20.500.12556/DiRROS-29620 OMERACT GCA phantom project validation of a 3D-printed ultrasound training phantom for diagnosis of giant cell arteritis Objective: Ultrasonography is crucial for diagnosing giant cell arteritis (GCA); however, training opportunities are rare. This study tested the reliability of ultrasonography findings and measurements of the intima-media thickness (IMT) among ultrasonography experts by using phantoms of the axillary (AA) and temporal arteries (TA) created with high-resolution 3D printing. Methods: Twenty-eight participants from 12 European countries received eight sets of phantoms of the AA and the superficial TA (including common, frontal and parietal branches), which were examined in a blinded fashion according to a predefined protocol and evaluated based on Outcome Measures in Rheumatology (OMERACT) GCA ultrasound definitions. Due to difficulties with the delineation of the intima-media complex, the parietal branch of the phantoms was modified, and a second round was conducted. The IMT was measured, and phantoms were classified as normal or vasculitic. Results: In both rounds, the phantoms were correctly classified as normal/abnormal in >81% of cases yielding a Fleiss' kappa of 0.80 (95% CI 0.78 to 0.81) in round 1 and 0.74 (95% CI 0.72 to 0.75) in round 2. IMT measurements revealed an intraclass correlation coefficient (ICC 1.1) of 0.98 (95% CI 0.98 to 0.99) in both rounds. Intrarater reliability was good with a median Cohens Kappa of 0.83 and median ICC of 0.78. Conclusion: The study demonstrated high reliability among ultrasound experts in applying the OMERACT ultrasound definitions for GCA and in measuring the IMT using a 3D-printed phantom of the AA and TA. This phantom could assist clinicians in training to assess the large arteries of patients with suspected or established GCA. giant cell arteritis ultrasonography vasculitis gigantocelični arteritis ultrazvok vaskulitis true false true Angleški jezik Slovenski jezik Neznano 2026-06-01 14:15:53 2026-06-01 14:15:53 2026-06-02 03:48:27 0000-00-00 00:00:00 2025 0 0 Nasl. z nasl. zaslona; Opis vira z dne 8. 5. 2026; str. 1-9 iss. 1, [article no.] e005316 Vol. 11 2025 0000-00-00 Zaloznikova Objavljeno NiDoloceno 0000-00-00 0000-00-00 0000-00-00 616-002 2056-5933 10.1136/rmdopen-2024-005316 277578243 RAZ_Schremmer_Tobias_2025.pdf RAZ_Schremmer_Tobias_2025.pdf 1 C21AD30029E8B7CC7B415437E8B414DB 1ee87e95d9ae0975cc7713cf2e23d87696d79a71000520435061bed99876d8ff e3be80c5-5db3-11f1-8e51-001a4af901a5 https://dirros.openscience.si/Dokument.php?lang=slv&id=44481 https://rmdopen.bmj.com/content/11/1/e005316 1 a731d121-5db3-11f1-8e51-001a4af901a5 https://dirros.openscience.si/Dokument.php?lang=slv&id=44478 Univerzitetni klinični center Ljubljana 0 0 0