Integrated understanding of hydrocephalus — a practical approach for a complex disease

Most of childhood hydrocephalus are originating during infancy. It is considered to be a complex disease since it is developed on the basis of heterogeneous pathophysiological mechanisms and different pathological conditions as well as during different age groups. Hence, it is of relevant importance to have a practical concept in mind, how to categorize hydrocephalus to surgically better approach this disease. The current review should offer further basis of discussion on a disease still most frequently seen in Pediatric Neurosurgery. Current literature on pathophysiology and classification of pediatric hydrocephalus has been reviewed to integrate the different published concepts of hydrocephalus for pediatric neurosurgeons. The current understanding of infant and childhood hydrocephalus pathophysiology is summarized. A simplified concept based on seven factors of CSF dynamics is elaborated and discussed in the context of recent discussions. The seven factors such as pulsatility, CSF production, major CSF pathways, minor CSF pathways, CSF absorption, venous outflow, and respiration may have different relevance and may also overlap for the individual hydrocephalic condition. The surgical options available for pediatric neurosurgeons to approach hydrocephalus must be adapted to the individual condition. The heterogeneity of hydrocephalus causes mostly developing during infancy warrant a simplified overview and understanding for an everyday approach. The proposed guide may be a basis for further discussion and may serve for a more or less simple categorization to better approach hydrocephalus as a pathophysiological complex disease.

Pediatric Neurosurgery

This chapter focuses on pediatric neurosurgery. The first study compares the results of extended strip craniectomy versus subtotal calvarectomy with cranial vault remodeling for patients with sagittal craniosynostosis, while the second study tests the safety and efficacy of minimally invasive endoscopic strip craniectomy followed by helmet molding therapy in the treatment of infantile craniosynostosis. The next three studies determine the success of endoscopic third ventriculostomy (ETV) in the treatment of childhood hydrocephalus, evaluate the risk factors for cerebrospinal fluid (CSF) shunt infection following initial shunt replacement, and assess the efficacy of drainage, irrigation, and fibrinolytic therapy (DRIFT) for premature infants with posthemorrhagic ventricular dilatation. Meanwhile, the following set of studies identifies the genetic alterations related to the pathogenesis of pediatric medulloblastoma and discusses the effect of prolonged postoperative chemotherapy on the ability to delay the delivery of radiation in children younger than 3 years of age with malignant brain tumors. The following two studies investigate whether prenatal repair of myelomeningocele could result in better neurologic function compared with the standard postnatal repair and explore functional outcomes following selective posterior rhizotomy in children with cerebral palsy. The last study is of historical value and explore Cushing’s critical review of cerebellar medulloblastomas.

Central nervous system immune response in postinfectious hydrocephalus

Inflammation following neonatal infection is a dominant cause of childhood hydrocephalus in the developing world. Understanding this complex inflammatory response is critical for the development of preventive therapies. In 100 African hydrocephalic infants ≤3 months of age, with and without a history of infection, we elucidated the biological pathways that account for this inflammatory response. We integrated proteomics and RNA sequencing in cerebrospinal fluid, identifying gene pathways involving neutrophil, interleukin (4, 12, and 13) and interferon activity associated with this condition. These findings are required to develop strategies to reduce the risk of hydrocephalus during treatment of infection.