An 84-year-old female slumped over in her chair at a senior citizen
center. She was unable to move her right side.
She arrived in the ED twenty minutes after the stroke onset.
She had a “dense” right hemiparesis with no motor
strength of her arm and face. Her speech was slurred but fluent
and she had normal language comprehension.
The “stroke team” was notified and a “stroke
CT” was performed shortly after her arrival: noncontrast
CT (Figure 1), perfusion CT (Figure 2), and CT angiogram.
Perfusion CT (same level as CT slice in upper right
corner of Figure 1).
(A) Time-to-peak. (B) Cerebral blood volume
Recombinant tissue plasminogen activator (rt-PA) was administered
within 30 minutes of her arrival in the ED.
- What does the noncontrast CT show?
- What does the perfusion CT suggest about the potential
benefit of thrombolytic therapy?
Several new CT and MR imaging modalities have been developed
that could potentially improve acute stroke management (Table 1).
The role of these tests include: (1) accurate early identification
of an acute ischemic stroke; (2) distinguishing potentially salvageable
ischemic brain tissue from irreversible ischemia (the ischemic penumbra);
and (3) visualization of the vascular lesion responsible for the
ischemic event. The benefits of these imaging modalities have yet
to be proven in large clinical trials and their use remains experimental.
Table 1 Advanced Imaging in Ischemic Stroke ||Download (.pdf)
Table 1 Advanced Imaging in Ischemic Stroke
|Early diagnosis of stroke||Diffusion-weighted MRI, perfusion CT, CT angiographic source images|
|Distinguish potentially salvageable brain tissue from irreversibly ischemic tissue||Perfusion CT, perfusion-weighted MRI|
|Identify vascular lesion||CT angiography, MR angiography|
Early diagnosis of stroke can be made using diffusion-weighted
MRI, perfusion CT and CT angiographic source images. Distinguishing
potentially salvageable from irreversibly ischemic brain tissue
can be accomplished using perfusion CT or perfusion-weighted MRI
(Figure 2). Vascular lesions are demonstrated using CT angiography
or MR angiography.
These imaging techniques may, in the future, help select patients
for thrombolytic therapy. For example, early imaging confirmation
of stroke would positively identify patients having an acute ischemic ...