Leat-associated seizures the possible role of EAAT2, pyruvate carboxylase and glutamine synthetase.

BACKGROUND: Drug-resistant epilepsy is a common condition in patients with brain neoplasms. The pathogenesis of tumor-associated seizures is poorly understood. Among the possible pathogenetic mechanisms, the increase in glutamate concentration has been proposed. Glutamate transporters, glutamine synthetase and pyruvate carboxylase are involved in maintaining the physiological concentration of glutamate in the intersynaptic spaces. In our previous research on angiocentric gliomas, we demonstrated that all tumors lacked the expression of the main glutamate transporter EAAT2, while the expression of glutamine synthetase and pyruvate carboxylase was mostly preserved. METHODS: In the present study, we evaluated the immunohistochemical expression of EAAT2, glutamine synthetase and pyruvate carboxylase in a heterogeneous series of 25 long-term epilepsy-associated tumors (10 dysembryoplastic neuroepithelial tumors, 7 gangliogliomas, 3 subependymal giant cell astrocytomas, 3 rosette forming glioneuronal tumors, 1 diffuse astrocytoma MYB- or MYBL1-altered and 1 angiocentric glioma). In order to evaluate the incidence of variants in the SLC1A2 gene, encoding EAAT2, in a large number of central nervous system tumors we also queried the PedcBioPortal. RESULTS: EAAT2 protein expression was lost in 9 tumors (36 %: 3 dysembryoplastic neuroepithelial tumors, 1 ganglioglioma, 3 subependymal giant cell astrocytomas, 1 diffuse astrocytoma MYB- or MYBL1-altered and 1 angiocentric glioma). Glutamine synthetase protein expression was completely lost in 2 tumors (8 %; 1 ganglioglioma and 1 diffuse astrocytoma MYB- or MYBL1-altered). All tumors of our series but rosette forming glioneuronal tumors (in which neurocytic cells were negative) were diffusely positive for pyruvate carboxylase. Consultation of the PedcBioPortal revealed that of 2307 pediatric brain tumors of different histotype and grade, 20 (< 1%) had variants in the SLC1A2 gene. Among the SLC1A2-mutated tumors, there were no angiocentric gliomas or other LEATs CONCLUSIONS: In conclusion, unlike angiocentric gliomas where the EAAT2 loss is typical and constant, the current study shows the loss of EAAT2 expression only in a fraction of the LEATs. In these cases, we may hypothesize some possible epileptogenic role of the EAAT2 loss. The retained expression of pyruvate carboxylase may contribute to determining a pathological glutamate excess unopposed by glutamine synthetase that resulted expressed to a variable extent in the majority of the tumors. Furthermore, we can assume that the EAAT2 loss in brain tumors in general and in LEATs in particular is more conceivably epigenetic.

Is endoscope-assisted strip craniectomy the future of metopic suture craniosynostosis treatment? An 11-year experience with 62 patients.

OBJECTIVE: Endoscopic mini-invasive treatment for sporadic trigonocephaly is becoming a widely accepted surgical treatment. In most centers this treatment is performed in association with postoperative helmeting. The aim of the present study was to review and report the authors' 11-year experience of endoscope-assisted metopic suturectomy for treatment of 62 trigonocephaly patients without helmet use. METHODS: For this retrospective study, clinical data of 62 consecutive pediatric patients (age 3-8 months) were obtained from the data bank of the "Anna Meyer" Children Hospital. These patients had been diagnosed with trigonocephaly (type II and III) and undergone surgery performed with a mini-invasive endoscopic technique during the period from January 2011 to January 2022. No helmet was used postoperatively in these patients, and they were evaluated through craniometric measurements, pre-/postoperative photographs, and parents' impressions, as well as thorough clinical examinations during follow-up appointments. RESULTS: The mean patient follow-up period was 6 ± 1.3 years. The female/male ratio was 1:2; 52% of the patients presented with type II trigonocephaly and the remaining patients with type III. The mean age at surgery was 153 ± 44 days (5 ± 1.5 months, range 3-8 months). In 92% of the patients the surgical outcome was defined as good to excellent. However, 4 patients presented with an unsatisfactory outcome, including 1 patient with a CSF collection requiring surgical repair 2 months after the first surgery and 1 patient who developed infection of the surgical wound and needed a second surgery. In the latter patient the outcome was evaluated as satisfactory, and no sequelae regarding the infection were encountered during follow-up. CONCLUSIONS: According to the authors' experience, endoscopic metopic suturectomy alone, without the use of a helmet, is a valid surgical option for trigonocephaly treatment, and its application can be considered in patients of older age groups (up to 8 months). Thus, in the right patient selection context, this technique represents the treatment of choice.

Loculated hydrocephalus: is neuroendoscopy effective and safe? A 90 patients' case series and literature review.

INTRODUCTION: Loculated hydrocephalus is a complex condition in which different non-communicating compartments form within the ventricular system due to different etiology, mainly intraventricular hemorrhage and infection. Since the end of the twentieth century, neuroendoscopy has been explored as a therapeutic option for loculated hydrocephalus with non-univocal results. METHODS: We performed a retrospective analysis of 90 patients who underwent endoscopic treatment for loculated hydrocephalus from January 1997 to January 2021 (mean age: 2 years, range 7-21). We included 37 (41.1%) children with multiloculated hydrocephalus, 37 (41.1%) with isolated lateral ventricle, 13 (14.4%) with excluded temporal horn, and 3 (3.3%) with isolated fourth ventricle. We compared our results with those available in literature. RESULTS: A mean of 1.91 endoscopic procedure/patient were performed (only one endoscopy in 42.2% of cases). Complications of neuroendoscopy and of shunt surgeries were recorded in 17 (18.9%) and 52 (57.8%) children, respectively. Twenty-six (28.9%) children were shunt-free at the last follow-up, 47.8% have only one shunt. DISCUSSION: The first goal of neuroendoscopy is to increase the rate of shunt-free patients but, when it is not possible, it aims at simplifying shunt system and reducing the number of surgical procedures. In our series, neuroendoscopy was able to achieve both these goals with an acceptable complication rate. Thus, our results confirmed neuroendoscopy as a valid tool in the long-term management of loculated hydrocephalus. Neuronavigation and intraoperative ultrasound could increase the success rate in cases with distorted anatomy.

Primary Intracerebral Alveolar Soft Part Sarcoma: Report of a Case and Review of the Literature.

Alveolar soft part sarcomas (ASPSs) are rare malignant tumors representing ∼1% of all soft tissue sarcomas. Most ASPS occurring in the central nervous system are metastases. In contrast, primary intracranial ASPSs are extremely rare and only 8 cases have been previously reported in English literature. Here, we report a case of primary alveolar soft part sarcoma in a 16-year-old female patient with no evidence of primary extracranial tumors. Histologically this case fulfilled the criteria of ASPS, and a molecular confirmation has been archived. To date, only 9 primary intracranial ASPS cases, including ours, have been reported in the literature. This report highlights the clinical and pathological characteristics, differential diagnosis, and molecular analysis of primary ASPS of the central nervous system.

Exclusive Neurogenic Bladder and Fecal Incontinency in an Achondroplasic Child Successfully Treated with Lumbar Foraminal Decompression.

INTRODUCTION: Achondroplasia is a genetic disorder characterized by defects in the development of endochondral bone resulting in skeletal abnormalities like stenosis of the foramen magnum and of the spine, shortened limb bones, and macrocephaly. Congenital spinal stenosis is frequent and due to premature fusion of the pedicles to the laminae. CASE PRESENTATION: We report a case of neurogenic bladder and fecal incontinence due to lumbar stenosis successfully treated with L1-L5 partial laminectomy and foraminotomy in a 7-year-old achondroplasic child. DISCUSSION/CONCLUSION: To our knowledge, this is the first case report of exclusive neurogenic bladder and fecal incontinence in an achondroplasic child. Neurogenic bladder and fecal incontinence without motor impairment may be early and exclusive clinical findings of lumbar stenosis in children with achondroplasia.

Optical coherence tomography significance in managing complex neurofibromatosis 2-related papilledema: Report of a case.

This case describes the strong utility of optical coherence tomography in multidisciplinary management of a complex case of type 2 neurofibromatosis.

Post-mortem histopathology of a pediatric brain after bilateral DBS of GPI for status dystonicus: case report and review of the literature.

PURPOSE: To investigate the effects of deep brain stimulation (DBS) electrodes on the brain of a dystonic pediatric patient submitted to bilateral DBS of the globus pallidus internus (GPI). METHODS: An 8-year-old male patient underwent bilateral DBS of GPI for status dystonicus. He died 2 months later due to multiorgan failure triggered by bacterial pneumonia. A post-mortem pathological study of the brain was done. RESULTS: At visual inspection, no grossly apparent softening, hemorrhage, or necrosis of the brain adjacent to the DBS lead tracts was detected. High-power microscopic examination of the tissue surrounding the electrode trajectories showed lymphocyte infiltration, astrocytic gliosis, microglia, macrophages, and clusters of multinucleate giant cells. Significant astrocytosis was confirmed by GFAP staining in the electrode site. The T cell lymphocyte activity was overexpressed with activated macrophages detected with CD3, CD20, CD45, and CD68 stains respectively. There was no gliosis or leukocyte infiltration away from the surgical tracks of the electrodes. CONCLUSION: This is the first post-mortem examination of a child's brain after bilateral DBS of GPI. The comparison with adult post-mortem reports showed no significant differences and confirms the safety of DBS implantation in the pediatric population too.

An incidentally detected third ventricle chordoid glioma.

Chordoid glioma is a rare low-grade tumor located in the third ventricle-hypothalamic region. Since its first report, 37 cases have been described in the literature. We report on an additional case that we considered significant because of its incidental detection and its uneventful surgical removal.