Congenital Hydrocephalus: Role of Transplacental Myxovirus Infection

The definite etiology in most cases of congenital hydrocephalus still remains unknown. Many studies have been reported on the experimental hydrocephalus induced by viral infection other than TORCH (Toxoplasma, Other agents, Rubella virus, Cytomegalovirus and Herpes simplex type 1 and 2 viruses). Above all mumps virus induces a high frequency of hydrocephalus. Several pediatric cases of hydrocephalus after mumps virus infection have been reported. These cases are thought to be caused by ependymitis due to mumps virus infection. Clinical cases of congenital hydrocephalus possibly caused by intrauterine mumps or influenza virus infection are also accumulating. The definitive evidence of a teratogenic potential for mumps and influenza virus, however, has been obscure yet. Our experimental studies demonstrated that mumps and parainfluenza virus type 3 could induce hydrocephalus by destructive ependymal infection in suckling hamsters. However, the transplacental infection of these viruses was rare. These results show that myxoviruses such as mumps and parainfluenza virus have a strong affinity to ependymal cells, and then they cause resultant ependymal destruction. We suggest that when the placenta is impaired so severely that these viruses are able to pass through the placental barrier, maternal infection would cause the hydrocephalus to the infant.     

Rhombencephalosynapsis as a cause of aqueductal stenosis: an under-recognized association in hydrocephalic children

Background

Rhombencephalosynapsis is a rare genetic aberration characterized by variable vermian hypoplasia/aplasia in conjunction with united cerebellar hemispheres. Genetic defects in the isthmic organizer at the mesencephalic–metencephalic junction are presumably responsible for the associated aqueductal stenosis.

Objective

We performed a retrospective review of 20 children with rhombencephalosynapsis to evaluate for and emphasize the association of aqueductal stenosis and hydrocephalus.

Materials and methods

We retrospectively reviewed the MR and CT images of 20 children (0–11 years old) with rhombencephalosynapsis encountered at two academic children’s hospitals. Rhombencephalosynapsis spectrum severity was graded based on pre-existing literature. We analyzed examinations for ventriculomegaly and degree of aqueductal stenosis. The collicular distances were measured from the collicular apices. Imaging studies were also analyzed for malformations of cortical and cerebellar development.

Results

Thirteen of the 20 children (65%) with rhombencephalosynapsis presented with clinical or imaging evidence of hydrocephalus and aqueductal stenosis, principally involving the caudal cerebral aqueduct. All children with aqueductal stenosis had collicular fusion. All six children with complete rhombencephalosynapsis had aqueductal stenosis. The cerebral aqueduct varied from normal to stenotic in children with incomplete rhombencephalosynapsis. Corpus callosum dysgenesis was present in four children.

Conclusion

Aqueductal stenosis in the setting of rhombencephalosynapsis is an under-recognized cause of noncommunicating hydrocephalus. Our findings support the hypothesis that a defect involving the common gene(s) responsible for the differentiation and development of both the roof plate and midline cerebellar primordium at the mesencephalon/first rhombomere junction may be responsible for the association of aqueductal stenosis and rhombencephalosynapsis.     

Tight Junctional Damage in Experimental Mumps-Associated Hydrocephalus

Tight junctions in the central nervous system (CNS) are a major component of brain barriers including the blood-brain barrier (BBB) and blood-CSF barrier, which regulate solute entry and protect against invasion by microorganisms. In this study, we examined the breach of tight junctions in mumps virus-induced hydrocephalic brain in hamsters using antibodies to Laminin B1 chain and zonula occludentes (ZO-1) immuno-histochemistry, and evaluated the role of tight junctions in the pathogenesis of hydrocephalus after mumps virus infection.
In suckling hamsters intracerebrally inoculated with mumps virus, severe periventricular edema, ependymal cell loss, and ventricular dilation were observed. ZO-1-immunoreactive tight junctions in the hydrocephalic brains were severely damaged in the choroid plexus and ependyma, and in white matter capillaries as early as 3 days after inoculation. These changes were suspected to increase the permeability in blood-brain and blood-CSF barriers, leading to periventricular edema. We concluded that the pathologic features of mumps virus-induced hydrocephalus are intimately related to the breach of tight junctions.     

Congenital Hydrocephalus Induced in Rats by Prenatal Administration of Ethylenethiourea

Abstract: Pregnant Wistar rats were given a single i.p. injection of 30 mg/kg ethylenethiourea (ETU) on one of gestational days 8.5 to 20.5. After rearing to postnatal day 20, the offspring were sacrificed and their brains were excised. Numerous brains removed from the pups prenatally treated with ETU on any day from gestational days 12.5 to 20.5 showed dilatation of lateral ventricle in various degrees. Histological examination revealed forking and stenosis of third ventricle in these brains. Since the degree of the third-ventricular stenosis roughly corresponded to the degree of dilatation of lateral ventricle, this anomaly is considered to be the main cause of congenital hydrocephalus induced in rats by prenatal ETU-treatment. The embryological study showed that the ependymal lining of the third ventricle was partially denuded in the fetuses 24–48 hours after ETU-treatment, and also that the denuded ependymal lining was never repaired during the following gestational days; instead, the ventricular walls fused laterally in the area where the ependymal lining had been denuded.     

Visual pathway tumors and hydrocephalus

The authors evaluated the impact of hydrocephalus on the clinical picture of children with visua pathway tumor (VPT) with or without neurofibromatosis (NF).Charts of children with VPT treated in the authors' center since 1985 were retrospectively reviewed, and those with hydrocephalus were selected and summarized. Thirty-five children with VPT were found, of whom 20 had NF.Hydrocephalus was found in 4 children with NF (20% ) and in 5 without NF (33.3% ). In 6 ofthechildren, ventricular dilatation with signs of acute increased intracranial pressure already existed at the time of diagnosis and the hydrocephalus was shunted at this time. In the other 3 children, all with NF,the hydrocephalus resulted from slowly developing aqueductal stenosis, leading in 2 to severe visual acuity deterioration. The results suggest that in children with VPT and NF, hydrocephalus, and especially hydrocephalus resulting from aqueductal stenosis, is more frequent than in the general population of NF patients, and less frequent than in VPT patients without NF. The possibility of the indolent development of hydrocephalus should be borne in mind while following children with NF. The optic nerve, when already involved with a glioma, is more vulnerable to increased pressure. Thus, in children with VPT and NF, any ventricular dilatation should lead to a consideration of early shunting.     

VISUAL PATHWAY TUMORS AND HYDROCEPHALUS

The authors evaluated the impact of hydrocephalus on the clinical picture of children with visua pathway tumor (VPT) with or without neurofibromatosis (NF).Charts of children with VPT treated in the authors' center since 1985 were retrospectively reviewed, and those with hydrocephalus were selected and summarized. Thirty-five children with VPT were found, of whom 20 had NF.Hydrocephalus was found in 4 children with NF (20% ) and in 5 without NF (33.3% ). In 6 ofthechildren, ventricular dilatation with signs of acute increased intracranial pressure already existed at the time of diagnosis and the hydrocephalus was shunted at this time. In the other 3 children, all with NF,the hydrocephalus resulted from slowly developing aqueductal stenosis, leading in 2 to severe visual acuity deterioration. The results suggest that in children with VPT and NF, hydrocephalus, and especially hydrocephalus resulting from aqueductal stenosis, is more frequent than in the general population of NF patients, and less frequent than in VPT patients without NF. The possibility of the indolent development of hydrocephalus should be borne in mind while following children with NF. The optic nerve, when already involved with a glioma, is more vulnerable to increased pressure. Thus, in children with VPT and NF, any ventricular dilatation should lead to a consideration of early shunting.     

Regional Ependymal Upregulation of Vimentin in Chiari II Malformation,Aqueductal Stenosis,and Hydromyelia

Vimentin, glial fibrillary acidic protein (GFAP) and S-100 protein were studied by immunocytochemistry in the ependyma of patients with Chiari II malformations, congenital aqueductal stenosis, and hydromyelia. Paraffin sections of brains and spinal cords of 16 patients were examined, 14 with Chiari II malformations, most with aqueductal stenosis and/or hydromyelia as associated features, and 2 patients with congenital aqueductal stenosis without Chiari malformation. Patients ranged in age from 20-wk gestation to 48 years. The results demonstrated: 1) in the fetus and young infant with Chiari II malformations, congenital aqueductal stenosis, and hydromyelia, vimentin is focally upregulated in the ependyma only in areas of dysgenesis and not in the ependyma throughout the ventricular system; 2) GFAP and S-100 protein are not coexpressed, indicating that the selective upregulation of vimentin is not simple maturational delay; 3) vimentin upregulation also is seen in the ependymal remnants of the congenital atretic cerebral aqueduct, not associated with Chiari malformation; 4) in the older child and adult with Chiari II malformation, vimentin overexpression in the ependyma becomes more generalized in the lateral ventricles as well, hence evolves into a nonspecific upregulation. The interpretation from these findings leads to speculation that it is unlikely that ependymal vimentin is directly involved in the pathogenesis of Chiari II malformation, but may reflect a secondary upregulation due to defective expression of another gene. This gene may be one of rhombomeric segmentation that also plays a role in defective programming of the paraxial mesoderm for the basioccipital and supraoccipital bones resulting in a small posterior fossa. This interpretation supports the hypothesis of a molecular genetic defect, rather than a mechanical cause, as the etiology of the Chiari II malformation.     

Long-term outcome for endoscopic third ventriculostomy alone or in combination with choroid plexus cauterization for congenital aqueductal stenosis in African infants

Object The authors have previously reported on the overall improved efficacy of endoscopic third ventriculostomy (ETV) combined with choroid plexus cauterization (CPC) for infants younger than 1 year of age. In the present study they specifically examined the long-term efficacy of ETV with or without CPC in 35 infants with congenital aqueduct stenosis treated at CURE Children's Hospital of Uganda during the years 2001-2006. Methods Infants with congenital aqueductal stenosis were treated during 2 distinct treatment epochs: all underwent ETV alone, and subsequently all underwent ETV-CPC. Prospectively collected data in the clinical database were reviewed for all infants with an age < 1 year who had been treated for hydrocephalus due to congenital aqueductal stenosis. Study exclusion criteria included: 1) a history or findings on imaging or at the time of ventriculoscopy that suggested a possible infectious cause of the hydrocephalus, including scarred choroid plexus; 2) an open aqueduct or an aqueduct obstructed by a membrane or cyst rather than by stenosis; 3) severe malformations of the cerebral hemispheres including hydranencephaly, significant segments of undeveloped brain, or schizencephaly; 4) myelomeningocele, encephalocele, Dandy-Walker complex, or tumor; or 5) previous shunt insertion. The time to treatment failure was analyzed using the Kaplan-Meier method to construct survival curves. Log-rank (Mantel-Cox) and Gehan-Breslow-Wilcoxon tests were used to determine whether differences between the 2 treatment groups were significant. Results Thirty-five patients met the study criteria. Endoscopic third ventriculostomy alone was performed in 12 patients (mean age 4.7 months), and combined ETV-CPC was performed in 23 patients (mean age 3.5 months). For patients without treatment failure, the mean and median follow-ups were, respectively, 51.6 and 48.0 months in the ETV group and 31.2 and 26.4 months in the ETV-CPC group. Treatment was successful in 48.6% of the patients who underwent ETV alone, as accurately predicted by the Endoscopic Third Ventriculostomy Success Score (ETVSS), and in 81.9% of the patients who underwent ETV-CPC (p = 0.0119, log-rank test; p = 0.0041, Gehan-Breslow-Wilcoxon test; HR 6.42 [95% CI 1.51-27.36]). Conclusions Combined ETV-CPC is significantly superior to ETV alone for infants younger than 1 year of age with congenital aqueductal stenosis. The fact that the outcome for ETV alone was accurately predicted by the ETVSS suggests that these results are applicable in developed countries.     

Third ventricular ependymal cyst presenting with acute hydrocephalus

Ependymal cysts are generally located in the cerebral parenchyma but rarely found in the third ventricle. A 4-year-old boy presented with headache, vomiting, and upward gaze palsy. His consciousness gradually deteriorated in the course of 6 h. A magnetic resonance imaging study disclosed dilation of the lateral ventricle and a cystic mass in the third ventricle. We performed an endoscopic resection of the cyst wall. The cyst originated on the lateral wall of the third ventricle and obstructed the aqueduct. Histological examination confirmed a diagnosis of ependymal cyst. The patient recovered quickly and his headache and nausea disappeared. Third ventricular ependymal cysts are a rare cause of acute hydrocephalus but an important differential diagnosis. Their neuroendoscopic resection can resolve disturbances in cerebrospinal fluid circulation, is useful for cyst wall removal, and appears to be superior to shunt placement.     

Unusual mesencephalic developmental venous anomaly causing obstructive hydrocephalus due to aqueductal stenosis

Developmental venous anomalies (DVAs) are benign vascular malformations that rarely become symptomatic. They are anatomical variations of the venous drainage system and most are incidentally discovered. Mechanical (obstruction and compression of cerebral and neural structures) and flow-related pathological mechanisms have been described in rare cases of symptomatic DVAs. The authors present the case of a 10-month-old boy with a mesencephalic DVA compressing the aqueduct and causing occlusive hydrocephalus. Endoscopic inspection confirmed the venous malformation causing aqueductal stenosis. The authors successfully performed endoscopic third ventriculostomy, resulting in decrease in the size of the ventricles. At the 6-month follow-up after surgery, the patient had significantly progressed in his psychomotor development. One year postsurgery the patient is doing fine, with no neurological or developmental deficits.     

Diffuse choroid plexus hyperplasia: an under-diagnosed cause of hydrocephalus in children?

Hydrocephalus is a common neurological disorder in children and the result of a variety of causes. However, with the advancement of imaging modalities, particularly MRI, previously reported rarer causes of hydrocephalus in children are now being more readily appreciated. We report an 11-year-old boy with diffuse villous hyperplasia of the choroid plexus. He had a ventriculo-peritoneal (VP) shunt in-situ and a prior diagnosis from infancy of congenital aqueduct stenosis as the cause of his hydrocephalus. His current presentation was with further shunt dysfunction. CT and MRI demonstrated enlarged choroid plexuses but did not confirm aqueduct stenosis. CSF overproduction was demonstrated from the externalized ventricular drain. The enlarged choroid plexuses were surgically resected and histology confirmed choroid plexus hyperplasia. Identification of choroid plexus hyperplasia is important since the neurosurgical management of hydrocephalus is not VP shunt insertion, but resection of the hyperplastic choroid plexus.     

Non-tumoral neonatal hydrocephalus. Results of surgical treatment in the first month of life]

Two hundred eight patients with non-tumoral congenital hydrocephalus underwent CSF shunting below the age of one month. Ultrasonography was the most frequently utilized tool; hydrocephalus was recognized during pregnancy in 52% of the cases. Hydrocephalus was associated with myelomeningocele in 97 infants; in 38 subjects ventricular dilation was secondary to aqueductal stenosis. Post-hemorrhagic and post-infective hydrocephalus accounted for only 20 and 13 cases respectively. At the follow-up observation, a normal psychomotor development was recorded in 67.3% of the cases. Seventeen patients died. CSF infection was the most common cause of death (41%); in 6 patients the exitus was determined by the natural evolution of congenital associated malformations. Shunt revision did not influence the morbidity and the mortality significantly. On the other hand, CSF infections appeared to influence the prognosis negatively. In our experience, the prognosis of hydrocephalus operated on in the first month of life does not differ from that of hydrocephalus operated on late in life.     

Candida Meningitis Causing Aqueductal Stenosis Following Parenteral Nutrition in An Infant With Meconium Peritonitis

Meconium peritonitis of unknown aetiology was observed in a pair of twins who were diagnosed antenatally by echogram to have ascites. Both the twins had respiratory problems, and one twin died soon after birth. The other twin had intestinal perforation and required parenteral nutrition till the age of 27 days. At the age of 70 days she developed hydrocephalus which was found to Le due to aqueductal stenosis secondary to Candida infection.     

Bobble-head doll syndrome

A new case of Bobble-head doll syndrome with aqueductal stenosis is presented in a 14 year-old boy. Ventriculocisternostomy performed 8 years after the onset of the abnormal movement resulted in moderate reduction of the head bobbling. Twenty-two cases were found in a review of the literature. In all cases there was a chronic slowly progressive hydrocephalus with usually a cyst of the third ventricle; aqueductal stenosis was less frequent. When recorded, psychomotor development was impaired. Treatment is neurosurgical. Pathogenesis remains unknown.     

Congenital intracerebral teratoma: a rare differential diagnosis in newborn hydrocephalus

Congenital hydrocephalus is caused by a broad spectrum of underlying disorders. In the majority of cases it is due to aqueductal stenosis and other distinct congenital anomalies, like Arnold-Chiari malformation. Nevertheless, in the differential diagnosis rare conditions such as cerebral malignancies must also be considered. We present two cases of congenital intracerebral teratoma as a differential diagnosis in congenital obstructive hydrocephalus. A teratoma is suggested when a rapidly growing hydrocephalus with a central calcified and vascularized mass is found sonographically. Regular cerebral structures usually cannot be detected. Early diagnosis in such cases is of clinical importance as the prognosis of congenital intracerebral teratoma is generally very poor. Received: 22 May 1996 Accepted: 10 August 1996     

Aqueductal stenosis presenting as isolated tremor: case report and review of the literature

Essential tremor is rare in children, particularly in the absence of a significant family history. We report the case of a child with compensated hydrocephalus secondary to aqueductal stenosis whose sole presenting symptom was tremor. An otherwise healthy 6-year-old male developed a fine hand tremor, which over the course of 4 years both increased in intensity and spread to involve the lower limbs and head. After an MRI had confirmed hydrocephalus due to aqueductal stenosis, the patient underwent an endoscopic third ventriculostomy. His tremor improved markedly, but did not completely resolve. Occult hydrocephalus should be considered in the differential diagnosis of new-onset tremor. Progression of the tremor should halt with treatment of the hydrocephalus, and clinical improvement may be seen.     

A longitudinal study of post-haemorrhagic ventricular dilatation in the newborn.

Two hundred and two consecutive admissions to a regional neonatal unit were scanned by real-time ultrasound. Sixty-eight (34%) infants had intracranial haemorrhage, 39 (57%) of whom were scanned repeatedly until they were at least 30 days old. Fifteen infants showed some degree of ventricular dilatation. Four had transient dilatation with complete recovery without any form of treatment (group 1), 7 showed persistent but non-progressive dilatation with no treatment (group 2), 3 had rapidly progressive hydrocephalus (group 3), and 1 had cerebral atrophy (group 4). Occipitofrontal head circumference was also followed sequentially from birth and was not abnormal in groups 1 and 2, but abnormal rates of head growth were seen in groups 3 and 4. It is concluded that after intracranial haemorrhage only a small proportion of infants develop frank hydrocephalus, but ventricular dilatation of some degree is common and may require no treatment.     

Gliomas of the tectum and periaqueductal region of the mesencephalon.

Gliomas that arise in the tectal and periaqueductal region of the mesencephalon usually present with hydrocephalus secondary to occlusion of the aqueduct of Sylvius. A review of 486 brain tumors in children treated during a 5-year period revealed 6 children with gliomas of the tectal plate. The 6 children were shunted for hydrocephalus, presumed secondary to aqueductal stenosis, prior to establishing the diagnosis of tectal plate glioma. No abnormalities were noted on the initial, uncontrasted computed tomography (CT) scans. The tumors are isodense without contrast enhancement which makes the CT diagnosis difficult. Magnetic resonance imaging (MRI) is diagnostic and demonstrates the characteristic enlargement of the tectum with increased density on T2 images. T1 density and gadolinium enhancement are variable. Pathological confirmation was obtained by open biopsy in 2 patients, a stereotaxic biopsy was performed on 2 children; 2 children were not biopsied. The tumor histology obtained was that of pilocytic astrocytoma. Two patients were treated with radiation therapy at the time of diagnosis. One child was followed closely and subsequently irradiated after tumor progression. All patients in this series are alive and functioning adequately 2-10 years after the onset of symptoms.     

Endoscopic third ventriculostomy in hydrocephalus associated with achondroplasia

Hydrocephalus in patients with achondroplasia is thought to be due to increased dural sinus venous pressure resulting from narrowing of the jugular foramen. In this setting, where hydrocephalus is presumed to be "vascular" in origin and therefore communicating, endoscopic third ventriculostomy (ETV) would seem contraindicated. The authors describe 3 patients in whom ETV was successfully performed, resulting in MR imaging-documented decreases in ventricle size. The patients were 11 months, 33 months, and 13 years at the time of surgery. All patients had serial preoperative MR images demonstrating progressive hydrocephalus in a "triventricular" pattern with a small fourth ventricle but an open aqueduct. All patients had undergone suboccipital decompression for foramen magnum stenosis prior to the treatment of hydrocephalus. Preoperative retrograde venography revealed variable pressure gradients across the jugular foramen. It is postulated that the increase in intracranial venous pressure resulting from jugular foramen stenosis may lead to disproportionate venous engorgement of the cerebellum and some degree of obstructive hydrocephalus amenable to ETV. The authors discuss the role of suboccipital decompression in the progression of hydrocephalus in patients with achondroplasia.     

Endoscopic third ventriculostomy through the interfornicial space

Endoscopic third ventriculostomy (ETV) is the most common cranial endoscopic surgery being done worldwide for a variety of conditions resulting in hydrocephalus. We report ETV in a case of congenital hydrocephalus with deficient third ventricular roof and wide interfornicial space. A 6-month-old male child presented with gradual progressive head enlargement and signs of raised intracranial pressure. Computed tomography of the head showed aqueductal stenosis with enlargement of third and lateral ventricles. The patient was operated under general anesthesia with endotracheal intubation. A right coronal burr hole and free-hand entry were made into the right lateral ventricle. The anterior part of the septum and the third ventricular roof were deficient with a narrow Monro's foramen and the third ventricular floor was visible through the space between both fornices. ETV was done in standard fashion. Postoperatively the patient showed uneventful recovery clinicoradiologically. We review the literature and discuss the findings and technique of ETV in this rare entity.