Bauer, C.J.* ; Chrysidis, S.* ; Dejaco, C.* ; Koster, M.J.* ; Kohler, M.J.* ; Monti, S.M.* ; Schmidt, W.A.* ; Mukhtyar, C.B.* ; Karakostas, P.* ; Milchert, M.* ; Ponte, C.* ; Duftner, C.* ; de Miguel, E.* ; Hocevar, A.* ; Iagnocco, A.* ; Terslev, L.* ; Døhn, U.M.* ; Nielsen, B.D.* ; Juche, A.* ; Seitz, L.* ; Keller, K.K.* ; Karalilova, R.* ; Daikeler, T.* ; Mackie, S.L.* ; Torralba, K.* ; van der Geest, K.S.M.* ; Boumans, D.* ; Bosch, P.* ; Tomelleri, A.* ; Aschwanden, M.* ; Kermani, T.A.* ; Diamantopoulos, A.* ; Fredberg, U.* ; Inanc, N.* ; Petzinna, S.M.* ; Albarqouni, S. ; Behning, C.* ; Schäfer, V.S.*
     
    
        
Exploring the limit of image resolution for human expert classification of vascular ultrasound images in giant cell arteritis and healthy subjects: The GCA-US-AI project.
    
    
        
    
    
        
        Ann. Rheum. Dis. 84:10 (2025)
    
    
    
      
      
	
	    OBJECTIVES: Prompt diagnosis of giant cell arteritis (GCA) with ultrasound is crucial for preventing severe ocular and other complications, yet expertise in ultrasound performance is scarce. The development of an artificial intelligence (AI)-based assistant that facilitates ultrasound image classification and helps to diagnose GCA early promises to close the existing gap. In the projection of the planned AI, this study investigates the minimum image resolution required for human experts to reliably classify ultrasound images of arteries commonly affected by GCA for the presence or absence of GCA. METHODS: Thirty-one international experts in GCA ultrasonography participated in a web-based exercise. They were asked to classify 10 ultrasound images for each of 5 vascular segments as GCA, normal, or not able to classify. The following segments were assessed: (1) superficial common temporal artery, (2) its frontal and (3) parietal branches (all in transverse view), (4) axillary artery in transverse view, and 5) axillary artery in longitudinal view. Identical images were shown at different resolutions, namely 32 × 32, 64 × 64, 128 × 128, 224 × 224, and 512 × 512 pixels, thereby resulting in a total of 250 images to be classified by every study participant. RESULTS: Classification performance improved with increasing resolution up to a threshold, plateauing at 224 × 224 pixels. At 224 × 224 pixels, the overall classification sensitivity was 0.767 (95% CI, 0.737-0.796), and specificity was 0.862 (95% CI, 0.831-0.888). CONCLUSIONS: A resolution of 224 × 224 pixels ensures reliable human expert classification and aligns with the input requirements of many common AI-based architectures. Thus, the results of this study substantially guide projected AI development.
	
	
	    
	
       
      
	
	    
		Impact Factor
		Scopus SNIP
		Web of Science
Times Cited
		Scopus
Cited By
		Altmetric
		
	     
	    
	 
       
      
     
    
        Publication type
        Article: Journal article
    
 
    
        Document type
        Scientific Article
    
 
    
        Thesis type
        
    
 
    
        Editors
        
    
    
        Keywords
        Denmark; Diagnosis; Cancer
    
 
    
        Keywords plus
        
    
 
    
    
        Language
        english
    
 
    
        Publication Year
        2025
    
 
    
        Prepublished in Year
        0
    
 
    
        HGF-reported in Year
        2025
    
 
    
    
        ISSN (print) / ISBN
        0003-4967
    
 
    
        e-ISSN
        1468-2060
    
 
    
        ISBN
        
    
    
        Book Volume Title
        
    
 
    
        Conference Title
        
    
 
	
        Conference Date
        
    
     
	
        Conference Location
        
    
 
	
        Proceedings Title
        
    
 
     
	
    
        Quellenangaben
        
	    Volume: 84,  
	    Issue: 9,  
	    Pages: ,  
	    Article Number: 10 
	    Supplement: ,  
	
    
 
    
        
            Series
            
        
 
        
            Publisher
            BMJ Publishing Group
        
 
        
            Publishing Place
            Radarweg 29, 1043 Nx Amsterdam, Netherlands
        
 
	
        
            Day of Oral Examination
            0000-00-00
        
 
        
            Advisor
            
        
 
        
            Referee
            
        
 
        
            Examiner
            
        
 
        
            Topic
            
        
 
	
        
            University
            
        
 
        
            University place
            
        
 
        
            Faculty
            
        
 
    
        
            Publication date
            0000-00-00
        
 
         
        
            Application date
            0000-00-00
        
 
        
            Patent owner
            
        
 
        
            Further owners
            
        
 
        
            Application country
            
        
 
        
            Patent priority
            
        
 
    
        Reviewing status
        Peer reviewed
    
 
     
    
        POF-Topic(s)
        30205 - Bioengineering and Digital Health
    
 
    
        Research field(s)
        Enabling and Novel Technologies
    
 
    
        PSP Element(s)
        G-530005-001
    
 
    
        Grants
        NIHR Leeds Biomedical Research Centre
    
 
    
        Copyright
        
    
 	
    
    
    
    
    
        Erfassungsdatum
        2025-07-08