AUTHOR=López-Gloria Katerine , Castrejón Isabel , Nieto-González Juan Carlos , Rodríguez-Merlos Pablo , Serrano-Benavente Belén , González Carlos Manuel , Monteagudo Sáez Indalecio , González Teresa , Álvaro-Gracia José María , Molina-Collada Juan TITLE=Ultrasound intima media thickness cut-off values for cranial and extracranial arteries in patients with suspected giant cell arteritis JOURNAL=Frontiers in Medicine VOLUME=Volume 9 - 2022 YEAR=2022 URL=https://www.frontiersin.org/journals/medicine/articles/10.3389/fmed.2022.981804 DOI=10.3389/fmed.2022.981804 ISSN=2296-858X ABSTRACT=Objective: To determine the optimal ultrasound (US) cut-off values for cranial and extracranial arteries intima media thickness (IMT) to discriminate between patients with and without giant cell arteritis (GCA). Methods: Retrospective observational study including patients referred to an US fast-track clinic. All patients underwent bilateral US examination of the cranial and extracranial arteries including the IMT measurement. Clinical confirmation of GCA after 6 months was considered the gold standard for diagnosis. A receiver operating characteristic (ROC) analysis was performed to select the cut-off values on the basis of the best tradeoff values between sensitivity and specificity. Results: A total of 157 patients were included, 47(29.9%) with clinical confirmation of GCA after 6 months. 41(87.2%) of patients with GCA had positive US findings (61.7% had cranial and 44.7% extracranial involvement). The best threshold IMT values were 0.44 mm for the common temporal artery; 0.34 mm for the frontal branch; 0.36 mm for the parietal branch; 1.1 mm for the carotid artery and 1 mm for the subclavian and axillary arteries. The areas under the ROC curves were greater for axillary arteries 0.996 (95% CI 0.991-1), for parietal branch 0.991 (95% CI 0.980-1), for subclavian 0.990 (95% CI 0.979-1), for frontal branch 0.989 (95% CI 0.976-1), for common temporal artery 0.984 (95% CI 0.959-1) and for common carotid arteries 0.977 (95% CI 0.961–0.993). Conclusions: IMT cut-off values have been identified for each artery. These proposed IMT cut-off values may help to improve the diagnostic accuracy of US in clinical practice.