1 months were recruited into the study. Based on video EEG findings, Based on video EEG findings, the commonest type of focal onset ictus was tonic seizures with impaired awareness (n = 26, 29.9%). Myoclonic jerks (n = 20, 23%) were the commonest type of generalised onset seizures. Ictal onset from parieto occipital region were observed in 28 patients. Ictal onset from frontal, temporal and fronto temporal region were observed in 6 (6.8%), 7(7.9%) and 9 (8.9%) patients, respectively. Comparison of the seizure types and ictal onset among subgroups of patients with occipital gliosis, parieto-occipital gliosis and parieto-occipital with frontal gliosis revealed that the extent of gliosis did not significantly affect seizure semiology or ictal onset. EE was significantly associated with presence of neonatal seizures (p = 0.04), hypoglycaemia (p = 0.005), longer duration of ICU stay (Z score = −3.55, p < 0.001) and younger age of onset of seizures (Z score = - 2.97, p = 0.03). Eleven out of eighteen (64.7%) subjects with EE showed greater than 50% improvement in seizure frequency following three months of pulse intravenous methylprednisolone therapy. ConclusionsAmong subjects with PO gliosis on MRI, the seizure semiology is unaffected by laterality, radiologic extension beyond the occipital cortex or presence of ulegyria. Patients with PO gliosis can have florid interictal epileptiform discharges anteriorly and can have seizures with ictal onset from frontal and temporal region. Development of EE is strongly related to the age of onset of seizures, neonatal seizures, prolonged NICU admission, rather than the radiological findings. Subjects with EE and PO gliosis show good response to intravenous pulse methylprednisolone.

Anatomical variations of sulci in human fetal cerebrum and its clinical significance

Introduction and Aim: Appearance of sulci and its number in the fetal cerebrum is a signal of growth and development. Chronological appearance and symmetrical development of sulci corresponds to gestational age of fetus. Few sulci can be visualized in the prenatal period to judge the growth of fetus. Any change in chronological appearance, symmetry and number of sulci in fetal cerebrum is of prime importance. Materials and Methods: Hundred and six cerebral hemispheres of 53 fetal brains of different gestational ages were collected from MGM Hospital Kalamboli and Aurangabad after institutional ethical approval to study the pattern of sulci on both sides after fixing in 10% formalin. Results: In 6 (5.6 %) cerebral hemispheres variation in appearance of sulci was observed. It was noted that there is change in number of superior temporal sulcus (STS), superior frontal sulcus (SFS), parieto-occipital sulcus (POS), calcarine sulcus (CS) and occipitotemporal sulcus (OTS) on both the sides in 6 cerebral hemispheres. Remaining 100 cerebral hemisphere showed normal, symmetrical appearance and number of sulci. Conclusion: It was observed that the fetal cerebral hemispheres which showed variations in appearance and number of sulci were associated with mother having eclampsia.