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Artificial Intelligence in Health                                              AI in acute stroke imaging



            were duplicates, conference proceedings, commentaries,   strokes  due  to  atherothrombotic  disease.  Non-invasive
            editorials, or abstracts without full-text access.  imaging techniques used to assess the likelihood of
              A total of 316 studies were initially retrieved through   atherosclerotic plaque formation and evaluate lumen
            database searches. After removing 33 duplicates, 283   diameter reduction include MRI, CT angiograms
            studies remained for title and abstract screening. Of these,   (CTA), and ultrasound imaging. AI enhances imaging
            127 full-text articles were assessed for eligibility based on   interpretation by  identifying  even  minute plaques that
            the inclusion and exclusion criteria. A  final total of 78   may go unnoticed by  radiologists,  thereby  facilitating
            studies were included in the review.               timely diagnosis and treatment of carotid artery disease. It
                                                               also helps standardize the identification and quantification
              The study selection process is depicted in Figure 1.  of carotid plaque across various medical imaging centers
            3. Results                                         and among different physicians. A  study by Kordzadeh
                                                               et al.  demonstrated the applicability and precision of
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            AI has introduced a paradigm shift in medical imaging.  The   AI  in  detecting  carotid  artery  disease  using  grayscale
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            application of AI in stroke imaging spans multiple domains,   static duplex ultrasound images. In their findings, the AI
            including screening, detection, triage, and automated   system achieved 91% sensitivity, 86% specificity, and 92%
            diagnosis of carotid artery disease, 25-27  brain hemorrhage   accuracy in identifying normal carotid arteries, and 87%
            and infarct segmentation, quantification, and prognosis;   sensitivity, 82% specificity, and 90% accuracy in detecting
            distinguishing  ischemic  from  non-ischemic  tissue  and   any degree of carotid artery stenosis. Skandha  et  al.
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            normal versus infarcted brain; 28-36  midline shift detection and   conducted a study using echocolor Doppler  imaging on
            quantification; 37-41  automated ASPECT score calculation; 42-46   the internal carotid arteries of 345 patients and developed
            and detection of dense middle cerebral artery (MCA) and   a  diffusion convolutional neural network to  distinguish
            LVO on CT angiograms. 47-53  Several commercially available   symptomatic and asymptomatic plaques, achieving an
            AI-integrated workflows have been developed to interpret   accuracy of 95.66% (area under the curve [AUC] 0.956,
            ischemic stroke imaging automatically (Table 1). These   p<0.0001). AI algorithms also improve the detection and
            AI-driven tools enhance workflow integration, optimize   characterization of carotid plaques through CTA and MRA.
            radiological interpretation, and improve stroke management.  In CTA, AI enables early plaque detection, standardizes

            3.1. AI in stroke screening                        quantification, and assesses plaque vulnerability. In MRA,
                                                               AI estimates varying degrees of carotid artery stenosis and
            Carotid artery stenosis is commonly associated with   automates risk assessment using MRI-based models, such
            plaque progression and accounts for 10 – 20% of ischemic   as the high-risk plaque MRI model, which automatically
                                                               estimates risk scores related to plaque vulnerability.  These
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                                                               algorithms  play  a  pivotal  role  as  segmentation  systems,
                                                               differentiating between different layers (such as the lumen,
                                                               outer wall, and lipid core), and various components of
                                                               atherosclerotic plaque on T1- and proton density-weighted
                                                               images, enabling precise identification of plaque contours
                                                               and vulnerable lesions.

                                                               3.2. AI in acute stroke imaging
                                                               3.2.1. Assessment of hemorrhage
                                                               Hemorrhagic strokes, classified based on the location
                                                               of  bleeding,  include  subarachnoid  hemorrhage,
                                                               intraparenchymal hemorrhage, and intraventricular
                                                               hemorrhage.  AI algorithms have shown high sensitivity
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                                                               and specificity in detecting hemorrhages, even in
                                                               challenging cases involving small bleeds or complex
                                                               brain anatomy. These tools are capable of segmenting and
                                                               quantifying hemorrhages, thereby improving classification
                                                               and  localization.  For  instance,  a  study  by  Rava  et al.
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                                                               demonstrated that the AI could automate the detection and
            Figure 1. The article search and screening process  triage of patients undergoing non-contrast CT (NCCT)


            Volume 2 Issue 4 (2025)                         3                           doi: 10.36922/AIH025140025
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