Predictors of the need for cerebrospinal fluid diversion in patients with myelomeningocele

Abstract

<jats:sec> <jats:title>Object</jats:title> <jats:p>Many patients with myelomeningocele (MMC) develop hydrocephalus, and most will undergo CSF diversion. The goal of this retrospective study was to determine whether there was a change in the shunt rate over the 7 consecutive years of the study. The authors will also identify the criteria used to determine the need for shunt placement.</jats:p></jats:sec> <jats:sec> <jats:title>Methods</jats:title> <jats:p>During a 7-year period, 73 patients underwent MMC closure at Arkansas Children's Hospital. The shunt rate for each year was calculated. Clinical characteristics were evaluated, including apneic and bradycardic spells, CSF leak, level of the MMC, head circumference, and rate of head growth. In addition, radiological images were reviewed, and the frontooccipital horn ratio (FOHR), ventricular index (VI), and thalamooccipital distance (TOD) were calculated. Comparisons were made between those patients who underwent shunt placement and those who did not.</jats:p></jats:sec> <jats:sec> <jats:title>Results</jats:title> <jats:p>One patient was excluded due to death in the perinatal period. Of the 72 remaining patients, 54 (75%) underwent placement of a ventriculoperitoneal shunt. This rate did not change significantly over time. Between the cohorts with and without a shunt there was no significant difference in age, sex, or race. There was no significant difference in apneic episodes or bradycardic episodes. There was a statistically significant difference in fontanelle characteristics, head circumference at birth, and rate of head growth. Patients who required CSF diversion had a mean head growth of 0.32 cm/day compared with those who did not receive a shunt (0.13 cm/day; p &lt; 0.05). All radiological parameters were found to be statistically significant.</jats:p></jats:sec> <jats:sec> <jats:title>Conclusions</jats:title> <jats:p>In this study, several classic indicators of hydrocephalus in the neonate were not found to be significantly associated with the need for CSF diversion. Fontanelle characteristics, head circumference at birth, and head growth velocity were associated with the need for shunt placement. Imaging information including the VI, TOD, and FOHR are statistically significant measures to evaluate prior to placement of a ventriculoperitoneal shunt. The optimal patient with MMC for CSF diversion will have full to tense fontanelle, increasing head circumference of more than 3 mm/day, and radiological evidence of an elevated VI, TOD, and/or FOHR.</jats:p></jats:sec>

Clinical and ultrasonographic criteria for using ventriculoperitoneal shunts in newborns with myelomeningocele

“…MM, particularly when ruptured, must be considered as a neurosurgical emergency because of the high risk of CNS infections 12 , which is a large public health concern in our state. All children with MM undergo surgical closure of the MM as soon as they are transferred to our hospital to prevent the risk of infection and the risk associated with keeping the placode exposed 11,12,22,27 . Data indicate that the incidence of hydrocephalus and the requirement of VP shunts in these children vary from 52% to 90%; however, some of these data do not provide a clear definition of the optimal timing and criteria for CSF diversion in children with MM 7,9,11,28 .…”

“…All children with MM undergo surgical closure of the MM as soon as they are transferred to our hospital to prevent the risk of infection and the risk associated with keeping the placode exposed 11,12,22,27 . Data indicate that the incidence of hydrocephalus and the requirement of VP shunts in these children vary from 52% to 90%; however, some of these data do not provide a clear definition of the optimal timing and criteria for CSF diversion in children with MM 7,9,11,28 . We verified that 74% children with MM who underwent an institutionalized protocol based on the clinical and TUS criteria required VP shunts, which is the same as the percentage of children who underwent CT scan-based protocols 11 .…”

“…All the children included in this study underwent the same protocol for hydrocephalus in case of MM, as those described in previous reports 9,11,12 . Transcranial ultrasonography (TUS) was chosen as the radiological method for diagnosing hydrocephalus in all neonates, as that described in previous studies 15,16,17 , because of the difficulty in performing CT scan or MRI in these children.…”

“…We consider the measure of HC and evaluation of the fontanels as the most important clinical signs to be observed in these children, according to previously published studies 11,15,16,17,19 . Infant girls with HC of 37.7 cm and infant boys with HC of 38.5 cm who showed an increase in the ventricular system were considered as having hydrocephalus since birth 17,18,20 .…”

“…Hydrocephalus is present in most children with MM 7,9 , thus making it essential to establish criteria for indicating ventriculoperitoneal (VP) shunts in these children 9,10,11,12 . Brazil is a large country with socioeconomic imbalance 13 and poor accessibility to radiological methods of diagnosis, such as computed tomography (CT) or magnetic resonance imaging (MRI), for routine examination of neonates with neurological diseases in public health hospitals, which makes it difficult to apply standardized protocols followed in developed countries 9,11,14 . This study aimed to describe the epidemiological profile of children with MM by considering the records of a public pediatric reference hospital and identify clinical and transcranial ultrasonographic criteria for the indication of VP shunts in these children.…”