Posterior fossa tumors in children: An update and new concepts.

Background: Posterior fossa tumors account for approximately half of the central nervous system tumors in children. Major technological advances, mainly in the fields of molecular biology and neuroimaging, have modified their classification, leading to a more detailed description of these entities. Into the classic taxonomy, used for many years, new concepts have been incorporated at times eliminating or modifying former ones. Methods: A literature search was conducted in PubMed using the medical subject headings involving the five most common pediatric posterior fossa tumors: diffuse midline glioma, medulloblastoma, ependymoma, atypical teratoid/rhabdoid tumor, and pilocytic astrocytoma. Only English published articles in the past 11 years that provided technological, neuroimaging, and molecular biology insight into posterior fossa tumors in children were considered. Results: Substantial changes have been introduced in the nomenclature of pediatric posterior fossa tumors. Diffuse midline gliomas are named based on alterations in histone H3. Molecular rearrangements of medulloblastomas are more important in defining the prognosis than histological variants; therefore, these tumors are currently named based on their molecular subgroups. Posterior fossa ependymomas and atypical teratoid rhabdoid tumor classification have incorporated new groups based on different genetic profiles. Pilocytic astrocytoma has been placed in a new category that distinguishes circumscribed from diffuse entities. Conclusion: Advances in molecular biology and neuroimaging have substantially changed the way pediatric neoplasms are studied. The classical taxonomy has been modified leading to more accurate classifications that are based on the genetic alterations.

Long-tunneled versus short-tunneled external ventricular drain: a quasi-experimental study in a cohort of pediatric patients.

OBJECTIVE: The primary aim of this study was to compare external ventricular drain (EVD)-related infection rates and mechanical complications between long-tunneled EVDs (LTEVDs) with an interposed valve and short-tunneled EVDs (STEVDs) in a cohort of pediatric patients. The second objective was to compare hospital resources used for LTEVDs versus STEVDs in the same cohort of patients and the same study period. METHODS: The study consisted of a quasi-experimental investigation comparing a prospective group of patients who received LTEVDs with a retrospective (historic) cohort of patients treated with STEVDs. The prospective nonrandomized quasi-experimental protocol of the LTEVD cohort included patients who needed an EVD for more than 3 days. Data were recorded prospectively as the patients were added to the study, until reaching the sample size established by the protocol. The comparison group of the STEVD cohort was retrospectively collected from patients' records. Patients were included consecutively, from newest to oldest, starting with the last STEVD inserted at the authors' hospital until reaching the sample size established in the protocol. The inclusion and exclusion criteria for both groups were the same. RESULTS: One hundred thirty-four patients were included in this quasi-experimental study; there were 67 in each group. LTEVDs reduced the odds of having an EVD-related infection by 92% (OR 0.08, 95% CI 0.01-0.39; p = 0.002). Compared to STEVDs, the LTEVDs reduced by 69% the odds of having a CSF leak (OR 0.31, 95% CI 0.10-0.91; p = 0.03). Neither CSF blockage (OR 0.12, 95% CI 0.01-1.08; p = 0.06) nor displacement (OR 0.73, 95% CI 0.15-3.43; p = 0.69) showed a statistically significant difference between groups. More resources were allocated to STEVDs than to LTEVDs in most areas considered in this study. CONCLUSIONS: Compared to STEVDs, LTEVDs are a cost-effective and safe method to reduce EVD-related infection rates and other complications in pediatric patients. The authors believe that reducing the infection rate and complications and giving the patient more independence outweighs the additional costs that this new technique may entail.

Abdominal complications in patients with a ventriculoperitoneal shunt: proposal for management recommendations from a single pediatric tertiary center.

PURPOSE: The aim of this study was to describe our experience in the management of patients with ventriculoperitoneal shunt-related complications (abdominal pseudocyst, bowel-related complications, and ascites) and to propose treatment recommendations. MATERIAL AND METHODS: A retrospective descriptive study was conducted in patients with ventriculoperitoneal shunt-related abdominal complications seen between 2009 and 2019 at a tertiary-care pediatric center. Patients were classified according to their diagnosis into the following: group A (abdominal pseudocyst), group B (bowel-related complications), and group C (ascites). The following variables were studied in all three groups: age, sex, etiology of hydrocephalus, history of pyogenic ventriculitis, history of abdominal surgery, clinical presentation, presence of ventricular enlargement on computed tomography scan, abdominal ultrasonography, shunt series X-ray, cerebrospinal fluid cultures, urgent as well as elective surgical interventions, antibiotic treatment, length of hospital stay, follow-up, and outcome. RESULTS: Overall, 48 patients were analyzed: group A, n=29; group B, n=15; and group C, n=4. In all cases, surgical decision-making was based on symptom severity at the time of diagnosis, presence of ventricular enlargement on computed tomography scan, and cerebrospinal fluid culture results. In patients with positive cultures, the shunt system was removed, and an external ventricular drain was placed. In oligosymptomatic patients, cerebrospinal fluid culture results were awaited to define long-term treatment and in patients with ventricular enlargement or clinically difficult-to-treat symptoms, the distal catheter was exteriorized at the thoracic level. CONCLUSION: In patients with shunt-related abdominal complications, surgical management depends on symptom severity and/or whether infection is present at the time of diagnosis.

Baclofen pump with pre-brainstem catheter tip placement: technical note and case series.

PURPOSE: This study aims to describe a new baclofen pump implantation technique with pre-brainstem catheter placement and to demonstrate the benefits that this procedure has in treating spasticity and dystonia. METHODS: We described a new technique to place a baclofen pump catheter anterior to the brainstem. To illustrate the technique, we presented five patients with both spasticity and dystonia in whom conventional treatment was not effective. They each received a baclofen pump with a pre-brainstem catheter. We evaluated the results using the Ashworth scale for spasticity, the Barry-Albright scale for dystonia, and the PedsQL for quality of life assessment. Each patient was evaluated before a surgery and after 6 months of follow-up. RESULTS: There were statistically significant differences in all the physical examination evaluated areas using the Barry-Albright and modified Ashworth scales between the preoperative and the postoperative period. The same applies to the results of the PedsQL quality of life scale. CONCLUSION: We presented an innovative baclofen pump implantation technique with pre-brainstem catheter placement that could be a therapeutic alternative in patients with dystonia and spastic quadriparesis for whom conventional therapy is not effective.

Paraplejía compresiva de un año de evolución. ¿Es posible la recuperación mediante tratamiento quirúrgico? / Compressive paraplegia of one year of evolution. Is recovery possible by surgical treatment?

Introducción: La recuperación de la función motora luego de una lesión medular depende de varios factores como el nivel de la lesión, la extensión del daño, el tiempo de evolución y la edad del paciente. Mayormente la literatura hace referencia a la población adulta y poco existe publicado en pediatría. Objetivo: Reportar y enfatizar la utilidad de la cirugía en una paciente de 7 años con paraplejia por compresión tumoral de larga evolución con posterior recuperación neurológica. Presentación del caso: Paciente femenina de 7 años con paraplejía de larga evolución secundaria a una lesión neoplásica extradural torácica que presentó recuperación neurológica completa en el postoperatorio. Conclusión: Se reporta un caso clínico de una paciente con historia clínica de un año de paraplejia por compresión medular tumoral y recuperación completa luego de la remoción quirúrgica.

Introduction: The recovery of motor function after a spinal cord injury depends on several factors such as the level of the injury, the extent of the damage, the time of evolution and the age of the patient. Most of the literature refers to the adult population and there is little published in pediatrics. Objective: To report and emphasize the utility of surgery in a 7-year-old patient with long-standing tumor compression paraplegia with subsequent neurological recovery. Case presentation: 7-year-old female patient with long-standing paraplegia secondary to a thoracic extradural neoplastic lesion who presented complete neurological recovery in the postoperative period. Conclusion: A clinical case of a patient with a one-year medical history of paraplegia due to tumor spinal cord compression and complete recovery after surgical excision is reported.

Melanotic neuroectodermal tumor of infancy arising from the skull: report of an unusual case, review of the literature, and a diagnostic approach.

INTRODUCTION: Melanotic neuroectodermal tumor of infancy is a rare neoplasm mainly seen in children under 1 year of life. The most common location of the tumor is the maxilla followed by the cranial vault. Surgery is the treatment of choice and outcome mainly depends on extent of resection. OBJECTIVES: To report an atypical case of an 8-year-old patient with a melanotic neuroectodermal tumor of infancy, to review the cases with melanotic neuroectodermal tumor of infancy arising from the skull published over the last 13 years, and to provide a diagnostic approach that may allow recognition of a pattern in these rare neoplastic lesions. METHODS: A case is reported with a description of the clinical, radiological, surgical, and histopathological features. Additionally, the literature was reviewed to identify reports of patients with melanotic neuroectodermal tumor of infancy arising from the cranial vault and all cases published in PubMed over the last 13 years were included. Only studies that evaluated clinical, radiological, surgical, and histopathological findings were included. CONCLUSION: Melanotic neuroectodermal tumor of infancy is a rare entity that may present with unusual features, but nevertheless has an identifiable pattern that allows the tumor to be considered in the differential diagnosis of intracranial space-occupying lesions in children.