HydrocephalusComparison of programmable shunt valves vs standard valves for communicating hydrocephalus of adults: a retrospective analysis of 407 patients
Introduction
Although the clinical symptoms of some selected patients with communicating hydrocephalus might improve by third ventriculostomy [9], [10], the standard therapy is still cerebral spinal fluid (CSF) diversion by implantation of a shunt system. Since the introduction of the first artificial CSF shunt in 1949 [11], a vast number of different valves have been invented—approximately 130 different types are currently available. At present, standard differential pressure valves with a fixed opening pressure are commonly used in adult patients with communicating hydrocephalus. The fixed opening pressure of the valve requires the surgeon to anticipate the drainage needs of the patient before the implantation of the valve. Furthermore, optimal drainage pressures in an individual patient may vary over time. Therefore, fixed pressure valves are subject to complications of CSF over- and underdrainage, resulting in typical complications: extra-axial fluid collections [nontraumatic subdural hematomas (SDH) or hygromas], slit ventricle syndrome, craniosynostosis in children in cases of overdrainage, or persisting ventriculomegaly with associated clinical symptoms in cases of underdrainage [13].
Therefore, during the late 1980s, Black et al and Hakim [5], [7] developed a variable pressure valve. It allows the percutaneous setting of the opening pressure by a noninvasive magnetic programmer in differential steps of 10 mm H2O from a minimum pressure of 30 mm H2O to a maximum pressure of 200 mm H2O. The option of a percutaneous opening pressure adjustment attempted to reduce the number of surgical shunt revisions for over- or underdrainage. However, a major disadvantage of programmable valves compared with standard valves is the considerably higher cost. Only a significant reduction in the incidence of shunt malfunctions and therefore surgical interventions would justify the additional costs of using a programmable shunt valve. Unfortunately, such an advantage has not been demonstrated by any study so far. To date, no obvious differences in the clinical outcome of patients with programmable and nonprogrammable valves have been reported.
The aim of the present retrospective study was to elucidate whether programmable shunt valves actually reduce the incidence of valve-related surgical shunt revisions in adult patients with communicating hydrocephalus at our institution.
Section snippets
Study methods
This single-center study retrospectively analyzed patients who were shunt implanted for nonocclusive communicating hydrocephalus during January 1990 and December 2001. Departmental databases were used to identify all cases of shunt implantation for hydrocephalus and all cases of shunt revisions during the pertinent period. Patients diagnosed for communicating hydrocephalus (ie, idiopathic normal pressure hydrocephalus, posthemorrhagic, posttraumatic, postinfectious, or other communicating
Results
A total of 407 adult patients diagnosed for communicating hydrocephalus were included in the study. All patients were shunt implanted using either a ventriculoperitoneal (n = 347) or a ventriculoatrial (n = 60) shunt system with a CHP or an H differential pressure shunt valve.
Problems of hydrocephalus shunting
Managing hydrocephalus by implantation of a shunt system is associated with a distressing number of complications, and even with the development of advanced valve systems, shunt-related morbidity remains a common problem. Especially, CSF overdrainage associated with extra-axial fluid collections, such as nontraumatic SDH, hygromas, or slit ventricle syndrome in adults, remains a significant problem [1], [2]. Furthermore, the insufficient drainage of CSF by a shunt (underdrainage) can result in
Conclusion
The advantage of reprogramming of the CHP valves did not translate into an overall reduction in the surgical revision rate compared with that for H valves. With regard to the substantial acquisition costs for CHP valves and the lack of a proven clinical benefit, we believe it is still justifiable to implant H valves in adult patients with communicating hydrocephalus. However, we believe that a minority of patients with communicating hydrocephalus might benefit from programmable shunt valves. To
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Failure of Internal Cerebrospinal Fluid Shunt: A Systematic Review and Meta-Analysis of the Overall Prevalence in Adults
2023, World NeurosurgeryCitation Excerpt :Shunt brand, type, and other features do not influence the failure rate; Anderson et al.7 noted that 3 trials failed to show a significant difference between the valve types, regardless of the price.11,31,36,41,48 The finding was similar for the surgical technique: VPS is apparently not better compared with the ventriculoatrial shunt event if this assertion is debatable.2,9,23,24,31,50 The use of laparoscopy can reduce the risks of distal shunt catheter failure, but it has less effect on overall shunt failure.13,28,29,40,50,51
Shunt valve technology
2022, Cerebrospinal Fluid and Subarachnoid Space: Pathology and Disorders: Volume 2Adjustable pressure valves for chronic hydrocephalus following subarachnoid hemorrhage: Is it worthwhile?
2020, Clinical Neurology and NeurosurgeryCitation Excerpt :APV are more expensive and presumably more prone to malfunction due to their sophisticated mechanical setup [32,33]. This problem has been widely addressed for different diseases causing hydrocephalus [22]. Especially for normal pressure hydrocephalus, it has been shown that advantages might outweigh the disadvantages of this valve type [2,11,25].