Internal Carotid Artery Anatomical Variants and Their Association with Increased Thromboembolic Risk in Vascular Eagle Syndrome

Eagle Syndrome (ES), characterized by an elongated styloid process, has a vascular variant that risks cerebrovascular complications due to Internal Carotid Artery (ICA) compression. The role of pre-existing ICA anatomical variations (tortuosity, kinking, looping) in modulating this risk is unclear. This study aimed to explore the relationship between vascular ES, ICA variants, and thromboembolic risk. We conducted an observational retrospective study on 37 confirmed vascular ES patients in Messina, Italy (2019–2024), collecting data on styloid length, ICA variant type, and the CHA2DS2-VASc score. ICA anomalies were highly prevalent (96% of arteries). Crucially, while no correlation was found between styloid length and the CHA2DS2-VASc score, a statistically significant association was detected between the ICA anatomical variant type and the CHA2DS2-VASc score (Fisher’s exact test p = 0.024). This suggests that ICA morphology, rather than styloid length alone, is associated with an elevated thromboembolic risk profile in vascular ES patients, emphasizing the need for detailed CT angiography evaluation to guide personalized management.