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Stroke is
the third leading cause of death in Western countries.
Prediction
of the potential growth of a cerebral infarct during the
first hours of
ischemic stroke (AIC) is a crucial issue to reduce mortality and limit
consequences as invalidity and neuro psychological disorders..
Around the irreversible
lesions, ischemia is more
moderate and leads to synaptic dysfunction leading to electrical
silence, this
anomaly has been called "ischemic penumbra", since it is reversible
if ischemia is quickly reduced . Otherwise, the penumbra may evolve
into
infarction, according to ischemia severity.
The
existing MRI techniques are relatively complex to implement and require
contrast intravenous injection. This is no longer usefull with NeurInfarct
based only on conventional MRI sequences. NeurInfarct
is based on
image processing of apparent diffusion coefficient (ADC) maps directly
derived
from the initial sequence of diffusion (DWI). These images measure the
mobility
of water molecules which is reduced in
the fixed area of infarction, but is also slightly disturbed in the
penumbra.
These recent changes are too thin to appear on these images. NeurInfarct will
quantify these changes automatically in order to simulate the real
growth of
the brain infarction.
The principle is to define the
brain infarct core which
appears as a high white signal (red zone) on the right image
(diffusion-weighted image, DWI). The ischemic heart is characterized by
a
significant decrease of ADC (left image). On this map is reported the
previously defined area which will serve as a seed base for the
prediction of
growth potential (yellow circled area).
The
results of the clinical study conducted on 98 patients, jointly with
the stroke
center of “la
Pitié-Salpêtrière” in Paris are published in Radiology 2009 by Rosso et al, . These
results indicate that the performance obtained by NeurInfarct are at least as
good as those of existing MRI techniques require the injection of
intravenous
contrast. Moreover, the results are standardized because the
method is almost entirely automatic, which is an advantage in the
stroke clinical
context.

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