Clinical experience with the intraparenchymal intracranial pressure monitoring Codman MicroSensor system.

OBJECTIVE: Our main objective was to study the reliability of the Codman MicroSensor (CMS), used for intracranial pressure (ICP) measurements, as it is used in a clinical setting. In particular, the drift from zero was studied.
METHODS: The investigation is a prospective study of 128 patients with a need for neurointensive care who have been treated for various diseases. The patients received an intraparenchymal CMS device, and the zero drift was measured at explantation of the sensor. In another 22 patients, the ICP was recorded simultaneously from a ventriculostomy and a CMS, and the values were compared. The general data of complications and pitfalls are collected from close to 1000 CMS devices implanted.
RESULTS: The CMS was used, on average, 7.2 +/- 0.4 days per patient. The total time of ICP measurement was 20,040 hours, resulting in at least 7.2 x 10(7) measuring values displayed. The drift from zero was 0.9 +/- 0.2 mm Hg, and no correlation with duration of use was found (P = 0.9, r = 0.002). There was a good correlation between ICP measured by CMS and by ventriculostomy (P < 0.0001, r = 0.79). The average ICP measured with the ventriculostomy was 18.3 +/- 0.3 mm Hg, and with the CMS, it was 19.0 +/- 0.2 mm Hg. A few minor hematomas were identified, and no infections directly connected to the device were observed. Some pitfalls in handling and problems during magnetic resonance imaging investigations are discussed.
CONCLUSION: In our hands, the CMS device is reliable and easy to use. The ICP recordings are stable over time, and there is only a minor zero drift. The device is today our standard method for ICP measurements.