Posterior fossa syndrome in a population of children and young adults with medulloblastoma: a retrospective, multicenter Italian study on incidence and pathophysiology in a histologically homogeneous and consecutive series of 136 patients.

INTRODUCTION: Posterior fossa syndrome (PFS) is a set of debilitating complications that can occur after surgery for posterior fossa tumors. This study aimed to assess the preoperative radiological and surgical risk factors for the onset of PFS in a histologically homogeneous population of children with medulloblastoma and compare it to a similar population of young adults. METHODS: Included patients underwent posterior fossa surgery for medulloblastoma at 11 Italian neurosurgical wards (2003-2019) and were referred to Fondazione IRCCS Istituto Nazionale dei Tumori in Milan (INT) for postoperative treatments. We collected patients' pre- and post-operative clinical, surgical and radiological data from the INT charts. To compare the distribution of variables, we used the Mann-Whitney and Fisher tests for continuous and categorical variables, respectively. RESULTS: 136 patients (109 children and 27 young adults) were included in the study. Among children, 29 (27%) developed PFS, and all of them had tumors at midline site with invasion of the fourth ventricle. Radiological evidence of involvement of the right superior (39% versus 12%; p = 0.011) or middle cerebellar peduncles (52% versus 18%; p = 0.002) seemed more common in children who developed PFS. Young adults showed an expected lower incidence of PFS (4 out of 27; 15%), that may be due to anatomical, physiological and oncological elements. CONCLUSIONS: This study confirmed some factors known to be associated with PFS onset and shed light on other debated issues. Our findings enhance an already hypothesized role of cerebellar language lateralization. The analysis of a population of young adults may shed more light on the often-neglected existence of PFS in non-pediatric patients.

Craniopagus: a proposed nursing care protocol.

Craniopagus is a rare condition in which the skulls of conjoined twins, and the neurovascular structures in their skulls, are incompletely separated. Separation surgery is complex and requires a range of skills and expertise, including from all the nursing teams involved. A multidisciplinary group of professionals in a tertiary paediatric care setting in Italy developed a comprehensive protocol for the nursing care of craniopagus twins in hospital, informed by the findings of a literature review and the expertise of its members. The protocol was applied to the management of a pair of craniopagus twins who successfully underwent separation surgery at the authors' hospital. The protocol describes the crucial role of nurses in the care of craniopagus twins and their families before, during and after separation surgery.

Contrast-induced encephalopathy and permanent neurological deficit: A case report and literature review.

BACKGROUND: Contrast-induced encephalopathy (CIE) is a rare condition that occurs after intravenous or intra-arterial contrast agent administration. Patients generally show different ranges of neurological deficits, which generally resolve themselves spontaneously within 24-48 h or in rare cases within 2 weeks. CASE DESCRIPTION: We report a case of CIE in a 54-year-old woman during retreatment for recanalization of communicating anterior artery aneurysm and with no history of allergic reaction to contrast agent. After the procedure, the patient developed right hemiplegia and complete aphasia; an MRI performed at 6 days excluded any signs of new ischemia and revealed a hyperintense signal on FLAIR sequences in the left cortical precentral gyrus corresponding to a hyperintense signal on DWI, suggesting a vasogenic edema. After 6 months, she clinically improved even if her previous neurological status was never restored while radiological findings did not change. CONCLUSION: According to the literature, many risk factors may play a role in the pathogenesis of CIE: we hypothesized that, among all of them, chronic hypertension and previous cerebral ischemic lesions were the most important in our case. Further studies are necessary to find the correlation between possible risk factors and neurotoxicity.

Role of aquaporins in hydrocephalus: what do we know and where do we stand? A systematic review.

INTRODUCTION: Glymphatic fluid circulation may be considered the lymphatic system of the brain and the main role of such system seems to be played by aquaporins (AQPs), a family of proteins which regulates water exchange, in particular AQP4 and 1. Alterations of glymphatic fluid circulation through AQPs variations are now emerging as central elements in the pathophysiology of different brain conditions, like hydrocephalus. This systematic review provides an insight about the role of AQPs in hydrocephalus establishment and compensation, investigating their possible role as diagnostic tools or therapeutic targets. METHODS: PubMed database was screened searching for the relevant existing literature in English language published until February 29th 2020, according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) Statement. RESULTS: A total of 40 articles met the inclusion criteria for our systematic analysis. AQP4 resulted the most studied water channel, followed by AQP1. The changes in cerebrospinal fluid (CSF), brain parenchyma and choroid plexus (CP) in different hydrocephalus type were analyzed. Moreover, important pharmacological interactions regarding AQP and molecules or conditions were discussed. A very interesting result is the general consensus on increase of AQP4 in hydrocephalic patients, unless in patients suffering from idiopathic normal pressure hydrocephalus, where AQP4 shows a tendency in reduction. CONCLUSION: AQP seem to play a central role in the pathophysiology of hydrocephalus and in its compensation mechanisms. Further studies are required to definitively establish their precise roles and their quantitative changes to allow their utilization as diagnostic tools or therapeutic targets.