Vascular rings are a rare cause of symptoms in adult patients. We report the case of a 48-year-old woman presenting with dysphagia lusoria due to an uncommon vascular ring: right aortic arch with mirror-image branching and a left ligamentum arteriosum. No previous reports exist of adult-onset dysphagia lusoria attributable to this anatomy. The patient underwent a limited muscle-sparing thoracotomy with division of the ligamentum. The division interrupted the vascular ring and relieved her esophageal compression. The presentation, evaluation, pathophysiology, and treatment of this condition are discussed.