Management of intrauterine hydrocephalus

Congenital hydrocephalus in the northeast of Brazil: epidemiological aspects, prenatal diagnosis, and treatment

PURPOSE

Congenital hydrocephalus (CH) has higher proportions in developing countries such as Brazil, reaching rates of 3.16:1,000 newborns. Early diagnosis is essential and can be done during the second trimester of pregnancy, highlighting the importance of regular prenatal care. Our objective is to describe the epidemiological profile of children with CH in the state of Bahia.

METHODS

Consecutive medical records of patients with CH, aged less than 2 years and operated at a pediatric reference hospital between September 2009 and September 2012, were reviewed.

RESULTS

One hundred twenty-one children underwent ventricular peritoneal shunt (VP shunt) due to CH. As for prenatal care, 38% of pregnant women did it regularly. Males predominated with 56% of cases with a median age of 3 months, and 68% were from the countryside area. The most frequent clinical manifestations were bulging fontanelle (37%) and increased head circumference (30%). There were 13 (11%) reports of complications associated with VP shunts. There were nine deaths (7%), and respiratory complications were the main cause.

CONCLUSIONS

Public health measures are the key to increase mothers' knowledge about the importance of regular prenatal monitoring. There was a predominance of male children, with a median age of 3 months, with the majority coming from the countryside.

Fetal hydrocephalus and intrauterine cerebral ventriculoscopy: an animal model

OBJECTIVE

The aim of this study was to create an animal model of obstructive ventriculomegaly in the fetal lamb at 78 days of gestation by injecting maternal blood into the lateral ventricles under ultrasound guidance.

METHODS

An endoscope of 1.2 mm housed in a 1.6-mm trocar was introduced into the dilated lateral ventricle. The lambs were sacrificed after delivery.

RESULTS

All fetuses diagnosed with ventriculomegaly on ultrasound showed dilatation on the anatomical sections. The ventricles had a dilated aspect when compared to the controls. In 1 fetus the septum between the two ventricles was completely ruptured. Microscopically the ependymal cells were flattened and the cellular lining was disruptured.

CONCLUSION

The model proved suitable for ventriculoscopic examination at 128 days of gestation. This should allow to elaborate further on therapeutic studies in this controversial area.

Classification of hydrocephalus and outcome of treatment

PURPOSE

Retrospective analysis in cooperative study of hydrocephalus at institutions of members of the Research Committee on Intractable Hydrocephalus sponsored by the Ministry of Health and Welfare of Japan was performed to determine the functional prognosis for all types of hydrocephalus and thus to clarify the outcome.

METHODS

In preparation of this study, we have proposed the definition, clinical classification and diagnostic criteria of hydrocephalus. We have classified non-tumoral hydrocephalus into eight types based on its etiology and the time of onset. To establish the diagnosis in each type of hydrocephalus, we have set up inclusion and exclusion criteria, as well as supplementary criteria which are useful for its diagnosis.

RESULTS

Analysis of the 1450 cases of hydrocephalus of various etiologies stored in the data base obtained from the study for each type of hydrocephalus revealed that following types and conditions were associated with a neurologic deficit: (1) early fetal hydrocephalus, (2) overt neonatal hydrocephalus, (3) hydrocephalus associated with such severe brain malformations as hydranencephaly, holoprosencephaly and lissencephaly, (4) hydrocephalus associated with severe brain damage, (5) hydrocephalus associated with epilepsy, (6) hydrocephalus shunted late after detection, and (7) hydrocephalus complicated by a shunting operation.

CONCLUSION

The postnatal functional outcome was significantly poor in fetal hydrocephalus diagnosed in the early gestation. Childhood onset hydrocephalus showed a poorer outcome than adult hydrocephalus.

Current prognosis in fetal ventriculomegaly

A review of 51 cases referred for evaluation of fetal ventriculomegaly revealed adequate follow-up data in 40 patients. Three of the fetuses were electively aborted and 37 were delivered. There were no cases of death in utero. Of the 37 infants who were delivered, 26 (70%) were treated with shunt placement for neonatal hydrocephalus. The reasons for nontreatment included: inaccurate diagnosis, resolution of hydrocephalus by the time of delivery, neonatal death, and parental wishes. Survival time in the 26 shunt-treated patients ranged from 5 days to 14 years (average 4.25 years); five of these patients died within the first 2 weeks of life. Among the 26 treated patients, satisfactory cognitive ability was found in 10 (38%). Of the seven surviving nontreated infants, satisfactory cognitive ability was demonstrated in six (86%). Children with myelomeningocele displayed cognitive development similar to that in patients without myelomeningocele. The findings suggest that, of patients with in utero diagnosis of ventriculomegaly, approximately one-half survive (4-year average follow-up interval) and 38% of the survivors treated with shunt insertion have normal cognitive development. No subgroup likely to benefit from in utero treatment of ventriculomegaly was identified. Associated central nervous system or systemic malformations were identified in 26 (70%) of the 37 who came to delivery. This community-acquired series, not collected from a high-risk obstetrical-perinatal service, may reflect the general experience of the neurosurgeon consulting in such cases.

Congenital hydrocephalus: a new experimental model with histopathological study

We describe a new experimental model of fetal hydrocephalus in the lamb. 14 sheep were operated on at 100-120 days gestation for the insertion of a catheter into the fetal aqueduct of Sylvius to block cerebrospinal fluid (CSF) flow. After the operation the intracranial pressure (ICP) was measured daily from the distal end of the catheter. The progress of ventricular dilatation was recorded by ultrasound. At ICP 100 mm/H2O the animals were killed for postmortem examination of the fetuses. Neuropathological examination showed massive dilatation of the ventricles. The ependymal cells appeared to be flat and the cellular lining disrupted. Growth of pseudocysts, cellular stratification and proliferation of the paraventricular germinal cells were observed also. With our new experimental model we were able to control the rise in ICP and correlate the evolution of the anatomical damage with the duration of high ICP and with the gestational age at which it began. Our model can also be used at early stages of gestation for reversing the development of hydrocephalus. It might therefore provide information on the suitability of fetal hydrocephalus surgery.

Pathophysiology and postnatal outcome of fetal hydrocephalus

At the National Kagawa Children's or Kobe University Hospital, 24 cases of fetal hydrocephalus were managed between 1982 and 1988. There were 8 simple, 11 dysgenetic, and 5 secondary cases of hydrocephalus, and the fetal age at diagnosis ranged between 24 and 40 weeks of gestation (average 33.4 weeks). All were diagnosed using ultrasonography, with either magnetic resonance imaging or whole-body computed tomography, additionally performed in 10 patients to determine their usefulness in evaluating the morphology. Four patients underwent transabdominal or transvaginal cephalocentesis in the prenatal period and intracranial pressure was measured during the drainage of cerebrospinal fluid in two of these. Postnatal outcome was analyzed for each type of hydrocephalus. The results suggested that in such cases the fetal brain is subjected to extremely high intracranial pressures resulting from a mixture of hydrocephalic pressure and intermittent uterine constriction. Immediately after birth, the biparietal diameter was found to be increased by an average of 7.7 mm and the hydrocephalic state was transformed into the neonatal type characterized by macrocephaly and a relatively low intracranial pressure. Overall mortality was 25% and 16 of the 24 infants underwent the postnatal shunt procedure, largely at the neonatal stage. The follow-up period varied from 4 months to 6 years (average, 25.8 months for nonfatal cases) and the mean intelligence or developmental quotient was 45.2. There were no significant differences in postnatal outcome between the three major types of fetal hydrocephalus. Findings revealed that the length of the gestation period after the diagnosis of hydrocephalus has a significant effect on outcome (P less than 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)

Hydrocephalus--revision of its definition and classification with special reference to "intractable infantile hydrocephalus"

With the advent of computed tomography (CT) scan, much information has been obtained about the pathophysiology of hydrocephalus. It is now clear that hydrocephalus is not a disease entity but rather a syndrome or sign resulting from disturbances in the dynamics of cerebralspinal fluid (CSF) caused by various diseases. Consequently, it has become necessary to revise its definition and classification. In this paper, a contemporary definition and classification of hydrocephalus are presented. Also, a classification of "intractable hydrocephalus"--with its diagnostic criteria--which is a clinically unsolved problem, is attempted, bearing in mind its place in the clinical management and future investigation of the pathophysiology of hydrocephalus.

Prenatal hydrocephalus: outcome and prognosis

The clinical records of 108 infants presenting with hydrocephalus at birth and operated on from 1971 to 1981 were reviewed in order to evaluate the functional results. Premature newborns and spina bifida patients were excluded. Communicated hydrocephalus (39 cases) and aqueductal stenosis (32 cases, excluding 6 X-linked hydrocephalus and 4 toxoplasmoses) were the two main types of hydrocephalus in this series. Eighty-four percent of the infants were operated on before the age of 3 months. The mean follow-up time was 7 years (range 1 to 14 years). The survival rate, calculated by the life table method, was 62% at 10 years. The functional results were evaluated according to intellectual performance, academic level, and psychological status. Of the 75 surviving children, 28% have an I.Q. over 80 and 50% an I.Q. under 60. The mean I.Q. is 54 (range 0 to 130). Of the 52 children who have now reached school age, only 29% have reached a normal academic level. The psychological status is normal or borderline in 46% of the patients. The importance of head enlargement at birth, ventricular size, and the age at the time of surgery are not related to late functional results. The results were best when there were no associated malformations, no shunt infection, when hydrocephalus was due to aqueductal stenosis (excluding X-linked hydrocephalus and toxoplasmosis), or when the first developmental quotient measured at 6 months was over 80.

Medical imaging of fetal ventriculomegaly

Five cases of fetal ventriculomegaly are described in detail. Following ultrasonography, either computerized tomography or magnetic resonance imaging was used in an attempt to clarify the structural pathology of the ventriculomegaly. In two patients, a precise diagnosis was achieved while a probable diagnosis was established in a third patient. The diverse etiology of fetal ventriculomegaly in these five cases demonstrates that ancillary medical imaging may be necessary to achieve diagnostic precision prior to therapeutic intervention.

A retrospective analysis 21 to 35 years after birth of hydrocephalic patients born from 1946 to 1955. An overall description of the material and the criteria used

219 patients diagnosed as having hydrocephalus before the age of 5 years were traced 21 to 35 years after birth. Fifty-four patients had had operations, but those used before the introduction of ventriculo-atrial shunts did not influence the outcome; the series may be considered to represent the natural history of hydrocephalus. Based on available information in the case notes, patients were divided into 2 groups: 1) proven hydrocephalus, and 2) unproven hydrocephalus. Strict criteria were used. Ninety-nine patients (45%) had died. Serious prognostic factors as to survival were early admission, increasing head circumference, downward displacement of the eyes, and seizures. Together with the criteria suggested for proven hydrocephalus, the above factors may act as a guideline to operative treatment. Fifty-seven percent of 116 known survivors were able to work, 9% lived independently but had no working ability, and 34% needed permanent care or supervision. This outcome is similar to that of shunt-operated patients followed for a shorter period. The only parameters indicative of socio-economic independence in adult life were early admission and absence of seizures in childhood.

Intrauterine hydrocephalus and ventriculomegaly: associated anomalies and fetal outcome

Advances in fetal diagnostic techniques have opened many areas to prenatal anatomical scrutiny. Intrauterine hydrocephalus and ventriculomegaly are conditions which are readily diagnosed. Fetal intervention has been undertaken in humans in order to minimize the craniofacial disfigurement and to maximize the growth potential of the brain. To justify such an approach, the significance of all anomalies should be recognized prior to treatment. The authors have reviewed 41 cases of hydrocephalus diagnosed in utero in order to define associated anomalies and patient outcome. 75% of our personal series and 72% of the reviewed literature cases had other anomalies of the central nervous system. Other system malformations, some of which proved fatal, were seen commonly. Prenatal diagnostic techniques did not always reveal these additional problems. The outcome of these pregnancies is not good. Approximately one third of these fetuses have survived to be treated postnatally and to be followed up clinically. Only 7.5% of this series were felt to have attained normal developmental milestones. The remainder of the survivors have various focal and/or global cerebral deficits.

A cranial nail for fetal shunting

A small number of human fetal hydrocephalics have been treated by ventriculoamniotic shunts of silastic tubing. The Colorado device appears to be the one most commonly used. The original experimental device tested on a primate model resembled a hollow shingle nail. This was designed by Michedja and Hodgen, contained a spring valve, measured approximately 32 X 4 mm and was placed by hysterotomy. An attractive feature of this design was its fixation by impaction in the skull, preventing displacement by fetal activity, a reported disadvantage with the silastic devices. To our knowledge, no one has used this nail-like design and tailored it to transuterine percutaneous placement in a human case.

Management of ventriculomegaly in the fetus

We studied 24 human fetuses with cerebral ventriculomegaly by serial obstetric ultrasound to define the natural history of fetal ventricular enlargement and to develop a management strategy. In 10 fetuses, ventriculomegaly was associated with other severe anomalies; nine of these families chose to terminate the pregnancy. In three other severely affected fetuses in whom ventriculomegaly was detected serendipitously late in gestation, routine obstetrical management was performed; none survived. Eleven fetuses had ventriculomegaly without associated severe anomalies. Ventriculomegaly remained stable or of moderate severity throughout gestation in nine, resolved gradually in one, and progressed in one who did not have signs of increased intracranial pressure at birth. All of these fetuses were viable; three patients required shunting in the neonatal period, and two others by 5 months of age. Although obstetric ultrasound usually can detect anomalies associated with fetal ventriculomegaly, three fetuses with isolated ventriculomegaly had midline brain malformations that could not be distinguished in utero from hydrocephalus, even in retrospect. Prenatal diagnosis improves perinatal management by allowing counseling, and selective pregnancy termination, or selection of the timing, mode, and place of delivery to optimize outcome. Most fetuses with ventriculomegaly do not require intervention before birth.