Article
HAKIM programmable valve – reasons for failure to program
Programmierbare Hakim-Ventile – warum lassen sich manche nicht verstellen?
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Authors
Published: | May 4, 2005 |
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Outline
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Objective
Sometimes it is useful to change the pressure of a valve in patients with hydrocephalus even months after implantation. Reasons may be an other mobility or a different pressure situation in the peritoneal cavity. But sometimes it was not possible to change the pressure in the programmable valves.
Methods
From 2000 to 2004 we implanted 262 Hakim programmable valves. In these years we had the situation 6 times that programming after implantation failed after normal repeated programming. We evaluate these cases.
Results
Three of them were programmed after the transmitter was placed upside down. The three remaining valves could not be programmed by any method, even with a MRI-sequence. These were explanted because of these problems. Scanning electron microscopy was used to visualize the structures of the valves. All explanted valves had extensive deposits. Of the three patients whose valves were explanted, all three had reasons for increased protein in the CSF: an extreme premature infant with intraventricular haematoma, an old man with dialysis and consecutive amyloidosis and a young woman after subarachnoid hemorrhage.
Conclusions
The situation that programming of a HAKIM programmable valve fails is rare. In some cases the valve could be repaired by some tricks while the remaining valves were explanted for other problems. All patients with explanted valves had a reason for an increased protein level in the CSF.