Browsing by Author "Cox, Pablo"

Now showing 1 - 2 of 2
  • Thumbnail Image
    Publication
    Association of Dual-Phase Computed Tomography Angiography and CTPerfusion in Patients with Acute Ischemic Stroke Beyond the 6-Hour Window
    (2023) Gallardo, Andrés; Lavados, Pablo; Cox, Pablo; De la Barra, Camila; Cavada, Gabriel; Olavarria, Verónica
    Background: There is controversy regarding the need to use advanced imaging to select candidates for thrombectomy in late window acute ischemic stroke (AIS). Hypoattenuation on CT angiography source images (CTA-SI) in arterial phase has been shown to be more sensitive than Alberta Stroke Program Early CT score (ASPECTS) of brain parenchyma to determine tissue at risk of ischemia. Our hypothesis is that the addition of a second acquisition at 35-50 seconds could complement the assessment of hypoperfused tissue that fails to receive flow through pial vessels. Methods: Patients with large vessel occlusion and 6-16 hours from symptom onset, admitted between August 2019 and July 2022 were evaluated with dualphase CT angiography (CTA) and CT-perfusion. The association between automated CT-perfusion valuesand dual-phase CTA was assessed through a correlation coefficient. Results: Pearson's coefficient demonstrated a high correlation between ischemic core volume and delayed CTA-SI with an inverse association of -0.91 and between Tmax≥6 sec volume and arterial CTA-SI with a value of -0.83. Conclusion: CTA-derived source images (CTA-SI) in two phases may be useful in the selection of patients with AIS presenting beyond the 6-hour window.
  • Thumbnail Image
    Publication
    Correlation between dual-phase CTA-SI ASPECTS and automated CT perfusion imaging in patients with acute ischemic stroke beyond the 6-hour window
    (2023) Gallardo, Andrés; Lavados, Pablo; Cox, Pablo; Barra, Camila de la; Cavada, Gabriel; Olavarría, Verónica V.
    Background/Objective: There is controversy regarding the need to use advanced imaging to select candidates for thrombectomy in late window acute ischemic stroke (AIS). Hypoattenuation on CT angiography source images (CTA-SI) in arterial phase has been shown to be more sensitive than Alberta Stroke Program Early CT Score (ASPECTS) of brain parenchyma to determine tissue at risk of ischemia. Our hypothesis is that the addition of a second acquisition at 35-50 seconds could complement the assessment of hypoperfused tissue that fails to receive flow through pial vessels. Methods: Patients with large vessel occlusion and 6-24 hours from symptom onset, admitted between August 2019 and July 2023, were evaluated with dual-phase CT angiography (CTA) and CT-Perfusion. A vascular neurologist estimated CTA-SI ASPECTS in both phases at the time of data entry into the RECCA registry. In contrast, the post-processing of CT-Perfusion images was performed in an automated way through RAPID© software. The association between automated CT-perfusion values and dual-phase CTA-SI ASPECTS was assessed through a correlation coefficient. Results: Pearson’s coefficient demonstrated a high correlation between ischemic core volume and delayed phase CTA (CTA-DP) ASPECTS with an inverse association of −0.93 and between Tmax ≥ 6 sec volume and arterial phase CTA (CTA-AP) ASPECTS with a value of −0.88. Conclusions: CTA-derived source images (CTA-SI) in two phases may be useful in the selection of patients with AIS presenting beyond the 6-hour window.

Implementado por OpenGeek Services