Review of anatomy and physiology of the face in view of pain-generating and pain-mediating mechanisms

Abstract

Abstract This chapter describes the sensory innervation of the face and head, focusing on anatomical substrates of clinical features that characterize cranial neuralgias. It draws attention to the key role of the caudal part of the trigeminal spinal nucleus and additional roles of the hypothalamus, descending modulation, and the parasympathetic system. The chapter provides an overview of neural excitability together with reasoning of how it can lead to various manifestations of cranial neuralgias. High-throughput ‘whole-genome sequencing’ studies demonstrate that rare mutations in genes involved in a wide range of neuronal functions underlie the risk for developing trigeminal neuralgia. Although still at an early stage, this research strongly suggests that most patients have inherited protein-changing mutations in several genes and that functionally different groups of genes are associated with different clinical subtypes distinguished by sex, age of onset, and presence of neurovascular compression.