Reinvestigating Tumor–Ventricle Relationship of Craniopharyngiomas With Predominantly Ventricular Involvement: An Endoscopic Endonasal Series Based on Histopathological Assessment

ObjectiveCraniopharyngiomas (CPs) predominantly involving the third ventricle were commonly termed “intraventricular” lesions. The aim of this study was to clarify the anatomical relationship between the tumor and the third ventricle by both surgical and histological investigation.MethodsA retrospective review of primarily resected CPs by endoscopic endonasal surgery was performed. CPs with predominantly ventricular involvement were selected for study inclusion by preoperative imaging. The surgical procedure of each case was reviewed. The wholly removed tumor specimens were histologically analyzed, in all cases, to investigate the tumor–third ventricle relationship using hematoxylin and eosin, immunochemical, and immunofluorescence staining.ResultsTwenty-six primary CPs predominantly involving the third ventricle were selected from our series of 223 CPs treated by endoscopic endonasal surgery between January 2017 and March 2021. Gross-total resection was achieved in 24 (92.3%) of 26 patients, with achievement of near-total resection in the remaining patients. A circumferential layer of stretched third ventricle floor was identified surrounding the tumor capsule, which could be peeled off easily from the ventricle floor remnants at most areas of the plane of tumor attachment. Some portions of the tumor capsule tightly adhered to the third ventricle floor were removed together with the floor. A breach of various size was observed at the third ventricle floor after tumor removal in most cases, the floor remaining intact in only two cases (7.7%). Histological examination on marked portions of tumor capsule showed that the pia mater was frequently detected at most of the tumor–brain interface, except at the antero-frontal border of tumor contacting with the third ventricle floor. At this point, a layer of gliosis with various thickness was observed between the tumor and the neural tissue of the third ventricle floor.ConclusionCPs with predominantly ventricular involvement should be considered as lesions with an extraventricular, epi-pia topography rather than “intraventricular” or “subpial” topography. Accurate understanding of the relationship between the third ventricle and such tumors would predict the circumferential cleavage plane of dissection, and remind neurosurgeons of performing dissection along the safe surgical plane to achieve total tumoral resection with minimizing hypothalamic damage.

Case Report on Subarachnoid Hemorrhage

Introduction: Subarachnoid haemorrhage (SAH) is caused by intracranial bleeding into the cerebrospinal fluid-filled space between the arachnoid and pia mater membranes on the surface of the brain. Patient History: The 65-year-old female patient was hospitalised to AVBR hospital in neurosurgery ward on December 25, 2020 with the chief complaints of headache, vomiting and episodes of seizures since three days. The patients had episodes of seizures on 21/12/2020 and 24/12/2020. The day later she was admitted to the Intensive Care Unit.she underwent all routine investigations like blood tests, and CT scan. After a thorough examination, the final diagnosis was subarachnoid haemorrhage. Past History: Patient did not have any history of communicable disease, asthma, tuberculosis, or any hereditary disease. Patient was COVID – negative and did not have any significant surgical history. Pharmacology: Patient was treated with proton pump inhibitor, antiemetic, antiepileptic, calcium channel blocker, stool softener analgesic and antipyretic. Management: Inj. Levipril 500 mg, Inj.pan40-40mg, cap.nimodipine 60mg every four hourly, Inj.emset 4 mg, Inj. Neomol 100 ml, Syp. glycerol 30 ml, Syp. Zincovit 2tsp and Tablet Dolo 650mg. Nursing Management: Patient’s vital sign (including blood pressure) and neurological status were monitored with bed rest, pain management and assessment of risk of bleeding. Conclusion: Patient was hospitalised with a threeday history of headache, vomiting, and episodes of seizures actively managed; condition satisfactory.

Subarachnoid Hemorrhage: A Case Report

We reported a case report of a 50-year-old woman with stroke hemorrhage due to subarachnoid hemorrhage with hypertensive urgency, left ventricular hypertrophy, and dyslipidemia. Subarachnoid hemorrhage indicates the presence of blood in the subarachnoid space between the pia mater and arachnoid mater which usually results from a ruptured cerebral aneurysm or arteriovenous malformation. The patient presents with decreased consciousness preceded by severe headache and projectile vomiting. In physical examination, we found hypertensive emergencies and positive meningeal signs, neck stiffness, and positive Brudzinski. CT scan shows bleeding in the pontocerebellar cistern and ventricular system. The patient was diagnosed with subarachnoid hemorrhage, intraventricular hemorrhage, and emergency hypertensive. The patient was hospitalized in the neurology ward of Ulin Hospital for 20 days with the management of antihypertensive, neuroprotectant, other symptomatic medications, and ventriculoperitoneal shunt surgery. The patient was then discharged home in a stable condition.

A Hyper-Viscoelastic Continuum-Level Finite Element Model of the Spinal Cord Assessed for Transverse Indentation and Impact Loading

Finite Element (FE) modelling of spinal cord response to impact can provide unique insights into the neural tissue response and injury risk potential. Yet, contemporary human body models (HBMs) used to examine injury risk and prevention across a wide range of impact scenarios often lack detailed integration of the spinal cord and surrounding tissues. The integration of a spinal cord in contemporary HBMs has been limited by the need for a continuum-level model owing to the relatively large element size required to be compatible with HBM, and the requirement for model development based on published material properties and validation using relevant non-linear material data. The goals of this study were to develop and assess non-linear material model parameters for the spinal cord parenchyma and pia mater, and incorporate these models into a continuum-level model of the spinal cord with a mesh size conducive to integration in HBM. First, hyper-viscoelastic material properties based on tissue-level mechanical test data for the spinal cord and hyperelastic material properties for the pia mater were determined. Secondly, the constitutive models were integrated in a spinal cord segment FE model validated against independent experimental data representing transverse compression of the spinal cord-pia mater complex (SCP) under quasi-static indentation and dynamic impact loading. The constitutive model parameters were fit to a quasi-linear viscoelastic model with an Ogden hyperelastic function, and then verified using single element test cases corresponding to the experimental strain rates for the spinal cord (0.32–77.22 s−1) and pia mater (0.05 s−1). Validation of the spinal cord model was then performed by re-creating, in an explicit FE code, two independent ex-vivo experimental setups: 1) transverse indentation of a porcine spinal cord-pia mater complex and 2) dynamic transverse impact of a bovine SCP. The indentation model accurately matched the experimental results up to 60% compression of the SCP, while the impact model predicted the loading phase and the maximum deformation (within 7%) of the SCP experimental data. This study quantified the important biomechanical contribution of the pia mater tissue during spinal cord deformation. The validated material models established in this study can be implemented in computational HBM.

Experimental study on disorders in the activity of macrophages in the acute period of different severities of cerebral stroke

BACKGROUND: The development of immunosuppression in the acute phase of cerebral stroke may lead to infectious and inflammatory complications. However, data on the functional activity of macrophages are insufficient to understand the pathogenesis of stroke. AIM: This study aimed to investigate the functional activity of macrophages in the acute period of experimental cerebral stroke (ECS) of different severities. MATERIALS AND METHODS: In an experimental study on 45 Wistar rats, the functional and spontaneous metabolic activity of macrophages in the spleen and abdominal cavity and the induced metabolic activity of peritoneal macrophages were evaluated through the reduction of nitro blue tetrazolium via spectrophotometry. The spontaneous and induced adhesive activity and the inhibition of the modified adhesive activity of peritoneal macrophages were examined via crystal violet staining by using a colorimetric method. ECS was modeled by the rotational movements of mandrel-knife inserted into the region of capsula interna (c.i.) on the left by guiding a needlecannula with the subsequent damage of vessels and the formation of mild (local incision of vessels in the region of c.i.), moderate (additional introduction of autologous blood in the area of c.i.), and severe (cutting of vessels from c.i. to pia mater with the subsequent introduction of autologous blood into the damaged area) hemorrhage. Data were evaluated in 72 h after different severities of ECS were modeled. RESULTS: In 72 h after ECS with different severities was modeled, the functional and spontaneous metabolic activity of splenic macrophages significantly decreased compared with those in the control group. The functional, spontaneous, and induced metabolic activity of peritoneal macrophages significantly reduced compared with those in the control group. The adhesive activity of peritoneal macrophages significantly increased compared with that of the control group. These disorders exacerbated in animal models with a more severe degree of stroke. CONCLUSION: In the acute period of ECS, the functional activity of macrophages decreased, whereas their adhesive activity increased. These phenomena enhanced in more severe models of stroke.

Central nervous system lesions caused by canine distemper virus in 4 vaccinated dogs

We examined the cerebellum and cerebrum of 4 vaccinated dogs, 3–60-mo-old, that displayed clinical signs of canine distemper virus (CDV) infection, and died 7–40 d after developing neurologic signs. The main histologic lesions were demyelination, gliosis, meningitis, perivascular lymphocytic cuffing, and inclusion bodies. These lesions were similar in all 4 cases regardless of the time since vaccination, except that meningoencephalitis and gliosis were subacute in 3 dogs and chronic in 1 dog. However, these differences did not appear to be related to their vaccination status. Immunohistologically, a CDV-positive immunoreaction was seen mainly in astrocytes, neurons and their axons, lymphocytes around and in the blood vessels of the pia mater and choroid plexus, ependymal cells of each ventricle, and the cells of the choroid plexus. The histologic and immunohistologic changes were similar in the cerebellum and cerebrum. The genetic characterization of the virus strains in 2 of these naturally occurring canine distemper cases confirmed that they were South American wild-type strains (Kiki and Uy251) belonging to the EU1/SA1 lineage. These strains are not included in the commercial CDV vaccines available in Uruguay.

Isolation and in vitro culture of primary pia mater cells

The meninges remain an unexplored area of neurobiology. These structures play host to dozens of morbid pathologies. This protocol provides a reliable way to identify and isolate pial cells from mice using robust markers of pial identity in mouse and human tissues. We describe a protocol for the extraction of pia mater cells from mice and their culture as primary cells in vitro. Using an array of transcriptomic, histological, and flow cytometric analyses, we identified Icam1 and Slc38a2 as two novel pia mater markers in vitro and in vivo. Our results confirm the fibroblastoid nature of pial cells and their ability to form a sheet-like layer that covers the brain parenchyma. To our knowledge, this is the first published protocol for the isolation, tissue culture, and marker identification of pial cells from mice. These findings will enable researchers in CNS barriers to describe pial cell functions in both health and disease.

An immunohistochemical study of lymphatic elements in the human brain

Almost 150 papers about brain lymphatics have been published in the last 150 years. Recently, the information in these papers has been synthesized into a picture of central nervous system (CNS) “glymphatics,” but the fine structure of lymphatic elements in the human brain based on imaging specific markers of lymphatic endothelium has not been described. We used LYVE1 and PDPN antibodies to visualize lymphatic marker-positive cells (LMPCs) in postmortem human brain samples, meninges, cavernous sinus (cavum trigeminale), and cranial nerves and bolstered our findings with a VEGFR3 antibody. LMPCs were present in the perivascular space, the walls of small and large arteries and veins, the media of large vessels along smooth muscle cell membranes, and the vascular adventitia. Lymphatic marker staining was detected in the pia mater, in the arachnoid, in venous sinuses, and among the layers of the dura mater. There were many LMPCs in the perineurium and endoneurium of cranial nerves. Soluble waste may move from the brain parenchyma via perivascular and paravascular routes to the closest subarachnoid space and then travel along the dura mater and/or cranial nerves. Particulate waste products travel along the laminae of the dura mater toward the jugular fossa, lamina cribrosa, and perineurium of the cranial nerves to enter the cervical lymphatics. CD3-positive T cells appear to be in close proximity to LMPCs in perivascular/perineural spaces throughout the brain. Both immunostaining and qPCR confirmed the presence of adhesion molecules in the CNS known to be involved in T cell migration.