Enhancing Ischemic Stroke Diagnosis: Role of MRI in Acute Management

Objectives*
Ischemic stroke remains a significant global health challenge, leading to substantial mortality and disability.
Timely and precise diagnostic imaging is vital, especially in the acute phase, to ensure effective therapeutic
intervention. MRI plays a crucial role, employing both contrast-enhanced and non-contrast approaches to eval-
uate ischemic changes. It is particularly beneficial in cases such as posterior circulation strokes, small infarcts,
or when distinguishing strokes from mimicking conditions.
Materials and Methods
This study assessed the application of MRI techniques, including diffusion-weighted imaging (DWI), perfusion-
weighted imaging (PWI), fluid-attenuated inversion recovery (FLAIR), and advanced methods like arterial spin
labeling (ASL). These methods were evaluated for their effectiveness in identifying ischemic areas, differenti-
ating penumbra from the infarct core, and guiding therapeutic strategies. Several MRI mismatch techniques
are utilized to assess salvageable brain tissue in acute infarction. Key methods include DWI/PWI mismatch to
identify penumbra, DWI/FLAIR mismatch for estimating symptom onset time, and DWI/ASL or DWI/SWI mis-
matches to evaluate perfusion deficits and vascular occlusions, respectively, aiding in treatment decisions.
Results
DWI detects ischemic lesions early, while ADC maps confirm infarcted regions. FLAIR assists in estimating
stroke onset time. The DWI-PWI combination provides detailed core-penumbra differentiation to guide re-
canalization. Contrast-based PWI maps cerebral blood flow, while ASL offers a non-contrast alternative for
perfusion imaging. SWI identifies hemorrhagic changes, and MR-spectroscopy reveals metabolic alterations,
such as increased lactate and reduced N-acetylaspartate, offering prognostic insights.
Conclusions
MRI, using both contrast and non-contrast modalities, is essential in acute ischemic stroke management. It is
especially valuable in complex scenarios, such as posterior circulation involvement or small strokes, and
when ruling out mimics. Comprehensive MRI protocols improve diagnostic precision and inform effective
treatment decisions, enhancing patient outcomes. Techniques such as DWI/PWI, DWI/FLAIR, and DWI/ASL
mismatches provide critical information about tissue viability, perfusion deficits, and timing, enabling
personalized thera-peutic approaches.