Abstract
Objectives
Colour Doppler sonography (CDS) is becoming ever more important in the diagnosis of GCA. Data on cut-off values for intima–media complex thickness (IMT) that can be used in clinical practice to distinguish between normal and inflamed arteries are limited. We aimed to derive potential cut-off values for IMT of seven preselected arteries by comparing IMT between GCA patients and a control group.
Methods
We performed CDS of the preselected temporal, facial, occipital, carotid, vertebral, subclavian and axillary arteries in consecutive newly diagnosed GCA patients between October 2013 and September 2019. A ‘halo’ with positive compression sign was considered a positive finding. We measured the maximum IMT in the preselected arteries and compared it with the maximum IMT of the control group.
Results
We were able to demonstrate a halo sign in at least one of the examined arteries of 244/248 (98.4%) GCA patients. Temporal arteries were the most commonly affected vessels, involved in 192 (77.4%) patients. We found extracranial large vessel involvement in 87 (35.1%) patients. The following cut-off values showed high levels of diagnostic accuracy: ≥0.4 mm for temporal, facial and occipital arteries, ≥0.7 mm for vertebral arteries, and ≥1 mm for carotid, subclavian and axillary arteries.
Conclusion
The involvement of a large array of arteries is easily and commonly detected by CDS and provides a high diagnostic yield in patients with suspected GCA. Proposed IMT cut-off values might further improve the diagnostic utility of CDS in these patients.