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Anatomy students are typically provided with two-dimensional (2D) sections and images when studying cerebral ventricular anatomy and students find this challenging. Because the ventricles are negative spaces located deep within the brain, the only way to understand their anatomy is by appreciating their boundaries formed by related structures. Looking at a 2D representation of these spaces, in any of the cardinal planes, will not enable visualisation of all of the structures that form the boundaries of the ventricles. Thus, using 2D sections alone requires students to compute their own mental image of the 3D ventricular spaces. The aim of this study was to develop a reproducible method for dissecting the human brain to create an educational resource to enhance student understanding of the intricate relationships between the ventricles and periventricular structures. To achieve this, we created a video resource that features a step-by-step guide using a fiber dissection method to reveal the lateral and third ventricles together with the closely related limbic system and basal ganglia structures. One of the advantages of this method is that it enables delineation of the white matter tracts that are difficult to distinguish using other dissection techniques. This video is accompanied by a written protocol that provides a systematic description of the process to aid in the reproduction of the brain dissection. This package offers a valuable anatomy teaching resource for educators and students alike. By following these instructions educators can create teaching resources and students can be guided to produce their own brain dissection as a hands-on practical activity. We recommend that this video guide be incorporated into neuroanatomy teaching to enhance student understanding of the morphology and clinical relevance of the ventricles.

Neurons are classified according to action potential firing in response to current injection. While such firing patterns are shaped by the composition and distribution of ion channels, modelling studies suggest that the geometry of dendritic branches also influences temporal firing patterns. Verifying this link is crucial to understanding how neurons transform their inputs to output but has so far been technically challenging. Here, we investigate branching-dependent firing by pruning the dendritic tree of pyramidal neurons. We use a focused ultrafast laser to achieve highly localized and minimally invasive cutting of dendrites, thus keeping the rest of the dendritic tree intact and the neuron functional. We verify successful dendrotomy via two-photon uncaging of neurotransmitters before and after dendrotomy at sites around the cut region and via biocytin staining. Our results show that significantly altering the dendritic arborisation, such as by severing the apical trunk, enhances excitability in layer V cortical pyramidal neurons as predicted by simulations. This method may be applied to the analysis of specific relationships between dendritic structure and neuronal function. The capacity to dynamically manipulate dendritic topology or isolate inputs from various dendritic domains can provide a fresh perspective on the roles they play in shaping neuronal output.

Objectives Cerebral hyperperfusion syndrome (CHS) is an uncommon but serious complication of carotid endarterectomy (CEA). Changes in mental status, headache, seizures and focal neurological deficits are common presenting symptoms[1][1]. The condition can occur up to 28 days after CEA. Impairment of cerebral vascular autoregulation has been implicated in the pathogenesis of the disease[2][2]. This study aims at presenting our experiences with CHS cases. Methods We conducted a retrospective review of the admissions to the neurology ward at the Canberra hospital and Calvary hospital, Bruce, ACT in 2016 to identify patients diagnosed with CHS. Individual patient records were then examined for patients’ demographics, symptomatology, examination findings, imaging findings and treatment outcomes. Results Two patients were identified from the registry data. The first patient was an 80-year-old man who presented 10 days after a left-sided CEA with right hemiparesis, seizures, hypertension and confusion. There was a significant amount of T2 hyperintensity in the left hemisphere on the MRI of the brain. An MRI perfusion scan showed significantly increased cerebral blood flow in the left middle cerebral artery territory. Despite seizure treatment and supportive cares, the patient succumbed to his illness. The second patient was an 86-year-old woman who had bilateral carotid stenosis (80%–90% on the left and 50%–69% on the right). On day 6 post left-sided CEA, she was hospitalised for seizures. She was intubated briefly due to significant agitation and treated with antiepileptic medications. MRI showed similar hyperintense lesions on the left hemisphere. There was no restricted diffusion. She made an uneventful recovery and was discharged home. Conclusions Our cases highlighted the significant morbidities and mortalities associated with CHS. Physician awareness can be important in the early recognition and treatment of this condition. [1]: #ref-1 [2]: #ref-2