Purpose: Stroke, the third leading cause of death and disability worldwide, remains a challenge for diagnosis and treatment. Stroke treatment focuses on three strategies – conservative treatment, thrombolytic treatment (IV rt-PA) or an endovascular procedure. Our purpose is to evaluate whether CTA (early and delayed phase imaging) provides information on cerebral damage equivalent to what is detected on CT perfusion (CTP) prior to endovascular treatment.
Materials and Methods: A retrospective review was done of 54 consecutive adult brain CT examinations (early and delayed phase CTA, CT perfusion) performed from January 3, 2015 – April 10, 2016 on patients admitted to the ER with acute stroke. All patients were candidates for thrombolytic treatment (arriving within 4.5 hours of symptom onset) or endovascular procedure (arriving within 6 hours) and NIHSS ≥ 4 or NIHSS 2 with concomitant major neurological deficit. Independent review was performed by a board certified neuro-radiologist and invasive neurologist. The raters blindly reviewed either the CTA images or CTP images of the selected patient at separate times. The ischemic areas were evaluated on axial imaging only according to ASPECT score.
Results:
- The area measurements of the hypodensities (representing oligemia) on CTA early images were found to be non-equivalent to the penumbra areas seen on MTT/CBF images of the CTP.
- The area measurements of the hypodensities (representing oligemia) of the CTA delayed images were found to be equivalent to the core infarct areas seen on CBV images of the CTP.
Conclusions: CTA should not be used independently for referring to endovascular treatment when CTP is available, and delayed CTA images show equivalence with CBV images on CTP.