# Origin of the right vertebral artery from the right common carotid artery in the setting of an aberrant right subclavian artery: Case and retrospective review to determine frequency

## TL;DR

This paper reports a rare case of a right vertebral artery anomaly and finds that in most cases of an aberrant right subclavian artery, the right vertebral artery originates from the subclavian artery.

## Contribution

The study provides new frequency data on the origin of the right vertebral artery in the context of an aberrant right subclavian artery.

## Key findings

- In 84% of patients with an ARSA, the right vertebral artery arises from the right subclavian artery.
- In 16% of patients with an ARSA, the right vertebral artery arises from the right common carotid artery.

## Abstract

Anomalies of the vertebral arteries are rare. The second most common vertebral artery anomaly is the right vertebral artery arising from the right common carotid artery in the setting of an aberrant right subclavian artery (ARSA). We present a case of this rare anomaly and determine the relative frequency with which the right vertebral artery arises from the right subclavian artery vs the right common carotid artery in the setting of an ARSA by retrospectively reviewing over 500 patients with an ARSA and a contrast-enhanced CT. We found that in the setting of an ARSA the right vertebral artery arises from the right subclavian artery in 84% of patients and from the right common carotid artery in 16% of patients.