A comparison of computed tomography and air ventriculography in diagnosis of progressive hydrocephalus of infancy.

We have compared the efficacy of computed tomography (CT) and air ventriculography (VGM) in the diagnostic evaluation of progressive nontumoral infant hydrocephalus where both examinations have been done without significant interventing time or treatment in infants under 12 months of age. CT alone was judged to be adequate for diagnosis and treatment 21 of 30 cases reviewed, provided that cerebrospinal fluid studies were available to complete diagnosis where necessary, and provided that the question of ventriculocisternal communication was not a factor in treatment selection. The ability to visualize cerebran aqueduct and 4th ventricle on CT was not always a reliable indicator of ventriculocisternal communication. CT was most adequate as the sole radiographic study in cases of myelodysplasia with Arnold-Chiari malformation, and in premature infants with intraventricular hemorrhage.     

A finite deformation model of infantile hydrocephalus

Clinical data obtained about intracranial pressure volume experiments abound in the literature. However, what is lacking is a proper interpretation of the data. A nonlinear hyperelastic model is proposed in this paper which is more realistic and simulates successfully the various states and stages of infantile hydrocephalus which have hitherto been considered puzzling. Strain energy function incorporating two and three constants have been employed to develop the constitutive equations and pressure-volume curves have been plotted for arbitrary values of the constants. The available clinical data can be employed through the proposed model to evaluate the status of hydrocephalus and also to arrive at suitable measures to relieve the intracranial pressure and ventricular dilatation.     

The effect of intracranial pressure on myelination and the relationship with neurodevelopment in infantile hydrocephalus

The effect of raised intracranial pressure (ICP), due to infantile hydrocephalus, on the process of myelination has been suggested in the literature. In this study 19 hydrocephalic infants were followed-up with anterior fontanelle pressure (AFP) measurement (assessment of ICP), MRI (assessment of the myelination process and the CSF volume), and neurodevelopmental testing (NDT). There was a high correlation (r=0.80) between the myelination and NDT scores. The size of the CSF volume showed a poor correlation with the mean AFP, the degree of myelination and the NDT scores. There was, however, a significant correlation between the mean AFP and the degree of myelination (r=0.67) and also between the mean AFP and the NDT scores (r=0.70). Longer-term follow-up (mean=27 months) showed a significant correlation between the early progress of myelination and later developmental level (r=0.78). Most of the children with a severely delayed myelination, preoperatively, showed a recovery of myelination following CSF drainage. It was concluded that: (1) raised ICP is related to developmental outcome, through the process of myelination; (2) the delay in myelination can be (partially) reversible; and (3) CSF volume is of minor importance regarding neurodevelopment.     

Ultrasonographic evaluation of infantile hydrocephalus before and after shunting

The authors present the results of a prospective study of 20 children with congenital or acquired hydrocephalus of nontumoral etiology and submitted to ventriculo-(or cyst-) peritoneal shunting with valve. The diagnosis was established by B-mode or real-time brain sonography, in association with another neuroradiological procedure (computed tomography, ventriculography with air or Dimer-X, cerebral angiography). Among the proposed measurements (cortical thickness, lateral ventricle height, III ventricle width and ventricular ratio) for pre- and postoperative comparison, the cortical thickness and the lateral ventricle height were the ones that changed significantly when analyzed by sonography. The routine use of brain sonography allowed the visualization of the ventricular catheter position and the diagnosis of complications, such as subdural collection, progressive enlargement of cysts, isolated IV ventricle, etc, even before symptoms arise. The authors conclude that sonography is easily performed, inexpensive and innocuous, and should be used routinely during the follow-up of children with hydrocephalus.     

The significance of morphological details for developmental outcome in infantile hydrocephalus

Sixty-four infants were selected for evaluation of hydrocephalus and associated cerebral anomalies on CT scan; initial findings are compared with follow-up results after shunt therapy and correlated with psychomotor development. Analysis indicates that initial high-grade cortical thinning, the capability of the brain to recover after CSF diversion, and size and number of associated cerebral anomalies can all be considered decisive factors in estimating prognosis in infantile hydrocephalus.     

The changing panorama of infantile hydrocephalus and cerebral palsy over forty years--a Swedish survey

The time trends and background of infantile hydrocephalus (IH) and cerebral palsy (CP) are surveyed. The changes in live birth prevalence, disability patterns, associated neuroimpairments and distribution of etiologies are analysed. Both the risk of IH and that of CP sharply increase with decreasing birth weight and gestational age. It is concluded that the remarkably enhanced survival of particularly very preterm infants, those at the highest risk of long-term morbidity, implies an increasing number of impaired children as long as the outcome of survivors is not drastically improved. The data presented are thought to be of relevance as to reconsideration of the effectiveness of perinatal care for preterm babies.     

Progressive tissue injury in infantile hydrocephalus and prevention/reversal with shunt treatment

Infantile hydrocephalus, despite shunt treatment, can leave children with a variety of persistent neurological deficits. A rat strain (H-Tx) with inherited fetal-onset hydrocephalus, is a natural model for the study of progressive tissue changes resulting from hydrocephalus and the effects of shunt placement. The cerebral cortex of rat pups has been studied at post-natal day 4 (P4), early stage hydrocephalus and equivalent to a third trimester human fetus, at P11, intermediate stage hydrocephalus and equivalent to a newborn human infant, and at P21 at advanced stage hydrocephalus. At P4, there is interstitial edema (increased water, sodium and chloride) and a non-reversible change in membrane lipids, particularly the phosphomonoesters. By P11, there are additional, non-reversible, changes in intracellular potassium and energy metabolites (ATP and phosphocreatine). At P21, the cells are severely damaged and further intracellular changes include a decrease in N-acetylaspartate (NAA) and loss of amino acids and many organic osmolytes. The interstitial edema is approximately 75% reversed after shunt treatment. The loss of energy metabolites, NAA and osmolytes can be prevented by early shunt treatment at P4, but the subsequent potassium loss is not prevented. Shunt at P11 does not prevent loss of NAA or aspartate, but osmolytes are normalized. It is concluded that persistent tissue damage is initiated by changes in cell membrane components leading to a decrease in energy metabolism and loss of cell homeostasis. A more complete understanding of the mechanisms involved could lead to new approaches for therapy.     

Assay of immune complexes in infantile hydrocephalus among Nigerians

The immune complexes in infantile hydrocephalic CSF in Nigerian children using a laser nephelometer were quantified. The values obtained were relatively low when compared with the serum levels. There was no evidence of selective admixture or of a breakdown of blood-brain-barrier (BBB). The low levels of immune complexes, when associated with implantation of shunt device for treatment of the hydrocephalus, may be a predisposing factor that can lead to overwhelming infection among this group of patients in a developing country like Nigeria. Between the hydrocephalic fluid and lumbar CSF, an IgG gradient was found.     

Pathology of the hippocampus in experimental feline infantile hydrocephalus

Hydrocephalus is responsible for many pediatric neurological deficits presumed to be caused by neocortical pathophysiology. Relatively little is known about the role of non-neocortical CNS structures in this condition. In the present work experimental infantile hydrocephalus produced by intracisternal kaolin injection was studied in a neonate kitten model. The hippocampal formation was processed for electron microscopy, and the neuropil of the CA3 region was examined in untreated, severely hydrocephalic and age-matched normal animals. Both macroscopically and microscopically the thickness of the hippocampus was not decreased. Hippocampal pyramidal neurons were found in varying stages of cytoplasmic densification, and dendritic and axonal processes exhibited hydropic cellular deterioration. The number of synaptic contacts was decreased. However, there was no indication of edematous extracellular space and the ependymal covering of the hippocampus was intact. The macroscopic structural integrity of the hippocampus, as well as the dendritic, axonal and synaptic alterations, suggest that the dark pyramidal neurons are the result of deafferentation, which may have profound effects on learning and memory.     

The value of multiple shunt systems in the treatment of nontumoral infantile hydrocephalus

A multiple shunt system has been employed in nine children with hydrocephalus combined with absent or insufficient communication with intracranial-filled spaces. The common feature of the different lesions to such a shunt system is a pressure difference, which can be adjusted by this procedure. There arise four general indications: (1) the uniform drainage of CSF spaces which do not communicate with each other; (2) the uniform drainage of CSF and other separate liquid filled intracranial spaces; (3) to obtain gradual and steady diminution of enormously dilated CSF or other fluid-filled spaces; (4) the use of both sides for shunting in cases with recurrent failures of a unilateral drainage. The post-operative efficacy of a multiple shunt can be proved by demonstrating evenly decreasing CSF and other fluid-filled cavities, and by equilibrium between their different pressures. Evaluation of possible shunt failure in a multiple system requires CT and ICP recordings.Presented at the 12th Annual Meeting of the International Society for Pediatric Neurosurgery     

Simultaneous endoscopic third ventriculostomy and ventriculoperitoneal shunt for infantile hydrocephalus

Objective We analyzed a series of consecutive hydrocephalic infants treated with implantation of a ventriculoperitoneal shunt (VPS) and endoscopic third ventriculostomy (ETV) simultaneously. Materials and methods Between 1995 and 2006, we treated the 111 hydrocephalic infants. Among those patients, 31 infants underwent VPS and ETV simultaneously, and 45 patients underwent only VPS. The ETV plus VPS group had 17 males and 14 females with a mean age of 6.32 months. The VPS only group consisted of 25 males and 20 females with a mean age of 4.43 months. There was no difference in etiology of hydrocephalus or clinical characteristics between the two groups. We compared shunt effectiveness by calculating the pre- and postoperative ventricular index and shunt failure rates during the follow-up period between the two groups. The follow-up period ranged from 6 to 140 months (mean, 53.23 months) in the ETV plus VPS group and from 6 to 148 months (mean, 75.98 months) in the VPS only group. The success rate was 83.9% (26 of 31) in the ETV plus VPS group and 68.9% (31 of 45) in the VPS only group. There were three infections and two shunt obstructions in the ETV plus VPS group versus eight obstructions, five infections, and one overdrainage in the VPS group. The preoperative and postoperative ventricular ratio of both groups showed statistically significant change (P < 0.000). Conclusion This simultaneous procedure could be the first choice of action for the hydrocephalic patients less than 1 year old.     

Computerized tomography in patients with neurocysticercosis with intracranial hypertension due to obstructive hydrocephalus: comparison with Dimer-X ventriculography

The authors reviewed the alterations observed on computerized tomography (CT) examinations of 16 patients with increased intracranial pressure and obstructive hydrocephalus due to cerebral cysticercosis. Plain radiograms of the skull were available in all cases and Dimer-X ventriculography in 12 cases. In 7 cases there were radiologic signs of increased intracranial pressure. CT scan showed normal cerebral parenchyma in 9 cases and low density areas, with various size, with or without surround contrast enhancement, and/or small calcifications in the parenchyma. Hydrocephalus was the only alteration observed in the ventricular system in the case that the examination was done before ventricular drainage. Ventriculography was analyzed in other paper and permitted to situate the obstruction, determine its morphological characteristics and identify occuping space lesions within the ventricles. Comparison between ventriculography and CT scan made in the same period evidence that the former gives best information about the ventricular system and that tomography gives additional information about the cerebral parenchyma. In conclusion, CT scan and ventriculography are investigations that complete each the other for evaluation and diagnosis of cerebral cysticercosis.     

Characteristics of brain tissue damage in kaolin-induced infantile rat hydrocephalus

Experimental hydrocephalus was induced by an intracisternal injection of 4% or 40% kaolin suspension in 2 days old Wistar rats. They were examined histologically and microangiographically 2 weeks after the injection of kaolin. Hydrocephalic rats were classified into 2 groups, severe hydrocephalic group A and mild hydrocephalic group B. In group A, a marked enlargement of the entire ventricular system with a thinning of the cerebral mantle was observed. On the other hand, the dilatation of the fourth ventricle was more pronounced compared with the other ventricles in group B. In group A, a spongy appearance of brain tissue was observed in the periventricular white matter accompanied with an intracerebral cavity. In these edematous areas, the lack of carbon black perfusion was apparent indicating an occurrence of microcirculatory disturbances. These microcirculatory disturbances and mechanical compression to the cerebral parenchyma may produce defective brain tissue (intracerebral cavity formation). The ependymal cell walls and subependymal glial cell layers were well preserved in spite of the damaged periventricular white matter. In group A, kaolin was present in the fourth ventricle and Sylvian aqueduct. Subependymal gliosis containing macrophages and newly produced blood vessels were observed in the region between the periventricular brain tissue and kaolin granules. These findings indicate that kaolin may produce changes in the ependymal cell and cerebral parenchyma as well as fibrosis and meningitis in the subarachnoid space.     

Electrophoretic pattern of cerebrospinal fluid proteins in non-neoplastic infantile hydrocephalus

Lumbar cerebrospinal fluid (CSF) from 28 non-neoplastic hydrocephalic children was studied for total protein and electrophoretic protein patterns. These were classified as normal, degenerative, transudative and gamma-globulinic according to Laterre. We found higher total CSF protein mean values than in normal cases with the same age and abnormal electrophoretic patterns in 72 % of the cases, of which degenerative was the most common (54 %). Gamma-globulinic and transudative patterns were found in 11 % and 7 % of the cases, respectively. Several factors which may explain the increase in the total CSF protein in infantile hydrocephalus are described: low age, ventricular block in the noncommunicating hydrocephalus, and probable passage of tissue proteins to the CSF from the damaged brain. the predominance of degenerative patterns may be explained by the enrichment of the CSF in tissue proteins resulting from the white matter damage provoked by the abnormal conditions of production, flow and absorption of the CSF in hydrocephalus.
Ventricular CSF was studied in four cases, and the results obtained are in agreement with the above-mentioned findings.