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Programmable valve breakage in shunt systems of children with posthemorrhagic hydrocephalus after minor head trauma-a
Frank P Schwarm1, Jasmin Nagl1, Michael Bender1
1Department of Neurosurgery, Justus-Liebig-University Giessen, Klinikstrasse 33, 35392, Giessen, Germany.
Insights
Programmable valve breakage is a rare complication in pediatric hydrocephalus shunts. This study highlights five cases of Codman Hakim-Medos valve failure, emphasizing the need for vigilance after minor head trauma.
Area of Science:
- Pediatric Neurosurgery
- Medical Device Complications
- Hydrocephalus Management
Background:
- Posthemorrhagic hydrocephalus in children often requires cerebrospinal fluid shunting.
- Programmable valves, like the Codman Hakim-Medos valve, offer adjustable cerebrospinal fluid (CSF) flow rates.
- Mechanical failure of shunt components is a known, though infrequent, complication.
Observation:
- Five pediatric cases of posthemorrhagic hydrocephalus presented with shunt malfunction between 2013-2018.
- Patients experienced symptoms suggestive of overdrainage or shunt failure following minor head trauma.
- Radiological imaging revealed dislocation of the pressure control chamber within the valve reservoir.
Findings:
- Surgical exploration confirmed mechanical breakage of the Codman Hakim-Medos programmable valve in all five cases.
- The pressure control chamber had dislodged to the bottom of the valve reservoir.
- This specific complication occurred in 4.3% of implanted Codman Hakim-Medos valves during the study period.
Implications:
- Valve breakage, though rare, is a critical complication that can be missed, especially after head trauma.
- Clinicians should consider programmable valve failure in pediatric patients with hydrocephalus presenting with shunt malfunction symptoms.
- Prompt diagnosis and surgical intervention with valve replacement can resolve symptoms and restore effective CSF diversion.
Purpose:
We report five rare cases of programmable valve breakage (Codman Hakim-Medos valve) in shunt systems of children with posthemorrhagic hydrocephalus. Only four similar studies have been published in the current literature.
Methods:
Between 2013 and 2018, five children with posthemorrhagic hydrocephalus were admitted to the pediatric department. All patients had a history of slight blows to the head in a minor trauma and follow up MRI scans. After initial clinical examination, cranial computed tomography (CT) and X-ray were conducted.
Results:
In all cases, pumping the reservoir resulted in very slow refilling. The cranial CT in one patient showed slit ventricles confirming the suspicion of overdrainage, the other cases a slight enhancement of the hydrocephalus. In lateral X-rays of the skull in comparison to the first X-ray control of the shunt valve, the pressure control chamber could be seen dislocated in the inferior part of the reservoir in all cases. Surgery revealed that the shunt valve was broken. The pressure control chamber had dropped to the bottom of the reservoir. After implantation of a new shunt valve, the symptoms resolved completely in all five children. Overall this complication occurred in 4.3% (5 of 85 implanted Codman Hakim-Medos valve) of all children necessitating ventriculoperitoneal shunt implantation between January 2013 and December 2018.
Conclusion:
The well-accepted Codman Hakim-Medos programmable valve is part of a tube-system, which is designed to offer the possibility of a reliable and precise treatment of hydrocephalus. Various mechanical and non-mechanical complications of shunt systems have been reported. Valve breakage is a very rare condition, often missed, and must be kept in mind when trauma and prior MRI scan are reported.
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