Clinical Trial: Comparison of Continuous Non-Invasive and Invasive Intracranial Pressure Measurement

Study Status: Completed
Recruit Status: Completed
Study Type: Interventional

Official Title: Comparison of Continuous Non-Invasive and Invasive Intracranial Pressure Measurement: Continuous Intracranial Pressure Monitoring Subprotocol

Brief Summary: This research is being done to determine the accuracy of two noninvasive methods of measuring the pressure of the cerebrospinal fluid (CSF), also known as intracranial pressure or ICP.

Detailed Summary:

Recently, astronauts in long-duration spaceflight have been found to have a syndrome consisting of swelling of the optic nerve, impaired vision, and elevated cerebrospinal fluid pressure (also known as intracranial pressure [ICP]) via lumbar puncture (LP), which is similar to the syndrome of idiopathic intracranial hypertension (IIH). In astronauts, this syndrome is called Visual Impairment/Intracranial Pressure (VIIP). It is not possible to perform an LP on astronauts in space. Noninvasive methods of estimating ICP exist but have not been tested against continuous ICP methods in a patient cohort that is physiologically similar to that of astronauts.

The primary objective of this study is to determine the validity, reliability, accuracy, and precision of two noninvasive methods of ICP measurement (tympanic membrane displacement (TMD, Marchbanks Measurements Systems, UK) and distortion product otoacoustic emissions (DPOAE) in comparison to a reference standard, invasive ICP measurement, in human subjects undergoing diagnostic ICP monitoring.

The two noninvasive methods are based on the responses of the inner ear and middle ear to changes in ICP. The first method is TMD, which measures tiny movements of the ear drum, and the second is DPOAE, which is routinely used for newborn hearing screening.

Adults with hydrocephalus or pseudotumor cerebri who have been recommended on the basis of standard clinical criteria to have ICP monitoring either by insertion of a temporary spinal catheter or by insertion of a needle into an existing shunt reservoir are eligible.

After insertion of the spinal catheter or the needle in the shunt, subjects will undergo testing with the TMD and DPOAE in the lying, sitting, standing, and head-down tilt
Sponsor: LifeBridge Health

Current Primary Outcome: Noninvasive ICP [ Time Frame: Day 1 (Concurrent with invasive ICP monitoring) ]

Bland-Altman analysis: the difference between the noninvasive ICP and the invasive ICP is plotted against the mean of both the noninvasive and invasive ICP at each ICP level


Original Primary Outcome: Same as current

Current Secondary Outcome:

Original Secondary Outcome:

Information By: LifeBridge Health

Dates:
Date Received: May 22, 2013
Date Started: September 2014
Date Completion:
Last Updated: October 20, 2015
Last Verified: October 2015