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.

Department of Emergency Medicine Inselspital Bern University Hospital and University of Bern Bern Switzerland

Department of Neurology Inselspital Bern University Hospital University of Bern Bern Switzerland

Department of Neurology Medical School University of Cyprus Nicosia Cyprus

Department of Otorhinolaryngology Head and Neck Surgery Inselspital Bern University Hospital and University of Bern Bern Switzerland

Faculty of Medicine Masaryk University Brno Czech Republic

Institute of Radiology Cantonal Hospital Münsterlingen Münsterlingen Switzerland

University Institute of Diagnostic and Interventional Neuroradiology Inselspital Bern University Hospital and University of Bern Bern Switzerland

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