Clinical Experience in the Treatment of Idiopathic Normal-pressure Hydrocephalus Using the Programmable Gravity-assisted Valve (ProGAVAesculap):

Management of paediatric hydrocephalous with Miethke fixed pressure gravitational valves. The Alder Hey Children's Hospital experience

OBJECTIVE

The management of paediatric hydrocephalous remains challenging with the complication and revision rates being consistent in the literature. We hypothesise that the use of a fixed pressure gravitational valve for all de novo shunt insertions decreases the rate of functional revisions and that by implementing the routine use of gravitational valves in children, we would see a reduction in over-drainage and slit ventricle syndrome.

METHODS

Retrospective data collection in a single centre, between February 2010 and August 2018. All patients undergoing fixed pressure gravitational Miethke valve insertion were included. We collected data on patients' demographics, reason for shunt insertion, type of valve and time to and reason for first revision. Data analysis was done with SPSS.

RESULTS

A total of 235 patients were included in our study (124 males, 111 females), aged from 0 to 18.6 years (median 0.28). A total of 99 shunt revisions were documented, 30 of which secondary to ventricular catheter malfunction and 28 secondary to infection. The overall mechanical valve survival rates were 88.5%, 86.4% and 85.5% at 1, 2 and 5 years, respectively. Shunt revision due to over-drainage was documented in only 3 cases (1.3%).

CONCLUSION

Our results are in agreement with existing literature regarding shunt failures secondary to all extrinsic factors to the valve (infection and mechanical failure). We have shown that the use of a Miethke fixed pressure valve for all de novo shunt insertions in paediatric hydrocephalus decreases the need for functional revisions with valve survival rates being superior to the ones described for other types.

The Adjustable proGAV Shunt

OBJECTIVE

To evaluate the reliability of the gravitation-assisted adjustable proGAV shunt system with a prospective multicenter study conducted in 10 German hospitals.

METHODS

Enrollment for this observational study began in April 2005 and concluded in February 2006. The protocol required re-examinations 3 and 6 months postoperatively and fixed the endpoint of follow-up at 12 months after implantation. Patients with different types of adult, juvenile, and pediatric hydrocephalus were included and 165 patients were enrolled; 9 died and 12 had incomplete follow-up.

RESULTS

Of the assessable 144 patients, 130 completed the protocol after 12 months, whereas 14 failed because of the need to explant the device, mainly because of infection. In 12 patients, components of the shunt, not the valve, were revised. In 65 of the 144 patients, there were 102 readjustments of the valve in 67 incidences because of underdrainage and in 35 because of overdrainage. In 1 case, readjustment was not possible. Determination of pressure level with the verification instrument was safe and corresponded to the required x-ray controls after adjustments. No unintended readjustments were noted.

CONCLUSION

The proGAV is a safe and reliable device.