Neuroendoscopic surgery in children: does age at intervention influence safety and efficacy? A single-center experience.

OBJECTIVE The aim of this study was to review the safety of pediatric intraventricular endoscopy across separate age groups and to determine whether intraventricular endoscopy is associated with an increased risk of complications or reduced efficacy in infants younger than 1 year. METHODS In this retrospective cohort study, 286 pediatric patients younger than 17 years underwent intraventricular endoscopy at Great Ormond Street Hospital between December 2005 and December 2014. The primary diagnosis, procedure, and complications were recorded. RESULTS Neuroendoscopic surgery was performed in 286 pediatric patients (51 neonates 0-6 months [Group 1]; 37 infants 6-12 months [Group 2]; 75 patients 1-5 years [Group 3]; 54 patients 5-10 years [Group 4]; and 69 patients ≥ 10 years [Group 5]; male/female ratio 173:113). The most common procedures included endoscopic third ventriculostomy (ETV) in 159 patients and endoscopic fenestration of intracranial cysts in 64 patients. A total of 348 consecutive neuroendoscopic procedures were undertaken. Nine different complications were identified, of which postoperative seizures (1.7%), CSF leak (3.1%), CSF infection (2.4%), and intracranial hemorrhage (1.7%) were the most common. Specifically, no significant difference in complication rate (11.9%) or infection rate (2.4%) was observed among age groups (p = 0.40 and p = 0.91, respectively). In addition, there were no perioperative deaths; 30-day mortality was 1.1%. After neuroendoscopy for CSF diversion (n = 227), a significantly higher rate of shunt insertion was observed in the youngest group (Group 1, 63.0%) when compared with older groups (Group 2, 46.4%; Group 3, 26.3%; Group 4, 38.6%; and Group 5, 30.8%; p = 0.03). Similarly, for patients who underwent ETV as their initial neuroendoscopic procedure or in combination with additional surgical interventions (n = 171), a significantly higher rate of shunt insertion was also observed within young infants (Group 1, 67.9%; Group 2, 47.6%; Group 3, 19.6%; Group 4, 27.3%; and Group 5, 23.3%; p = 0.003). CONCLUSIONS Intraventricular endoscopy is a safe neurosurgical intervention in pediatric patients of all ages, although it might be associated with increased shunt rates after endoscopic surgery, specifically ETV, in younger infants.

Moderate-Grade Germinal Matrix Haemorrhage Activates Cell Division in the Neonatal Mouse Subventricular Zone.

Precise temporal and spatial control of the neural stem/progenitor cells within the subventricular zone (SVZ) germinal matrix of the brain is important for normal development in the third trimester and the early postnatal period. The high metabolic demands of proliferating germinal matrix precursors, coupled with the flimsy structure of the germinal matrix cerebral vasculature, are thought to account for the high rates of haemorrhage in extremely- and very-low-birth-weight preterm infants. Germinal matrix haemorrhage can commonly extend to intraventricular haemorrhage (IVH). Because neural stem/progenitor cells are sensitive to microenvironmental cues from the ventricular, intermediate, and basal domains within the germinal matrix, haemorrhage has been postulated to impact neurological outcomes through aberration of normal neural stem/progenitor cell behaviour. We developed an animal model of neonatal germinal matrix haemorrhage using stereotactic injection of autologous blood into the mouse neonatal germinal matrix. Pathological analysis at 4 days postinjury showed high rates of intraventricular extension and ventricular dilatation but low rates of parenchymal disruption outside the germinal zone, recapitulating key features of human "Papile grade III" IVH. At 4 days postinjury we observed proliferation in the wall of the lateral ventricle with significantly increased numbers of transient amplifying cells within the SVZ and the corpus callosum. Analysis at 21 days postinjury revealed that cortical development was also affected, with increased neuronal and concomitant reduced oligodendroglial differentiation. At the molecular level, we showed downregulation of the expression of the transmembrane receptor Notch2 in CD133+ve cells of the SVZ, raising the possibility that the burst of precocious proliferation seen in our experimental mouse model and the skewed differentiation could be mediated by downregulation of the Notch pathway within the proximal/ventricular domain. These findings raise the possibility that Notch regulation plays a critical role in mediating the response of the neonatal SVZ to ischaemic and haemorrhagic insults.

Microfracture of a baclofen pump catheter with intermittent under- and overdose.

An 8-year-old boy with an implanted intrathecal baclofen pump presented with intermittent signs of baclofen under- and overdose. Pump interrogation, pump volumes, plain X-rays, catheter contrast fluoroscopy and CT of the intrathecal catheter tip were unremarkable. A microfracture of the extradural catheter was only seen at a magnification of x20 and confirmed by scanning electron microscopy. Symptoms resolved following replacement. Microfracture of the intrathecal catheter of baclofen pump systems may present puzzling symptomatology and be difficult to diagnose by conventional means.