November 30, 2007 --

Conquer Chiari Awards Research Grant To Look For New Chiari Test

Conquer Chiari has awarded a $75,000 research grant to a collaboration of researchers to look for new, objective indicators of symptomatic Chiari.  Published research has shown time and again that the old definition of Chiari, based on the amount of tonsillar herniation below the foramen magnum, is not a good indicator of symptom severity or the need for surgery.

At the UIC/Conquer Chiari Research Symposium 2007, it became clear that there were a number of potential candidates - mostly based on advanced MRI techniques - for a new, objective Chiari test.  The development of such a test is one of the major objectives of the Conquer Chiari Research Agenda, so Conquer Chiari approached a group of researchers after the conference to form a collaboration.  Below is the Abstract as written in the proposal, but the basic ideas is to perform the same group of tests on a group of symptomatic Chiari patients, a group of patients with tonsillar herniation but no Chiari symptoms, and a group of healthy volunteers. In this way, it can be determined if any of the tests correlate to symptomatic Chiari.

The collaboration includes:

• Frank Loth, PhD, BioFluids Lab, University of Illinois-Chicago.

• Bermans Iskandar, MD, Department of Neurosurgery, University of Wisconsin

• John Oshinski, PhD, Associate Professor, Emory University

• Victor Haughton, MD, Professor, Department of Radiology, University of Wisconsin

• Spyros Sgouros, MD, Senior Lecturer, Department of Neurosurgery, University of Birmingham

• Paul Fischer, PhD, Reserach Scientist, MCS Division, Argonne National Laboratory

Proposal Title:
MR Measurement of CSF Wave Speed, Distribution of CSF Velocity and Pressure, Longitudinal
Impedance, and Skull Base Geometry in Chiari Patients

Abstract:
The overall aim of this project is to identify novel methods of analysis that distinguish symptomatic Chiari I
patients who require treatment, from individuals with asymptomatic Chiari I (incidental tonsial ectopia). Four
different engineering methods will be applied on 21 subjects consisting of three groups: 7 volunteers (Group A),
7 asymptomatic Chiari patients (Group B), and 7 symptomatic patients (Group C). The parameters obtained
from the four methods of analysis will be correlated with each group to determine if the parameters are related
to disease severity. Disease severity will be assessed by the presence or absence of a syrinx and neurological
signs and symptoms. Each analysis will utilize subject specific measurements of anatomic geometry and phase
contrast magnetic resonance imaging. The first analysis technique, computational fluid dynamics (CFD), will
compute the cerebrospinal fluid (CSF) pressures and velocities within the subarachnoid space above and below
the foramen magnum. The second technique, longitudinal impedance (LI) calculation, will determine the
unsteady resistance in the subarachnoid space to the flow of CSF at the C2 level. The magnitude of LI is a
measure of the resistance to hydrodynamic resistance due to the reduced cross-sectional area in spinal canal at
the point of herniation. The third technique, pulse wave velocity (PWV), will be used to compute the wave
speed within the subarachnoid space. The magnitude of PWV in the spinal canal is thought to be clinically
relevant as it is an indicator of the compliance within the spinal canal since a higher wave speed indicates a stiff
CSF system as well as elevated magnitude of peak intracranial pressure. Finally, the CSF volume and skull
based geometry will be calculated from the anatomic images. The present study will determine which
parameters are important in accessing the severity of the disease. Parameters examined (geometry, longitudinal
impedance, velocity and pressure distribution, and pulsed wave velocity) will be correlated with a)
symptom severity as defined by a questionnaire designed by the neurosurgeons and b) the presence of
a syrinx. Ultimately, these parameters may provide quantitative clinical information to the neurosurgeon to help
in the diagnosis and treatment of Chiari patients.

Pennsylvania Passes Chiari Awareness Resolution

Pennsylvania has joined Michigan and Ohio in recently passing a Chiari Awareness Resolution.  The resolution was introduced by State Representative Siproth and passed unanimously. 

Many congrats to Nicole Labar who worked to get this done.

Next year, Michigan, Ohio, and Pennsylvania should all be lined up with September as Chiari Awareness Month.

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