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Objective and Importance: Whereas posthemorrhagic hydrocephalus is well known after preterm birth, its association with syringomyelia has been reported only once. Here, we describe two additional patients showing this rare constellation., Clinical Presentation: The children had been born after 27 and 28 completed weeks of gestation, respectively. Both had developed neonatal cerebral hemorrhages. At the age of 4 years, patient 1 presented with progressive ataxia leading to the diagnosis of internal hydrocephalus and extensive syringomyelia. In patient 2, progressive ventriculomegaly and syringomyelia were diagnosed at the age of 4 weeks., Intervention: In both children, ventriculoperitoneal shunting resulted in clinical improvement, decrease of the ventricular size, and regression of the syringomyelia. After surgery, patient 1 developed a subdural hematoma and patient 2 parenchymatous cerebral hemorrhages., Conclusion: The combination of syringomyelia and posthemorrhagic hydrocephalus may be more frequent than commonly assumed. Therefore, neurological deterioration may mandate spinal MRI in addition to cerebral MRI. Syringomyelia seems to result from impaired ventricular cerebrospinal fluid drainage as it regresses after ventriculoperitoneal shunting. Bleeding may complicate the postsurgical relaxation of distended brain parenchyma.

Object: Symptomatic overdrainage in children with shunt-treated hydrocephalus represents one of the more difficult shunt-related diseases and may require repeated surgery. Gravity-assisted valve design has become a standard device to avoid overdrainage in many European pediatric hydrocephalus centers. However, the use of a gravitational valve for relieving symptoms associated with overdrainage has not yet been addressed. The goal of this study was to evaluate the effectiveness of a gravitational valve in the treatment of symptomatic overdrainage in children with shunts., Methods: Seventeen children with an adjustable shunt system and symptomatic overdrainage were treated by insertion of a gravitational valve. Clinical and radiological outcome were monitored for a minimum of 12 months after surgery., Results: Implantation of a gravitational valve resulted in either resolution (n = 12) or improvement (n = 5) of the symptoms. In 1 patient, symptoms remained almost unchanged and the gravitational valve had to be upgraded, resulting in resolution of the symptoms. During follow-up, the pressure setting of the adjustable differential pressure valve had to be changed in 7 patients., Conclusions: The gravitational valve was effective in improving symptomatic overdrainage in the majority of patients in the present study. Because the ideal pressure setting for a given patient is hard to determine a priori, adjustable valve systems appear to be beneficial.

Object: Previous reports suggest that the use of adjustable differential-pressure valves may improve shunt performance. The absence of a flow- or siphon-controlled mechanism, however, is a concern. The goal of this prospective study was to assess the efficacy of valve adjustments in preventing slitlike ventricles in children < 6 months old after the first shunt insertion., Methods: A total of 15 infants < 6 months of age who were undergoing initial shunt placement were included. Imaging was performed preoperatively, at 14 days postoperatively, and every 4 weeks thereafter. Ventricle size was assessed using ultrasonography and MR imaging or cerebral CT scanning at 1 and 2 years postoperatively. Clinical follow-up duration was 24 months for all patients. Valve settings were changed by 50 mm H(2)O if ventricle size decreased by 30% compared to preoperative size., Results: The valve pressure setting was increased to 200 mm H(2)O in 11 children within the follow-up time, whereas ventricle size decreased from 0.6 +/- 0.08 to 0.39 +/- 0.09 (frontal/occipital horn ratio, mean +/- standard deviation). There was neither clinical nor radiological evidence of underdrainage., Conclusions: The adjustable differential-pressure valve used in this study was not effective in preventing slitlike ventricles in the majority of patients. Despite the small number of patients, this study provides a rationale for examining whether new shunt designs (gravitational shunt valves) are superior to conventional shunt systems in managing challenging hydrocephalus problems.

Objects: Cerebrospinal fluid (CSF) leakages through the operation wound following shunt placement are commonly treated by head elevation when the shunt is patent and signs of infection are absent., Methods and Results: In two cases in which the standard therapy of head elevation failed, the leakage was successfully managed by temporary lowering of the opening pressure of the implanted programmable valve. Case 1 was that of a preterm baby with repaired meningomyelocele and shunted hydrocephalus. A shunt infection made shunt removal necessary. Five days after insertion of a new ventriculoperitoneal shunt, transcutaneous CSF flow occurred. The CSF leak was cured by a temporary reduction of the opening pressure from 70 to 30 mm H(2)0. Case 2 was in a 9-month-old child with shunted posthaemorrhagic hydrocephalus. Shunt infection was treated by shunt removal, placement of external ventricular drainage, and antibiotics. CSF leakage through the operation wound developed 24 h after placement of the new ventriculoperitoneal shunt. The CSF leakage was successfully treated by temporarily lowering the opening pressure of the valve from 100 to 50 mm H(2)0., Conclusion: The authors assume that head elevation alone did not generate a sufficient difference between the ventricular and the abdominal pressure for the selected opening pressure of the valve to be exceeded, with the result that CSF flowed around the ventricular catheter and through the operation wound. It is believed that reduction of the opening pressure of the valve led to CSF flow through the shunt and made siphoning possible, resulting in cessation of the transcutaneous CSF flow. The authors propose the prophylactic implantation of a programmable valve in children at high risk of postoperative transcutaneous CSF leakage.

Until this day, the drainage of cerebrospinal fluid, as necessary in case of an acute increased intracranial pressure, is conducted manually by adjusting the hydrostatic height of an external drainage bag. The associated problems with the manual open-loop control strategy are an increasing pressure error over time periods involving no correction and the inherent risk of an overdrainage, which may occur, for example, after changes of the patient’s upper body inclination angle. In this paper, an automatic control strategy is suggested to alleviate these problems thereby increasing the patient’s safety and the overall quality of the therapy. The automatic controller presented in this paper is designed for our newly developed intelligent external ventricular drainage system. The proposed controller has to guarantee robustness and performance in face of uncertain patient intracranial dynamics and nonlinearities associated with the actuator. The controller is thus designed to guarantee robust performance using a mixed uncertainty modeling approach and extended by a self-scheduling approach to compensate for input nonlinearities. Controller performance is validated in nonlinear simulations, an experimental test setup, and animal experiments, involving pigs with an artificially induced hydrocephalus. [ABSTRACT FROM AUTHOR]

Objective: Shunting of the lateral ventricle and the posterior fossa cyst is the advocated surgical therapy for children with Dandy-Walker malformation (DWM) and associated aqueductal obstruction. The high rate of complications of combined shunting stimulated the authors to search for an alternative surgical solution. Clinical Presentation/Intervention: After transtentorial endoscopic ventriculocystostomy, a cystoventricular catheter, connected to a peritoneal shunt, was placed in a neonate with DWM and associated aqueductal obstruction. Immediately prior to ventriculocystostomy, the presence of a blocked third ventricular outflow was reconfirmed by contrast medium injection. Neuronavigation was required to define the surgical path from the lateral ventricle through the tentorium and the overlying small rim of brain parenchyma into the posterior fossa cyst. The postoperative clinical course was uneventful with radiologically proven reduction of the size of the ventricular system and the cyst. Conclusion: Cystoventriculoperitoneal shunt placement after transtentorial endoscopic ventriculostomy is a surgical alternative in very young children with DWM and associated aqueductal obstruction. Copyright © 2005 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]