Styloid process-related internal carotid artery dissection: extensive literature review of diagnosis, treatment and outcomes (exemplified with a single-center case series)

PURPOSE: Internal carotid artery dissection (ICA-D) frequently leads to ischemic stroke in individuals under 50 years. There is mounting evidence on the role of the styloid process (SP) in ICA-D, particularly SP length and the SP-ICA distance. Despite having clear guidelines on the treatment of SP-related Eagle syndrome and ICA-D, the concept of SP-related ICA-D is relatively new and no therapeutic guidelines exist. METHODS: A narrative literature search was performed to identify all articles pertaining to the diagnosis and treatment of ICA-D linked to an ipsilateral elongated SP or short SP-ICA distance. The treatments were evaluated in terms of symptom recurrence after the treatment. As illustrative examples of clinical management, we present an in-house case series of patients with suspected ICA-D related to SP. RESULTS: Treatment efficacy was assessed, with an in-house case series provided. Seventy-five reports and case studies involving 84 patients were analyzed. Conservative treatments were common (52%) but had a high symptom recurrence rate (33%). It is noteworthy that no patients treated initially with styloidectomy exhibited symptom recurrence. CONCLUSION: In case of a correctly diagnosed SP-related ICA-D, a styloidectomy may offer a curative option, but more research is needed for clear indications and standardized guidelines to prevent recurrent symptoms or strokes.