De la Torre GG, Martin A, Cervantes E, Guil R, Mestre JM. (2017)  Attention lapses in children with spina bifida and hydrocephalus and children with attention-deficit/hyperactivity disorder.  Journal of Clinical and Experimental Neuropsychology. 2017 Aug;39(6):563-573. doi: 10.1080/13803395.2016.1249828.

 

Abstract

Attentional lapses are usually defined as temporary and often brief shifts of attention away from some primary task to unrelated internal information processing. This study addressed the incidence of attention lapses and differences in attentional functioning in 30 children with attention-deficit/hyperactivity disorder (ADHD), 26 healthy children, and 29 children with spina bifida myelomeningocele and hydrocephalus (SBH). Assessments were conducted using computerized tonic and phasic attention tests, the Symbol Digit Modalities Test (SDMT), and the Trail Making Test Form B (TMT-B). The group with SBH differed from normal controls on cognitive measures of attention and executive functions. The ADHD group obtained lower scores than the SBH group and healthy children. ANOVA results showed that there was an effect of shunt revisions and shunt-related infections on neuropsychological performance. Lapses of attention together with reaction time may thus represent important factors for the understanding of cognitive deficits in SBH.

Fingerprint changes in CSF composition associated with different aetiologies in human neonatal hydrocephalus: glial proteins associated with cell damage and loss.

Naureen I, Waheed KA, Rathore AW, Victor S, Mallucci C, Goodden JR, Chohan SN, Miyan JA. (2013) Fingerprint changes in CSF composition associated with different aetiologies in human neonatal hydrocephalus: glial proteins associated with cell damage and loss. Fluids Barriers CNS. 2013 Dec 18;10(1):34. 

BACKGROUND:

In hydrocephalus an imbalance between production and absorption of cerebrospinal fluid (CSF) results in fluid accumulation, compression and stretching of the brain parenchyma. In addition, changes in CSF composition have a profound influence on the development and function of the brain and together, these can result in severe life-long neurological deficits. Brain damage or degenerative conditions can result in release of proteins expressed predominantly in neurons, astroglia, or oligodendroglia into the brain interstitial fluid, CSF and blood. Determination of such products in the CSF might be of value in diagnosing cause, aetiology and/or assessing the severity of the neurological damage in patients with hydrocephalus. We therefore analysed CSF from human neonates with hydrocephalus for these proteins to provide an insight into the pathophysiology associated with different aetiologies.

METHODS:

CSF was collected during routine lumbar puncture or ventricular tap. Samples were categorized according to age of onset of hydrocephalus and presumed cause (fetal-onset, late-onset, post-haemorrhagic or spina bifida with hydrocephalus). Glial fibrillary acidic protein (GFAP), myelin basic protein (MBP), vimentin and 2[prime], 3[prime]-cyclic nucleotide 3[prime]-phosphodiesterase (CNPase) were analysed through Western blotting of hydrocephalic CSF samples (n = 17) and compared with data from CSF of normal infants without neurological deficits (n = 8).

RESULTS:

GFAP was significantly raised only in CSF from post-haemorrhagic hydrocephalus while MBP was significantly raised in post-haemorrhagic and in spina bifida with hydrocephalus infants. Vimentin protein was only detected in some CSF samples from infants with late-onset hydrocephalus but not from other conditions. Surprisingly, CNPase was found in all neonatal CSF samples, including normal and hydrocephalic groups, although it was reduced in infants with late onset hydrocephalus compared with normal and other hydrocephalic groups.

CONCLUSIONS:

Apart from CNPase, which is an enzyme, the markers investigated are intracellular intermediate filaments and would be present in CSF only if the cells are compromised and the proteins released. Raised GFAP observed in post-haemorrhagic hydrocephalus must reflect damage to astrocytes and ependyma. Raised MBP in post-haemorrhagic and spina bifida with hydrocephalus indicates damage to oligodendrocytes and myelin. Vimentin protein detected in some of the late-onset hydrocephalic samples indicates damage to glial and other progenitors and suggests this condition affects periventricular regions. The presence of CNPase in all CSF samples was unexpected and indicates a possible novel role for this enzyme in brain development/myelination. Less CNPase in some cases of late-onset hydrocephalus could therefore indicate changes in myelination in these infants. This study demonstrates differential glial damage and loss in the developing human neonatal hydrocephalic brain associated with different aetiologies.

 

Free Article

Spatial navigational impairments in hydrocephalus.

Smith AD, Buckley MG. (2012)  Spatial navigational impairments in hydrocephalus. Cognitive Processing. 2012 Jul 18.

 

School of Psychology, University of Nottingham, University Park, Nottingham, NG7 2RD, UK, alastair.smith@nottingham.ac.uk.

Abstract

Whilst much is known about the neuropathological consequences of hydrocephalus, there have been comparatively few studies of the cognitive impairments associated with it. Studies using standardised tests of cognitive function have identified a general pattern of impairments, with patients exhibiting particular difficulty on tests of spatial memory and executive function. A strong prediction is that these deficits are likely to affect daily wayfinding behaviour, and we report a study of spatial and navigational abilities in a group of patients with hydrocephalus but without spina bifida. Participants completed a range of experimental tasks assessing spatial cueing behaviour, landmark memory and route-learning, and idiothetic path integration. This patient group was compared to a control sample matched on verbal, spatial, and intelligence measures, and hydrocephalus was found to be associated with relative impairments in each of the tasks. Patients exhibited reduced sensitivity to spatial cueing, less accurate route-learning, poorer memory for landmark objects, and less accurate spatial updating (with particular impairments in the calculation of heading). Overall, these data represent the first empirical demonstration of navigational impairments in hydrocephalus, and we suggest some of the cognitive, neural, and individual differences factors that may contribute to the pattern of performance reported.

PMID:22806680

 

Neuropsychological Functioning in Early Hydrocephalus: Review From a Developmental Perspective

Erickson K, Baron IS, Fantie BD. (2001) Neuropsychological Functioning in Early Hydrocephalus: Review From a Developmental Perspective Child Neuropsychol. 2001 Dec;7(4):199-229.


Children with hydrocephalus have deficits in several neuropsychological domains. The most notable are motor, visuoperceptual, and visuomotor function. These deficits are multiply determined and depend on the etiology and severity of the hydrocephalus to a large extent. Corpus callosum abnormalities resulting from stretching of callosal fibers and other cortical white matter tracts are implicated as contributory to these deficits. Enlarged ventricles and associated compression of posterior cortical areas also correlate with cognitive impairment. Distinguishing which cognitive domain negatively impacts on the child's functioning and which domains influence behavior in isolation or in combination has been the subject of numerous studies. Developmentally, we know little about the emergence of neuropsychological functioning in children with hydrocephalus. Study of the effects of hydrocephalus at different stages of development is useful to clinicians and researchers interested in the impact of diffuse neurophysiological damage on cognition in the developing brain. The medical and neuropsychological literature have begun to inform about these effects. The core deficits in hydrocephalus have yet to be explicated and a focus on investigations that answer these questions is required. This review summarizes the current knowledge about neurocognitive sequelae of hydrocephalus.

PMID: 16210211

Decreased activation and increased lateralization in brain functioning for selective attention and response inhibition in adolescents with spina bifida.

Ou X, Snow JH, Byerley AK, Hall JJ, Glasier CM. (2011) Decreased activation and increased lateralization in brain functioning for selective attention and response inhibition in adolescents with spina bifida. Child Neuropsychol. 2011 Dec 6.


We used functional magnetic resonance imaging to evaluate functional activity in the brain of adolescents with spina bifida when performing selective attention and response inhibition tasks. We then compared the results to that of age-matched controls. Our results showed that adolescents with spina bifida had decreased frontal and superior parietal activation and more apparently low involvement of left brain hemisphere during these tasks. Our results indicated activation deficits and possibly abnormal functional organization in adolescents with spina bifida and associated pathologies such as hydrocephalus.


PMID: 22145814

Cognitive and functional outcome in spina bifida-Chiari II malformation.

Jenkinson MD, Campbell S, Hayhurst C, Clark S, Kandasamy J, Lee MK, Flynn A, Murphy P, Mallucci CL.
Cognitive and functional outcome in spina bifida-Chiari II malformation.
Childs Nerv Syst. 2010 Dec 31.


PURPOSE: The long-term outcome in spina bifida-Chiari II-hydrocephalus complex is poorly understood. Traditional neurosurgical outcome measures are crude. Neuropsychological testing is increasingly important in outcome assessment. We investigated the health, disability, lifestyle and cognitive function in adults who had myelomeningocoele closure at birth.

METHODS: Adult patients under routine follow-up were assessed in a joint neurosurgery/neuropsychology clinic. Patients completed lifestyle questionnaires, the hydrocephalus outcome questionnaire (HOQ) and underwent cognitive testing. Clinical variables including number of shunt revisions, shunt infection and surgical decompression of foramen magnum, which may influence outcome, were investigated.

RESULTS: Twenty-one adults with a median age of 35 years were investigated. All had treated hydrocephalus, and eight had foramen magnum decompression for headache or progressive brainstem symptoms with stabilisation of symptoms in seven and improvement in one. Only eight patients were living independently, five were in paid employment and five work voluntarily. HOQ scores for cognitive function were lower (0.56 ± 0.20; mean ± standard deviation (SD)) than those for physical (0.64 ± 0.15) and social-emotional (0.65 ± 0.17) health. Cognitive function varied across the cohort with attention most severely affected (73.9 ± 17.0; mean ± SD). Repeated episodes of shunt malfunction or foramen magnum decompression were not associated with a worse cognitive function.

CONCLUSIONS: Despite intervention in childhood and adequate cerebrospinal fluid diversion the prognosis for independent living into adulthood remains poor. All patients have elements of cognitive impairment. Structural brain abnormalities may be more important determinants of cognitive outcome than shunt malfunction.



PMID: 21193992

Cognitive functions in children with myelomeningocele without hydrocephalus

Lindquist B, Uvebrant P, Rehn E, Carlsson G. (2009) Cognitive functions in children with myelomeningocele without hydrocephalus. Child’s Nervous System. 2009 Aug;25(8):969-75.

OBJECTIVE: The aim of this study was to explore the separate effects of myelomeningocele (MMC) and hydrocephalus on intelligence and neuropsychological functions in a population-based series of children.

MATERIAL AND METHODS: Of the 69 children with MMC born in 1992-1999 in western Sweden, nine did not develop hydrocephalus. Eight of them participated in this study and were compared with age- and gender-matched children with MMC in combination with hydrocephalus and with controls.

RESULTS: Children with only MMC had an IQ of 103 compared with 75 in those with hydrocephalus added to the MMC and they had significantly better immediate and long-term memory and executive functions. When compared with controls, they had difficulty with learning and executive functions, but when the two children with an IQ of less than 70 were excluded, those with only MMC performed just as well as the controls.

CONCLUSION: Hydrocephalus rather than MMC in itself appeared to cause the cognitive deficits found in children with MMC.

PMID: 19263057

Shunt complications in children with myelomeningocele: effect of timing of shunt placement. Clinical article.

Radmanesh F, Nejat F, El Khashab M, Ghodsi SM, Ardebili HE. (2009) Shunt complications in children with myelomeningocele: effect of timing of shunt placement. Clinical article. Journal of Neurosurgery: Pediatrics. 2009 Jun;3(6):516-20.

Department of Neurosurgery, Children's Hospital Medical Center, and Department of Biostatistics, Tehran University of Medical Sciences, Tehran, Iran.

OBJECT There has been controversy over whether CSF shunt insertion simultaneously with repair of myelomeningocele (MMC) might increase shunt-related complications. The purpose of this study was to evaluate shunt complication rates in patients who underwent concurrent MMC surgery and shunt placement and compare them to the rates in patients treated with shunt placement in a separate procedure.

METHODS The authors retrospectively reviewed the outcome of shunt placement in 127 patients with MMC who were followed up for >or=1 year after shunt surgery. In 65 patients shunt surgery was performed in a second operation after MMC repair and in 46 the 2 procedures were performed concurrently. In 7 patients shunt placement was the initial surgery, and in 9 it was the only procedure performed. The patients were evaluated for shunt complications.

RESULTS There was no statistically significant between-groups difference in age at which patients underwent shunt placement. The overall rates of shunt infection and shunt malfunction were 16.5 and 39.4%, respectively. There was a high rate of shunt infection and mortality in those patients treated with CSF shunting only. There was no statistically significant difference between complication rates in patients in whom the 2 procedures were performed concurrently and those who underwent separate operations.

CONCLUSIONS The order in which myelomeningocele repair and shunt placement were carried out did not have a significant effect on the rate of shunt complications. Thus, when indicated these procedures can be performed concurrently with a level of risk comparable to that associated with delayed shunt placement.

PMID: 19485738

Early shunt complications in 46 children with hydrocephalus.

Braga MH, Carvalho GT, Brandão RA, Lima FB, Costa BS. (2009) Early shunt complications in 46 children with hydrocephalus. Arquivos de neuro-psiquiatria. 2009 Jun;67(2A):273-7.

Department of Neurosurgery, Santa Casa de Belo Horizonte, MG, Brazil.

OBJECTIVE: To determine the causes of early shunt complications in 46 children with hydrocephalus. METHOD: A retrospective study was conducted on 46 children submitted to ventriculoperitoneal shunt surgery between February 2005 and February 2007. RESULTS: Thirteen (28%) patients presented complications, which were due to infection in 9 (69%) and to malfunction of the shunt system in 4 (31%).The mean number of surgical procedures performed on patients who presented complications was 2.8 per patient, with a total of 46 surgeries in this group. All patients with infectious complications were identified during their hospital stay. CONCLUSIONS: Infection was the most common complication. The infection rate was proportional to the length of hospital stay. All patients with hydrocephalus due to tumors or myelomeningocele presented complications. A higher incidence of infections was observed in children older than 2 years.

PMID: 19547822

Fetal surgery for myelomeningocele.

Hirose S, Farmer DL. (2009) Fetal surgery for myelomeningocele. Clinics in Perinatology. 2009 Jun;36(2):431-8, xi.

Division of Pediatric Surgery, Department of Surgery, Fetal Treatment Center, University of California, San Francisco, CA 94143-0570, USA. hiroses@surgery.ucsf.edu

Fetal intervention for myelomeningocele (MMC) may improve hydrocephalus and hindbrain herniation associated with the Arnold-Chiari II malformation and may reduce the need for ventriculoperitoneal shunting. As of now, there is little evidence that prenatal repair of MMC improves neurologic function. MMC is the first nonlethal disease under consideration and study for fetal surgery. As a result, potential improvements in outcome must be balanced with maternal safety and well-being, in addition to that of the unborn patient.

PMID: 19559329

Endoscopic third ventriculostomy: an outcome analysis of primary cases and procedures performed after ventriculoperitoneal shunt malfunction.

O'Brien DF, Javadpour M, Collins DR, Spennato P, Mallucci CL. (2005) Endoscopic third ventriculostomy: an outcome analysis of primary cases and procedures performed after ventriculoperitoneal shunt malfunction. Journal of Neurosurgery. 2005 Nov;103(5 Suppl):393-400.

Department of Neurosurgery, Royal Liverpool Children's Hospital NHS Trust, Liverpool, United Kingdom.

OBJECT: The authors analyzed the role of endoscopic third ventriculostomy (ETV) as a primary treatment for hydrocephalus and also as an alternative to shunt revision for malfunctioning and infected ventriculoperitoneal (VP) shunts.

METHODS: A retrospective analysis of clinical notes, operation records, and magnetic resonance imaging procedures before and after ventriculostomy was performed to determine the success or failure of ETVs in 170 patients who underwent a primary ETV and in 63 patients who underwent an ETV for shunt malfunction (secondary ETV). The patients' data were derived from an endoscopy database inaugurated in 1998. Of the 63 patients with shunt malfunctions, 49 patients (78%) had mechanical malfunction only and 14 patients (22%) had both infection and malfunction. Seventy-four percent (126 of 170) of patients in the primary ETV group and 70% (44 of 63) of patients in the secondary ETV had a successful outcome at the time of analysis. The success rate for ETVs in cases involving a mechanical shunt malfunction alone was 67% (33 of 49) compared with 79% (11 of 14) in those cases involving an infected shunt. The origin of the hydrocephalus in the primary and shunt malfunction groups was evaluated as a factor contributing to the success of the ETV. In the primary group, patients with a history of intraventricular hemorrhage (IVH) and meningitis as a cause for hydrocephalus had a poor rate of success after the ETV--27% (four of 15) and 0% (none of two), respectively. This pattern was not seen in the series involving shunt malfunction after the ETV, with 71% (five of seven) and 75% (three of four) of cases having a hydrocephalus origin of IVH and meningitis, respectively, in which a successful outcome was attained. A two-way mixed-model analysis of variance yielded a significant effect for origin (p = 0.011), a significant interaction between group and origin (p = 0.028), and a marginally nonsignificant effect of group (p = 0.0686). More than 95% of failures were evident within 1 month of the ETV in both groups. Complications were minimal in both groups, and there were no procedure-related deaths.

CONCLUSIONS: An ETV is a safe procedure with few complications and a high success rate in both primary and secondary groups. An ETV to address shunt malfunction, unlike a primary ETV, is not particularly origin specific. A bonus is its success in dealing with infected shunts. Most failures will be evident early, but long-term follow up is vital.

PMID: 16302610

First experiences with an adjustable gravitational valve in childhood hydrocephalus

Rohde V, Haberl EJ, Ludwig H, Thomale UW. First experiences with an adjustable gravitational valve in childhood hydrocephalus. Journal of Neurosurgery: Pediatrics. 2009 Feb;3(2):90-3.

Department of Neurosurgery, Georg-August University, Goettingen; and.

Object The goal of this report was to describe the authors' initial experiences with an adjustable gravity-assisted valve (GAV) called the ProGAV in treating childhood hydrocephalus. Methods The ProGAV was implanted in 53 children (29 boys and 24 girls, median age 7.3 years) with hydrocephalus of various origins. The ProGAV consists of a differential-pressure unit with adjustable opening pressures and a gravitational unit with a fixed opening pressure. Results The mean follow-up period was 15.2 months (range 6-44 months). The authors did not observe any valve-related complications. Four infections (7.5%) occurred, warranting the removal of the shunt. In 19 children, the opening pressure was changed at least once during the follow-up period, for underdrainage in 10, overdrainage in 8, and shunt weaning in 1, with substantial clinical improvement in 18 children. Overall, good clinical results were obtained in 47 (88.7%) of the 53 valve placements. Conclusions With an overall success rate of 88.7%, the first experiences with the ProGAV in childhood hydrocephalus are promising and justify its further use in the pediatric population.

PMID: 19278305

Neonatal high pressure hydrocephalus is associated with elevation of pro-inflammatory cytokines IL-18 and IFNg in cerebrospinal fluid

Sival DA, Felderhoff-Muser U, Schmitz T, Hoving EW, Schaller C, Heep A. Neonatal high pressure hydrocephalus is associated with elevation of pro-inflammatory cytokines IL-18 and IFNg in cerebrospinal fluid. Cerebrospinal Fluid Research. 2008 Dec 31;5(1):21.

ABSTRACT: BACKGROUND: In human neonatal high pressure hydrocephalus (HPHC), diffuse white matter injury and gliosis predispose to poor neuro-developmental outcome. The underlying mechanism for diffuse white matter damage in neonatal HPHC is still unclear. Analogous to inflammatory white matter damage after neonatal hypoxemia/ischemia, we hypothesized that pro-inflammatory cytokines could be involved in neonatal HPHC. If so, early anti-inflammatory therapy could ameliorate white matter damage in HPHC, before irreversible apoptosis has occurred. In HPHC and control neonates, we therefore aimed to compare cerebrospinal fluid (CSF) concentrations of IL18, IFNgamma and sFasL (interleukin 18, interferon gamma and apoptosis marker soluble-Fas ligand, respectively).

METHODS: In neonatal HPHC (n=30) and controls (n=15), we compared CSF concentrations of IL18, IFNgamma and sFasL using sandwich ELISA. HPHC was grouped according to etiology: spina bifida aperta (n=20), aqueduct stenosis (n=4), and fetal intra-cerebral haemorrhage (n=6). Neonatal control CSF was derived from otherwise healthy neonates (n=15), who underwent lumbar puncture for exclusion of meningitis.

RESULTS: In all three HPHC groups, CSF IL18 concentrations were significantly higher than control values, and the fetal intracranial haemorrhage group was significantly higher than SBA group. Similarly, in all HPHC groups CSF-IFNgamma concentrations significantly exceeded the control group. In both HPHC and control neonates, CSF FasL concentrations remained within the range of reference values.

CONCLUSION: Independent of the pathogenesis, neonatal HPHC is associated with the activation of the pro-inflammatory cytokines (IL-18 and IFNgamma) in the CSF, whereas CSF apoptosis biomarkers (sFasL) were unchanged. This suggests that anti-inflammatory treatment (in addition to shunting) could be helpful to preserve cerebral white matter.

PMID: 19117508

Williams H. The venous hypothesis of hydrocephalus. Medical Hypotheses. 2008;70(4):743-7. Epub 2007 Oct 4.

19 Elibank Road, Eltham, London SE9 1QQ, United Kingdom.

Pressure in the central nervous system (CNS) depends upon the volume of tissue that it contains. This includes blood, cerebrospinal fluid (CSF), nerves and any space occupying lesions. The dependency of pressure on volume arises because the CNS is confined by bone. Venous and CSF pressure is linked to overall pressure. Arterial pressure can increase in response to overall pressure to maintain arterial supply. Continuous arterial supply can be maintained because venous blood flows out of the CNS. Reduced volumes of arterial blood will enter the system if venous outflow is interrupted. Increase in CNS volume, as occurs with space occupying lesions, causes compression of veins. This may result in increased venous pressure and reduction in flow of blood out of the CNS. Cerebrospinal fluid (CSF) is extracellular fluid; its absorption back into the circulation is influenced by venous pressure. Any increased in CNS tissue volumes can therefore lead to CSF accumulation. This may then exacerbate the hydrocephalus by further increasing overall CNS volume. Free flow of CSF around the CNS facilitates venous drainage. Blockages to CSF flow can act like space occupying lesions. Chiari malformations, where the cerebellar tonsils obstruct the foramen magnum lead to reductions in CSF flow that can occur intermittently. This leads to impairment of venous drainage which may result in accumulation of CSF. The head or the spine can be affected together or separately. The manifestation of excess fluid accumulation is hydrocephalus and syringomyelia. The speed and origin of venous insufficiency influences the morphology of individual cases particularly with regard to lateral ventricle size. When pressure increases rapidly there may be little time for CSF accumulation. Oedema, compression of intracranial CSF spaces and cerebral ischaemia follows. When venous pressure is only slightly elevated CSF will accumulate and the manifestations of ischaemia may be less apparent, although ischaemia will be a feature of all instances of pathologically raised CNS pressure.

PMID: 17919832

A unifying hypothesis of hydrocephalus, Chiari malformation, syringomyelia, anencephaly and spina bifida

Williams H. A unifying hypothesis of hydrocephalus, Chiari malformation, syringomyelia, anencephaly and spina bifida. Cerebrospinal Fluid Research. 2008 Apr 11;5(1):7

ABSTRACT: This review is a modified version of the Casey Holter Memorial prize essay presented to the Society for Research into Hydrocephalus and Spina Bifida, June 29th 2007, Heidelberg, Germany. It describes the origin and consequences of the Chiari malformation, and proposes that hydrocephalus is caused by inadequate central nervous system (CNS) venous drainage. A new hypothesis regarding the pathogenesis, anencephaly and spina bifida is described. Any volume increase in the central nervous system can increase venous pressure. This occurs because veins are compressible and a CNS volume increase may result in reduced venous blood flow. This has the potential to cause progressive increase in cerebrospinal fluid (CSF) volume. Venous insufficiency may be caused by any disease that reduces space for venous volume. The flow of CSF has a beneficial effect on venous drainage. In health it moderates central nervous system pressure by moving between the head and spine. Conversely, obstruction to CSF flow causes localised pressure increases, which have an adverse effect on venous drainage. The Chiari malformation is associated with hindbrain herniation, which may be caused by low spinal pressure relative to cranial pressure. In these instances, there are hindbrain-related symptoms caused by cerebellar and brainstem compression. When spinal injury occurs as a result of a Chiari malformation, the primary pathology is posterior fossa hypoplasia, resulting in raised spinal pressure. The small posterior fossa prevents the flow of CSF from the spine to the head, as blood enters the central nervous system during movement. Consequently, intermittent increases in spinal pressure caused by movement, result in injury to the spinal cord. It is proposed that posterior fossa hypoplasia, which has origins in fetal life causes syringomyelia after birth and leads to damage to the spinal cord in spina bifida. It is proposed that hydrocephalus may occur as a result of posterior fossa hypoplasia, where raised pressure occurs as a result of obstruction to flow of CSF from the head to the spine, and cerebral injury with raised pressure occurs in anencephaly by this mechanism. The current view of dysraphism is that low central nervous system pressure and exposure to amniotic fluid, damage the central nervous system. The hypothesis proposed in this essay supports the view that spina bifida is a manifestation of progressive hydrocephalus in the fetus. It is proposed that mesodermal growth insufficiency influences both neural tube closure and central nervous system pressure, leading to dysraphism.

PMID: 18405364

Ventriculo-peritoneal shunt performance under hyperbaric conditions

Huang ET, Hardy KR, Stubbs JM, Lowe RA, Thom SR. Ventriculo-peritoneal shunt performance under hyperbaric conditions. Undersea & hyperbaric medicine. 2000 Winter;27(4):191-4.

A novice scuba diver with an implanted ventriculo-peritoneal (VP) shunt inquired about the performance characteristics of his shunt while diving. A literature search revealed no information regarding shunt performance under hyperbaric conditions. The manufacturer could not certify that the shunt would function under pressure. Therefore, four VP shunts were tested according to the manufacturer's testing protocol at 1 and 4 atm abs in a multiplace hyperbaric chamber. The pressure (in mm of H2O) required to establish flow through the shunts was recorded. Trials at 1 atm abs (n = 12) and 4 atm abs (n = 12) show that all shunts performed within the pressure range specified by the manufacturer.

PMID: 11419359

Hydrocephalus in children born in 1999-2002: epidemiology, outcome and ophthalmological findings

Persson EK, Anderson S, Wiklund LM, Uvebrant P. Hydrocephalus in children born in 1999-2002: epidemiology, outcome and ophthalmological findings. Child's Nervous System. 2007 Oct;23(10):1111-8. Epub 2007 Apr 12.

OBJECTIVE: The purpose of this study was to monitor incidence and outcome in children with hydrocephalus.

MATERIALS AND METHODS: This is a population-based prospective study of all the children with hydrocephalus born in western Sweden in 1999-2002. Etiological and clinical information was collected from records, neuroimaging and ophthalmological examinations. Comparisons with 208 children born in 1989-1998 were made.

RESULTS: The incidence was 0.66 per 1,000 live births, 0.48 for infantile hydrocephalus and 0.18 for hydrocephalus associated with myelomeningocele. The corresponding rates for 1989-1998 were 0.82, 0.49 and 0.33. Ventriculo-peritoneal shunt treatment was used in 42 of the 54 children and endoscopic third ventriculostomy in 12. Revisions were performed in 33 (61%). Neurological impairments were present in 63%, and they were more common in children born preterm than in those born at term. The radiological extent of parenchymal lesions correlated significantly with outcome. Ophthalmological abnormalities were found in 80%, including visual impairment in one third.

CONCLUSION: The incidence of post-haemorrhagic hydrocephalus in children born extremely preterm increased; a group running a high risk of neurological sequelae. Ophthalmological abnormalities were frequent and need to be assessed in all children with hydrocephalus. The high rate of morbidity and complications necessitates the further development of preventive and treatment methods.

PMID: 17429657

The transition from child to adult in neurosurgery

Vinchon M, Dhellemmes P. The transition from child to adult in neurosurgery.
Advances and Technical Standards in Neurosurgery. 2007;32:3-24.

The transition from child to adult is a growing concern in neurosurgery. Data documenting long-term follow-up are necessary to define this population's healthcare needs. In order to evaluate the problems posed by the child-to-adult transition in neurosurgery, we have studied the neurological, functional and social outcome of patients treated in our department for tumor of the central nervous system, hydrocephalus or myelomeningocele, and followed beyond the age of eighteen years. A large number of patients suffered from chronic ailments, either sequelae of their initial disease, or delayed complications of their initial treatment, with significant morbidity. The mortality during adulthood was 4.6% in the tumor group, 1.1% in the hydrocephalus group, and zero in the spina bifida group. The proportion of patients employed in normal jobs was 35.6, 18.7 and 11.5% for tumors, hydrocephalus and myelomeningocele respectively. IQ score and performance at school generally overestimated the capacity for social integration. Based on these data and on the available literature, we tried to identify the problems and devise solutions for the management of the transition from child-to-adulthood transition. Many problems present during childhood persist to adulthood, some of which are made more acute because of a more competitive environment, the lack of structures and inadequate medical follow-up. The transition from child to adult must be managed jointly by pediatric and adult neurosurgeons. More clinical research is required in order to precisely evaluate the problems posed by adult patients treated during childhood for the different neurosurgical diseases. Based on these data, a concerted trans-disciplinary approach is necessary, tailored to the specific needs of patients suffering from different diseases.

PMID: 17907472

Cerebral white matter and cognition in hydrocephalic children

Fletcher JM, Bohan TP, Brandt ME, Brookshire BL, Beaver SR, Francis DJ, Davidson KC, Thompson NM, Miner ME. Cerebral white matter and cognition in hydrocephalic children. Archives of Neurology. 1992 Aug;49(8):818-24.

Although children with hydrocephalus frequently show poor development of nonverbal cognitive skills relative to verbal skills, little is known about the neuropathologic correlates of these discrepancies. In this study, cerebral white-matter structures and lateral ventricles were measured from the magnetic resonance images of age-matched children with meningomyelocele, meningocele, and aqueductal stenosis and normal subjects. The volume of each lateral ventricle and the cross-sectional area of the corpus callosum and internal capsules were correlated with concurrent measures of verbal and nonverbal cognitive skills. The corpus callosum in the meningomyelocele and aqueductal stenosis groups was smaller. The lateral ventricles were larger, and the internal capsules were smaller, in all patient groups than in normal subjects. There were no differences in the size of the centra semiovale. Although verbal and nonverbal measures correlated positively with the size of the corpus callosum, the correlation was higher for nonverbal measures. Nonverbal measures correlated with the right, but not the left, lateral ventricle and with the area of the right and left internal capsules. Verbal measures correlated with the left, but not right, lateral ventricle and with the left, but not right, internal capsule. These results show a relationship between the corpus callosum and cognitive skills that is also influenced by hydrocephalus-related changes in the lateral ventricles and other cerebral white-matter tracts.

PMID: 1524514

Regional brain tissue composition in children with hydrocephalus. Relationships with cognitive development

Fletcher JM, McCauley SR, Brandt ME, Bohan TP, Kramer LA, Francis DJ, Thorstad K, Brookshire BL. Regional brain tissue composition in children with hydrocephalus. Relationships with cognitive development. Archives of Neurology. 1996 Jun;53(6):549-57.

OBJECTIVE: To determine whether children with shunted hydrocephalus show variations in regional brain tissue composition that relate to cognitive functions.

DESIGN: Nonequivalent control group.

PATIENTS AND METHODS: Magnetic resonance imaging (MRI) and cognitive skills assessments were obtained on 28 children, 6 to 9 years of age, with shunted hydrocephalus and 13 normal control subjects comparable in age, gender, ethnicity, and socioeconomic status. Three consecutive MRI slices below the vertex were segmented using a fuzzy clustering algorithm to separate pixels into gray matter, white matter, and cerebrospinal fluid (CSF) in quadrants representing left and right anterior and posterior brain regions. The cognitive skills assessments included the Wechsler Intelligence Scale for Children-Revised verbal and performance IQ scores, neuropsychological composites of language and visuospatial skills, a measure of visuomotor dexterity, and 2 measures of problem-solving abilities. The MRI data were analyzed in a group x tissue x hemisphere x region analysis of variance. Spearman rho correlations were computed within the hydrocephalus group between the MRI and cognitive measures.

RESULTS: Children with hydrocephalus showed reductions in overall gray matter percentages and corresponding increased CSF percentages that were more pronounced in posterior than anterior regions of both hemispheres. White matter percentages were reduced in children with hydrocephalus only in the left posterior quadrant. Correlations of posterior, but not anterior, CSF and gray matter percentages were significant with verbal and performance IQ scores and language, visuospatial, and visuomotor dexterity skills, but not with problem-solving abilities. Children with hydrocephalus who had proportionately greater posterior than anterior CSF percentages had significantly poorer visuomotor dexterity and visuospatial skills than did hydrocephalic children with proportionate CSF percentages.

CONCLUSION: Regional variations in brain tissue composition in children with shunted hydrocephalus correlate with a variety of cognitive and visuomotor functions.

PMID: 8660158