Biases in large-vessel vasculitis

Dear Sir, I read the paper from Yamaguchi et al. published in the January 2023 edition of Modern Rheumatology with great interest [1]. I thank them for sharing their observations and insights with the world about the differences between those individuals who appear to have extracranial giant cell arteritis (GCA) and those with just cranial arterial disease. I would like to debate the following points with them. The Chapel Hill Consensus Conference effectively defines large vessels as those that are outside an organ [2]. The superficial temporal artery and the maxillary artery are third-generation branches of the aorta and are defined as large vessels with very clear anatomical differentiation of the vessel wall into adventitia, media, and intima. For that reason, it would be inaccurate to name the two groups of their analysis as those involving large vessels and those not involving, since the cranial arteries are also large vessels. I propose the use of anatomically more accurate terms for their groups—cranial verus extracranial OR carotid system versus those with additional aortic and/or subclavian system disease.