Isolated vagus nerve paralysis associated with internal carotid artery dissection

A narrative review on cervical artery dissection-related cranial nerve palsies

Introduction

This study aimed to emphasize the importance of cranial nerve (CN) palsies in spontaneous cervical artery dissection (sCeAD).

Methods

A search term-based literature review was conducted on "cervical artery dissection" and "cranial nerve palsy." English and German articles published until October 2023 were considered.

Results

Cranial nerve (CN) palsy in sCeAD is evident in approximately 10% of cases. In the literature, isolated palsies of CN II, III, VII, IX, X, and XII have been reported, while CN XI palsy only occurs in combination with other lower cranial nerve palsies. Dissection type and mural hematoma localization are specific to affected CN as CN palsies of II or III are solely evident in those with steno-occlusive vessel pathologies located at more proximal segments of ICA, while those with CN palsies of IX, X, XI, and XII occur in expansive sCeAD at more distal segments. This dichotomization emphasizes the hypothesis of a different pathomechanism in CN palsy associated with sCeAD, one being hypoperfusion or microembolism (CN II, III, and VII) and the other being a local mass effect on surrounding tissue (CN IX, X, XI, and XII). Clinically, the distinction between peripheral palsies and those caused by brainstem infarction is difficult. This differentiation is key, as, according to the reviewed cases, peripheral cranial nerve palsies in sCeAD patients mostly resolve completely over time, while those due to brainstem stroke do not, making cerebrovascular imaging appraisal essential.

Discussion

It is important to consider dissections as a potential cause of peripheral CN palsies and to be aware of the appropriate diagnostic pathways. This awareness can help clinicians make an early diagnosis, offering the opportunity for primary stroke prevention.

Vocal Cord Paralysis as the First Sign of Spontaneous Carotid Dissection in a Patient With Extracranial Internal Carotid Artery Aneurysm

INTRODUCTION

Spontaneous dissection of supra-aortic arteries is an exceptionally rare cause of vocal cord dysfunction. We are reporting a case of spontaneous carotid dissection and internal carotid artery aneurysm presenting as vocal cord paralysis.

CASE REPORT

A 44-year-old female was admitted with hoarseness and swallowing disorders. Diagnostic imaging revealed dissection and obliteration of the right internal carotid artery (ICA) 23 mm from the carotid bifurcation. Electromyography revealed unilateral paralysis/paresis of the right vocal cord. Genetic analyses for thrombophilia, methylenetetrahydrofolate reductase, and plasminogen activator inhibitor 1 were found to be at high risk. The patient was discharged after 5 days without any neurological findings, and control angiography revealed complete restitution of the flow in the right ICA one month later. However, a fusiform aneurysm of the distal part of the extracranial right ICA was detected and excluded with endovascular procedure.

CONCLUSION

Connective tissue systemic disorders and even mild trauma could initiate the dissection process of neck arteries. Precise diagnosis might be difficult even for an experienced neurologist, however, the final outcome is favorable.