Injuries of the Cranial Nerves

Cranial nerve injuries range from those causing subtle deficits to injuries causing significant morbidity and mortality. Although these injuries have varied etiologies, this chapter focuses on traumatic and iatrogenic causes, as these are most relevant to surgeons and surgical trainees. Anatomic considerations and mechanisms of injury are discussed for each of the 12 cranial nerves, with particular emphasis on commonly injured segments. Furthermore, this chapter discusses how to focus the history and physical examination to identify the site of injury as well as elucidate the cause of injury. Diagnostic and therapeutic approaches to cranial nerve injuries are reviewed as well, with special focus on evidence-based modalities that have been shown to improve outcomes. Lastly, the chapter discusses the medicolegal aspects of iatrogenic cranial nerve injury, including factors that most commonly result in litigation and payment.