Pain in the head and neck is mediated by afferent fibers in the trigeminal nerve, nervus intermedius, glossopharyngeal and vagus nerves, and the upper cervical roots via the occipital nerves. Irritation of the nerves by compression, distortion, or a lesion in the central pathways may give rise to pain experienced in the innervated area. In some cases there is a structural abnormality demonstrated by imaging which is responsible for nerve irritation, but in many cases there is no apparent cause for the pain. Trigeminal neuralgia (tic douloureux), a common cranial neuralgia, is covered in detail in Chapter 25 and will not be discussed further here. One feature common to these disorders is the quality of the pain: neuralgic pain is typically e...