Background
Various case series have reported the usefulness of a telemetry reservoir attached to an intraparenchymal probe to record intracranial pressure. This is the first known procedure and subsequent series of use of reservoir transducing intraventricular pressure following neuroendoscopic procedures, including endoscopic third ventriculostomy (ETV), arachnoid cyst fenestration and syringomyelia.
Methods
A total of 6 patients were identified between July 2017 to Feb 2019 (2 male,4 female, ages 30-75) for ETV and reservoir insertion following detection of symptomatic intraventricular Obstructive Hydrocephalus. Following the implantations, pressure readings using telemetry were recorded in sitting, and recumbent positions, with and without valsalva manoeuver post-operatively, at 3 weeks and 3 months alongside clinical assessment and radiology, with follow up range between 2 and 22 months. In addition in three patients, fluid level manometry was also carried out as an additional measurement.
Results
Readings were consistent and reproducible with dynamic manoeuvres, there was correlation between fluid level manometry & telemetry in lying down position, and also correlation between MRI findings and clinical improvement. The pressure waveforms findings which showed clear and immediate change in relation to posture and physiological changes were recorded. The novel use of such a device proved useful as a CSF access port, in addition to ICP monitoring readings. Such measurements can be stored for future comparison in case of clinical change with hydrocephalus and or syringomyelia.
Discussion and Conclusions
Telemetry with an intraventricular catheter is a useful adjunct after CSF diversion neuroendoscopic procedures, to allow monitoring of intracranial pressure, that have so far shown reproducible long-term readings consistent with physiology and clinical & radiological findings.