Styloid syndrome: A review of literature

Abstract

The American otolaryngologist Eagle was the first to describe styloid syndrome in 1937. Stylohyoid complex is composed of styloid process, stylohyoid ligament and a lesser horn of the hyoid bone. Embriologicaly, these anatomical structures originate from Reichert's cartilage of the second brachial arch. In the general population, the frequency of the elongated styloid process is estimated to be 4%, of which only 4% show clinical manifestations suggesting that the incidence of styloid syndrome is 0.16% (about 16,000 persons in Serbia). The styloid process deviation causes external or internal carotid impingement and pains which radiate along the arterial trunk. Classical stylohyoid syndrome is found after tonsillectomy and is characterized by pharyngeal, cervical, facial pain and headache. Stylo-carotid syndrome is the consequence of the pericarotid sympathetic fibres irritation and compression on the carotid artery. Clinical manifestations are found most frequently after head turning and neck compression. The diagnostic golden standard for styloid syndrome is 3D CT reconstruction. Sagital CT angiography has a leading role in the radiological diagnosis of the stylo-carotid syndrome. Differential diagnosis requires the differentiation of the styloid syndrome from numerous cranio-facio-cervical painful syndromes. If conservative treatment (analgesics, anticonvulsants, antidepressants, and local infiltration with steroids or anaesthetic agents) has no effect, surgical treatment is applied. Styloid syndrome is underrepresented in neurological literature. The syndrome is considered important, because it is clinically similar to many other painful cranio-facial syndromes; it is difficult to be recognized, and the patient should be treated adequately.