Chronic ("normal pressure") hydrocephalus in childhood and adolescence. A review of 16 cases and reappraisal of the syndrome

Endoscopic third ventriculostomy in children with chronic communicating congenital hydrocephalus: a single-center cohort retrospective analysis

OBJECTIVE

The aim of this study was to analyze the role of endoscopic third ventriculostomy (ETV) in the treatment of pediatric chronic communicating congenital hydrocephalus (CCCH).

MATERIAL AND METHODS

This retrospective study comprised a series of 11 children with CCCH treated with ETV. Data were recorded on gender, history, presenting symptoms, age at surgery, complications during surgery, clinical evolution, ETV survival, and follow-up period. Radiological variables including ventricular and cephalic diameters were also recorded to determine a series of ventricular indexes in magnetic resonance imaging (MRI) before and after the ETV procedure. The procedure was considered to be successful when there was clinical stability or improvement accompanied by a reduction in the radiological indexes in the postoperative control images, such that there was no need to place an extrathecal cerebrospinal fluid shunt.

RESULTS

Over a mean follow-up period of 35.8 months (range: 6-108 months) from the ETV procedure, three patients required shunt placement; one of these was due to early failure in an 8-month old girl, the only patient younger than 12 months in our series. The radiological indexes were reduced in all patients except for one of the cases of ETV failure. The mean ETV survival among the successful cases was 32.1 months (range: 6-108 months), whilst that of the failed cases was 16 months (range: 6-108 months).

CONCLUSION

Although studies with larger sample sizes are needed, ETV appears to be a promising option for the treatment of this type of patient with CCCH.

Genomic approaches to improve the clinical diagnosis and management of patients with congenital hydrocephalus

Congenital hydrocephalus (CH), characterized by incomplete clearance of CSF and subsequent enlargement of brain ventricles, is the most common congenital brain disorder. The lack of curative strategies for CH reflects a poor understanding of the underlying pathogenesis. Herein, the authors present an overview of recent findings in the pathogenesis of CH from human genetic studies and discuss the implications of these findings for treatment of CH. Findings from these omics data have the potential to reclassify CH according to a molecular nomenclature that may increase precision for genetic counseling, outcome prognostication, and treatment stratification. Beyond the immediate patient benefits, genomic data may also inform future clinical trials and catalyze the development of nonsurgical, molecularly targeted therapies. Therefore, the authors advocate for further application of genomic sequencing in clinical practice by the neurosurgical community as a diagnostic adjunct in the evaluation and management of patients diagnosed with CH.

Genomics of human congenital hydrocephalus

Congenital hydrocephalus (CH), characterized by enlarged brain ventricles, is considered a disease of pathological cerebrospinal fluid (CSF) accumulation and, therefore, treated largely by neurosurgical CSF diversion. The persistence of ventriculomegaly and poor neurodevelopmental outcomes in some post-surgical patients highlights our limited knowledge of disease mechanisms. Recent whole-exome sequencing (WES) studies have shown that rare, damaging de novo and inherited mutations with large effect contribute to ~ 25% of sporadic CH. Interestingly, multiple CH genes are key regulators of neural stem cell growth and differentiation and converge in human transcriptional networks and cell types pertinent to fetal neurogliogenesis. These data implicate genetic disruption of early brain development as the primary pathomechanism in a substantial minority of patients with sporadic CH, shedding new light on human brain development and the pathogenesis of hydrocephalus. These data further suggest WES as a clinical tool with potential to re-classify CH according to a molecular nomenclature of increased precision and utility for genetic counseling, outcome prognostication, and treatment stratification.

Reappraisal of Pediatric Normal-Pressure Hydrocephalus

While normal-pressure hydrocephalus (NPH) is most commonly diagnosed in older adulthood, a significant body of literature has accumulated over half a century documenting the clinical phenomenon of an NPH-like syndrome in pediatric patients. As in adult NPH, it is likely that pediatric NPH occurs due to a heterogeneous array of developmental, structural, and neurodegenerative pathologies, ultimately resulting in aberrant cerebrospinal fluid (CSF) flow and distribution within and around the brain. In this review, we aimed to systematically survey the existing clinical evidence supporting the existence of a pediatric form of NPH, dating back to the original recognition of NPH as a clinically significant subtype of communicating hydrocephalus. Leveraging emergent trends from the old and more recent published literature, we then present a modern characterization of pediatric NPH as a disorder firmly within the same disease spectrum as adult NPH, likely with overlapping etiology and pathophysiological mechanisms. Exemplary cases consistent with the diagnosis of pediatric NPH selected from the senior author’s neurosurgical practice are then presented alongside the systematic review to aid in discussion of the typical clinical and radiographic manifestations of pediatric NPH. Common co-morbidities and modern surgical treatment options are also described.

De Novo Mutation in Genes Regulating Neural Stem Cell Fate in Human Congenital Hydrocephalus

Congenital hydrocephalus (CH), featuring markedly enlarged brain ventricles, is thought to arise from failed cerebrospinal fluid (CSF) homeostasis and is treated with lifelong surgical CSF shunting with substantial morbidity. CH pathogenesis is poorly understood. Exome sequencing of 125 CH trios and 52 additional probands identified three genes with significant burden of rare damaging de novo or transmitted mutations: TRIM71 (p = 2.15 × 10^-7), SMARCC1 (p = 8.15 × 10^-10), and PTCH1 (p = 1.06 × 10^-6). Additionally, two de novo duplications were identified at the SHH locus, encoding the PTCH1 ligand (p = 1.2 × 10^-4). Together, these probands account for ∼10% of studied cases. Strikingly, all four genes are required for neural tube development and regulate ventricular zone neural stem cell fate. These results implicate impaired neurogenesis (rather than active CSF accumulation) in the pathogenesis of a subset of CH patients, with potential diagnostic, prognostic, and therapeutic ramifications.

Changes of cerebrospinal fluid protein concentrations and gait patterns in geriatric normal pressure hydrocephalus patients after ventriculoperitoneal shunting surgery

Normal pressure hydrocephalus (NPH) was the first type of dementia ever described that can be treated using ventriculoperitoneal shunting surgery. Three typical clinical symptoms of NPH include gait disturbance, progressive cognitive dysfunction, and urinary incontinence. Although there are articles that have discovered several cerebrospinal fluid (CSF) protein biomarkers associated with NPH; however, studies examining individual and total protein concentrations from the ventricular CSF before and after shunting surgery are lacking. This study used proteomics to calculate the CSF individual and total protein concentrations before, and one week, one month and three months after the shunting surgery. Parameters of cadence, step length, walking speed, and percentages of single- and double-limb support in a gait cycle were measured. Protein concentrations associated with anti-oxidation, aging, and in the prevention of neurotoxic agent production increased by at least 2-folds after the surgery, indicating that the brain may become less susceptible to neurodegeneration. These proteins were alpha-1B-glycoprotein, apolipoproteins A-1 & A-IV, prostaglandin-H2 D-isomerase, alpha-1-antitrypsin, and serotransferrin. In gait analysis, lower cadence, decreased double-limb support, longer step length, and increased single-limb support were observed after the surgery, indicating a more stable walking balance. These changes lasted for a period of at least 3 months. As a result, shunting surgery may be recommended for geriatric patients with confirmed diagnosis of normal pressure hydrocephalus.

Primary and Reversible Pisa Syndrome in Juvenile Normal Pressure Hydrocephalus

OBJECTIVE

To report a case of Pisa syndrome in a patient with idiopathic normal pressure hydrocephalus, who had never been exposed to psychotropic medications.

METHODS

A 26 years-old, Colombian, male patient, was referred because he had cognitive abnormalities, gait disturbances and urinary incontinence. This patient also displayed pleurothotonos. Neurofunctional evaluation of sensory and motor integration at peripheral and central nervous system levels were done.

RESULTS

Pisa syndrome disappeared after spinal tap drainage with further gait, balance and behavioral improvement. A brainstem-thalamocortical deregulation of the central sensory and motor programming, due to the chaotic enlargement of brain ventricles was thought to be the pathophysiological mechanism underlying this case.

CONCLUSION

NPH must not be longer considered as an exclusive geriatric disorder. Further, uncommon movement disorders may appear with this disorder, which should be carefully approached to avoid iatrogenic and deleterious pharmacological interventions.

Successful treatment of tremor by endoscopic third ventriculostomy in an adolescent with obstructive hydrocephalus due to tectal glioma: case report

Hydrocephalus presenting with movement disorder is very rare, especially in children. We present the case of a 16-year-old boy who presented with bilateral intention tremor and slowed speech as a result of obstructive hydrocephalus secondary to a tectal glioma. Treatment with endoscopic third ventriculostomy improved his symptoms. We review the literature regarding this unusual presentation of an otherwise common condition.

Anxiety responses and neurochemical changes in a kaolin-induced rat model of hydrocephalus

OBJECT

Hydrocephalus is a pathological enlargement of the ventricles of the brain, which can result from various diseases of the central nervous system. Patients with hydrocephalus frequently show motor abnormalities, such as abnormal gait and posture, as well as intellectual and emotional impairment. The present study was designed to investigate anxiety responses in rats with kaolin-induced hydrocephalus.

METHODS

A total of 26 Sprague-Dawley rats were used for this study. Hydrocephalus was induced in 14 Sprague-Dawley rats by injecting 0.1 ml of 20% kaolin solution into the cisterna magna; 12 rats were administered the same volume of saline in the same fashion and served as controls. Seven of the rats that were injected with kaolin and 6 of the rats injected with saline were killed 3 days after injection (Group 1); the remaining rats were killed 4 weeks after injection (Group 2) to evaluate effects related to acute and chronic hydrocephalus. The rats were tested in an elevated plus maze after induction of hydrocephalus by kaolin injection. After the animals were killed, brain sections were immunostained for cholecystokinin and neuropeptide Y. In addition, tyrosine hydroxylase immunoreactivity in the ventral tegmental area was evaluated by immunohistological staining.

RESULTS

The rats with acute hydrocephalus showed decreased entry into and spent less time in the open arms of the elevated plus maze as compared with the control rats. The hydrocephalic rats had significantly more cholecystokinin-immunoreactive neurons and fewer neuropeptide Y-immunoreactive neurons in their brains. In addition, hydrocephalus progress in this model was positively correlated with the anxiety response. The numbers of tyrosine hydroxylase-immunoreactive neurons were decreased significantly in the hydrocephalic rats as compared with the control rats.

CONCLUSIONS

These results suggest that the rat model of hydrocephalus is characterized by increased anxiety response and is associated with the functional impairment of the central dopamine system.

Using 'Catheter à Fentes' for Management of Childhood Hydrocephalus: A Prospective Study of Ninety-six Cases

OBJECTIVE

To evaluate the management of childhood hydrocephalus using the 'catheter à fentes' as a ventriculoperitoneal shunt.

MATERIALS AND METHODS

A prospective study from January 2003 to January 2004 was carried out in the Neurosurgery Department of the National Hospital Niamey (Niger-Republic). Ninety-six infants with hydrocephalus, between the ages of 1 to 22 months were treated with 'catheter à fentes' as a ventriculoperitoneal shunt.

RESULTS

Ninety-six infants with hydrocephalus, between the ages of 1 and 22 months were included in this study, over a period of 31 months; 53% of the infants were females. The symptoms evolved over three months in 89.55% of the cases (n = 85). Hydrocephalus was post-infective in 51% of the cases, associated with spina bifida in 32% of the cases, neonatal bleeding in 7.2% of the cases; brain abnormalities were found in 6.2%, and tumor in 3.1% of the cases. The head circumference was greater than 2SD in all cases; 87.53% of the infants had psychomotor retardation (less than 80 QD according to the Lezine score). Ventricular dilation was triventricular in 17.70% and tetra ventricular in 82.29% of the cases. 'Catheter à fentes' models of high pressure, medium pressure, and low pressure were used. Hydrodynamic complications (hyperdrainage, obstruction, underdrainage) occurred in 7.9% of the cases, and these were handled with simple observation in follow-up clinics. The average regression of head circumference three months postoperatively, for all the three models of 'catheter à fentes,' was 3.73 cm.

CONCLUSION

This study shows that the usage of 'catheter à fentes' for treatment of childhood hydrocephalus gives satisfactory results.

The syndrome of hydrocephalus in young and middle-aged adults (SHYMA)

OBJECTIVES

Currently, headache, nausea/vomiting, visual changes, and altered mental status are accepted as indications for the evaluation of hydrocephalus in children; while dementia, gait apraxia, and urinary incontinence remain indications in the elderly. The clinical presentation of hydrocephalus in young and middle-aged adults remains poorly described. Hence, middle-aged patients with mild gait, cognitive, or urinary symptoms unaccompanied by clear exam findings often remain undiagnosed and untreated.

METHODS

We report the clinical presentation, treatment, and outcomes of 46 adults (ages 16-55 years) presenting with congenital, acquired, or idiopathic hydrocephalus with imaging-documented ventriculomegaly and elevated CSF pressure.

RESULTS

Primary symptoms were related to gait (70%), cognition (70%), urinary urgency (48%), and headaches (56%). Eighty-four percent complained of impaired job performance. The exam findings were subtle or absent (no gait apraxia, minor gait changes in 42.9%, mildly abnormal Mini Mental State exams in only 14.3%, and incontinence in only 3.6%). Twenty-nine patients underwent ventriculoperitoneal (VP) shunting, and 11 endoscopic third ventriculostomy, of whom six subsequently required a VP shunt. Symptomatic improvement was observed in 93% of patients 16+/- 11 months after shunting (56% complete resolution, 37% partial resolution). Patients had been followed for their symptoms an average of 6 years (range, 1-30) prior to diagnosis.

DISCUSSION

We propose that there exists a clinically distinct syndrome of hydrocephalus in young and middle-aged adults (SHYMA) that comprises hydrocephalus of all etiologies. SHYMA is characterized by complaints of impaired gait, cognition, bladder control, and headaches, with a discrepancy between the prominence of symptoms and the subtlety of clinical signs. Despite the subtlety of clinical signs, CSF diversion treatment is effective at resolving symptomatology.

Association of learning and memory impairments with changes in the septohippocampal cholinergic system in rats with kaolin-induced hydrocephalus

OBJECTIVE

The septohippocampal cholinergic (SHC) system plays an important role in the maintenance of normal memory and learning. However, the fact that memory and learning impairments under hydrocephalic conditions are directly related to the SHC system is less well known. We investigated the relationships between pathological changes in SHC neurons and impairments in memory and learning among hydrocephalic rats.

METHODS

Rats with kaolin-induced hydrocephalus were prepared with injections of kaolin suspension into the cisterna magna. Learning and memory performance was assessed with the passive avoidance and Morris water maze tests. Ventricular sizes were measured for the lateral and third ventricles. Acetylcholinesterase and choline acetyltransferase immunostaining was performed to investigate degenerative changes in cholinergic neurons in the medial septum and hippocampus.

RESULTS

Hydrocephalic rats demonstrated significant learning and memory impairments in the passive avoidance and Morris water maze tests. Decreased hesitation times in the passive avoidance test and markedly increased acquisition times and decreased retention times in the Morris water maze test indicated learning and memory dysfunction among the hydrocephalic rats. The numbers of cholinergic neurons in the medial septum and hippocampus were decreased in the hydrocephalic rats. The decreases in choline acetyltransferase and acetylcholinesterase immunoreactivity were significantly correlated with enlargement of the ventricles.

CONCLUSION

Impairment of spatial memory and learning may be attributable to degeneration of SHC neurons. These results suggest that learning and memory impairments in rats with kaolin-induced hydrocephalus are associated with the dysfunction of the SHC system induced by ventricular dilation.

Rapid neurological deterioration associated with minor head trauma in chronic hydrocephalus

CASE REPORT

An 8-year-old developmentally normal boy (status: post third ventriculostomy and resection of posterior fossa low-grade glioma 4 years earlier and with known history of ventriculomegaly/arrested hydrocephalus) presented to the emergency room with vomiting and lethargy after a minor head trauma. Computed tomography scan of the head revealed no acute changes since previous studies. However, the patient's neurological status rapidly declined in the emergency room, where an emergency ventriculostomy demonstrated increased intracranial pressure. The patient's clinical condition improved over 24 h: he underwent placement of a ventriculoperitoneal shunt without complications and was discharged intact.

DISCUSSION

The pathogenesis of rapid neurological decline associated with minor head trauma in chronic hydrocephalus is reviewed.

Is normal pressure hydrocephalus a valid concept in 2002? A reappraisal in five questions and proposal for a new designation of the syndrome as "chronic hydrocephalus"

The authors question the current validity of the traditional concept of normal pressure hydrocephalus (NPH) as it was described by Adams and Hakim in 1965. The classic features of the disease are addressed. It is concluded that most of the historical statements made three decades ago need to be revised. Especially, the term "normal pressure" hydrocephalus probably does not match the actual manometric profile of patients with NPH. Similarly, the terms"curable"and "reversible" dementia are inadequate to designate the mental alterations of NPH. That NPH is non-specific to the adult population is also stressed, since it may be not uncommonly encountered in paediatrics, especially in an implanted shunt malfunction. The term "chronic hydrocephalus" without reference to cerebrospinal fluid pressure and to the age of the patient is proposed instead of NPH, which seems out of step with current knowledge of the pressure profile and with the diagnosis and decision making context in patients with so called NPH.

Neuropsychological findings in congenital and acquired childhood hydrocephalus

Hydrocephalus is an increase in cerebrospinal fluid volume that can be caused by a variety of etiologies. The most common connatal and acquired causes of hydrocephalus are spina bifida, aqueduct stenosis, and preterm low birthweight infants with ventricular hemorrhage. In general, the literature suggests mild neuropsychological deficits associated with hydrocephalus, which are predominant in visuospatial and motor functions, and other nonlanguage skills. Although the precise nature of the neuropsychological deficits in hydrocephalus are not completely known, several factors such as etiology, raised intracranial pressure, ventricular size, and changes in gray and white matter tissue composition as well as shunt treatment complications have been shown to influence cognition. In fact, the presence of complications and other brain abnormalities in addition to hydrocephalus such as infections, trauma, intraventricular hemorrhage, low birthweight, and asphyxia are important determinants of the ultimate cognitive status, placing the child at a high risk of cognitive impairment.

Cognitive changes after cerebrospinal fluid shunting in young adults with spina bifida and assumed arrested hydrocephalus

OBJECTIVES

To establish whether surgery can improve the neuropsychological functioning of young adult patients with spina bifida and apparent clinically arrested hydrocephalus showing abnormal intracranial pressure.

METHODS

Twenty three young adults with spina bifida and assumed arrested hydrocephalus (diagnosed as active or compensated by continuous intracranial pressure monitoring) underwent surgery. All patients received neuropsychological examination before surgery and 6 months later. Neuropsychological assessment included tests of verbal and visual memory, visuospatial functions, speed of mental processing, and frontal lobe functions.

RESULTS

Shunt placement in this subgroup of patients improves neuropsychological functioning, especially in verbal and visual memory and attention and cognitive flexibility.

CONCLUSIONS

Young adults with spina bifida and suspected non-functioning shunt or non-shunted ventriculomegaly should be carefully monitored to identify those who could benefit from shunting.

Magnetic resonance imaging and behavioral analysis of immature rats with kaolin-induced hydrocephalus: pre- and postshunting observations

The motor and cognitive dysfunction associated with hydrocephalus remains a clinical problem in children. We hypothesized that young rats with hydrocephalus should exhibit similar dysfunction and that the dysfunction should be reversible by shunting. Hydrocephalus was induced in 3-week-old rats by injection of kaolin into the cisterna magna. Rats were assessed by T2-weighted images obtained with a 7-T magnetic resonance device and by repeated behavioral testing including ability to traverse a narrow beam and ability to find a hidden platform in a water pool. Some of the rats underwent a shunting procedure 1 or 4 weeks after kaolin injection. Magnetic resonance images were used to measure ventricle size. They clearly demonstrated increased signal in periventricular white matter, which corresponded to increased brain water content. A flow-void phenomenon was observed in the cerebral aqueduct. Ability to traverse the beam did not correlate with the degree of ventriculomegaly. Ability to swim to the hidden platform demonstrated a progressive impairment of learning function which may have been accentuated by motor disability. When rats were shunted after 1 week, the behavioral dysfunction was prevented. Late shunting after 4 weeks was associated with gradual recovery of the behavioral disability which was not complete after 4 weeks. We conclude that early shunting is superior to late shunting with regard to behavioral dysfunction. High-resolution MR imaging shows features in hydrocephalic rats similar to those found in hydrocephalic humans.