Adjustments in gravitational valves for the treatment of childhood hydrocephalus-a retrospective survey

Objective Debatable disadvantages of preset differential pressure valves in treating pediatric hydrocephalus are the inability to treat over- and underdrainage after implantation without further surgery. This survey aims to retrospectively determine whether adjustments were performed and effectively used for the individual adaptation of CSF drainage from the shunted patients' and families' perspective. In a series of 132 consecutive patients (59girls; 73boys, 0-29 years), families, caretakers, or the patients themselves were interviewed about their experiences after using the proGAV (Miethke-Aesculap, Germany) within a CSF-diverting shunt system. Thereby, the necessity and amounts of adjustments were evaluated. The subjective experiences of the adjustment process as well as the subsequent surgical interventions were documented with a follow-up period of 25.6 +/- 9 months. In 87.9 % of the cases, clinical symptoms improved subjectively after valve implantation. A total of 103 adjustments in 69 patients were performed. In 30 % of patients, more than one readjustment was done. As subjective experience, the adjustment process was described by 85 % of patients as painless or merely uncomfortable. Symptoms improved in 91 % in connection to a new pressure setting. During the entire follow-up period, 61 % of all patients remained free of surgery. The recently used adjustable valves provide good clinical results and seem to lead to satisfactory treatment from the perspective of the affected patients or caretakers. Although a mechanical manipulation of the skin is necessary, the mechanism of the integrated adjustment unit was mostly well tolerated and allows for a noninvasive and MRI stable treatment of over- and underdrainage.