Page 42 - Inaugural Lecture Prof Dr Ahmad Sobri Muda

Neurointervention

MRI in Acute Stroke

Numerous studies have demonstrated that computed tomography
(CT) is far less sensitive than magnetic resonance imaging (MRI),
especially diffusion-weighted imaging (DWI), for identifying the
infarct core and estimating the volume. The tissue time concept
requires much more information from imaging is even further
supported by recent criticism over the present theory of the ischemic
core. Susceptibility weighted imaging (SWI), and DWI/ADC, has
proven to be more sensitive than CT at detecting blood. Even though
MRI gives hyperacute stroke patients much more useful insights,
it has a number of disadvantages, such as perception of premium
price, prolonged scan time, and lack of availability. Recent findings,
however, indicate that using an MRI-first policy for hyperacute
stroke does not substantially lengthen the door to needle (DTN)
time. Our institution is among the few adopts MRI-first policy
using Putra Acute Stroke Protocol (Figure 13), which comprises
of an initial 8-minute first three sequences of magnetic resonance
angiography (MRA), fluid-attenuated inversion recovery (FLAIR),
and DWI, is only used by a select few institutions, including ours.
(Muda et. al. CVNS 2021).
If DWI reveals probable bleeding, our protocol modifies the
order of the sequences so that susceptibility weighted imaging
(SWI) follows DWI sequence. Imaging is halted after the first
three sequences so that the clinical team can determine whether
to commence intravenous tissue plasminogen activator (IV-tPA)
therapy or initiate preparation to angiography suite for mechanical
thrombectomy (MT). SWI, MRA, and black blood (BB) sequence
with contrast are typically performed in that order during the
scan. ASL (arterial spin labelling), Perfusion MRI and imaging
are obtained if decided for contrast. Our experience adopting
MRI-first policy shows that we can reach a treatment decision at

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