Hollow mandrin facilitates external ventricular drainage placement.
BACKGROUND
Placement of ventricular catheters is a routine procedure in neurosurgery. Ventricle puncture is done using a flexible ventricular catheter stabilised by a solid steel mandrin in order to improve stability during brain penetration. A correct catheter placement is confirmed after removing the solid steel mandrin by observation of cerebrospinal fluid (CSF) flow out of the flexible catheter. Incorrect placement makes further punctures necessary. The newly developed device allows CSF flow observation during the puncture procedure and in addition precise intracranial pressure (ICP) measurement.


METHODS
The developed mandrin is hollow with a blunt tip. On one side 4-5 small holes with a diameter of 0.8 mm are drilled corresponding exactly with the holes in the ventricular catheter, allowing CSF to pass into the hollow mandrin as soon as the ventricle is reached. By connecting a small translucent tube at the distal portion of the hollow mandrin ICP can be measured without loss of CSF. The system has been used in 15 patients with subarachnoid haemorrhage (SAH) or intraventricular haemeorrhage (IVH) and subsequent hydrocephalus.


RESULTS
The new system improved the external ventricular drainage implantation procedure. In all 15 patients catheter placement was correct. ICP measurement was easy to perform immediately at ventricle puncture. In 4 patients at puncture no spontaneous CSF flow was observed, therefore by connecting a syringe and gentle aspiration of CSF correct placement was confirmed in this unexpected low pressure hydrocephalus. Otherwise by using the conventional technique further punctures would have been necessary.


CONCLUSIONS
Advantages of the new technique are less puncture procedures with a lower risk of damage to neural structures and reduced risk of intracranial haemorrhages. Implantation of the ventricular catheter to far into the brain can be monitored and this complication can be overcome. Using the connected pressure monitoring tube an exact measurement of the opening intracranial pressure can be obtained performed without losing CSF.
Heese
O
O
Department of Neurosurgery, University Hospital Hamburg-Eppendorf, Hamburg, Germany. heese@uke.uni-hamburg.de
Regelsberger
J
J
Kehler
U
U
Westphal
M
M
D002408:Catheters, Indwelling; D002543:Cerebral Hemorrhage / Q000150:complications / Q000503:physiopathology / Q000601:surgery; D002552:Cerebral Ventricles / Q000503:physiopathology; D004322:Drainage / Q000295:instrumentation*; D004867:Equipment Design; D006801:Humans; D006849:Hydrocephalus / Q000209:etiology / Q000503:physiopathology / Q000601:surgery*; D007427:Intracranial Pressure / Q000502:physiology*; D008365:Manometry / Q000295:instrumentation*; D011677:Punctures; D013345:Subarachnoid Hemorrhage / Q000150:complications / Q000503:physiopathology / Q000601:surgery; D014696:Ventriculostomy / Q000295:instrumentation*