CASE 9353 Published on 29.07.2011

Eagle\'s syndrome


Head & neck imaging

Case Type

Clinical Cases


Nelson AS, Madani H, Ganguly A, Nixon PP.
Royal Liverpool university hospital


45 years, female

Area of Interest Ear / Nose / Throat, Head and neck ; No Imaging Technique
Clinical History
A 45-year-old lady presented to ENT with a 2-month history of intermittent hoarseness of voice and a lump in the left sub-mandibular region. An ultrasound examination showed an echogenic area in the left sub-mandibular region with posterior acoustic shadow. X-ray revealed a left-sided ossified stylohyoid ligament.
Imaging Findings
Ossified left sided stylohyoid ligament.
Eagle's syndrome was first described by the American otorhinolaryngologist Watt Weems Eagle. He described two distinct syndromes: the classic styloid and carotid artery syndrome. [1, 2] In the classic Eagle syndrome patients are symptomatic with facial/ear/throat pain, dysphagia or tinnitus, thought to be caused by fibrous tissue distorting the cranial nerve endings in the tonsillar fossa. In the carotid artery syndrome the elongated styloid process is in contact with the extra-cranial internal carotid artery. Symptoms are thought to be due to pressure on the sympathetic chain, which accompanies the carotid arteries, causing compression or dissection of the carotid artery resulting in transient ischaemic attack or a stroke.

Diagnosis is guided by history, clinical examination and imaging. There are two possible imaging findings, an elongated styloid process (>30 mm) or ossification of stylohyoid or stylomandibular ligaments [3, 4]. Plain films are diagnostic but the modality of choice is CT with 3-D reconstruction [3]. The role of clinical history cannot be overemphasised since up to 10% of patients may have an elongated styloid process without any symptoms [5]. Also, a recent paper reviewing asymptomatic candidates showed ossification of the stylohyoid ligament in about 25% [6].

A high index of suspicion is however needed in order to identify the vascular form and a styloidectomy is the treatment of choice.

Differential diagnosis of Eagle’s syndrome consists of inflammatory diseases of the pharynx, tumours, dysfunction of temporal-mandibular joint and glossopharyngeal pain [4].
Differential Diagnosis List
Eagle's syndrome
Anatomical variant
Final Diagnosis
Eagle's syndrome
Case information
DOI: 10.1594/EURORAD/CASE.9353
ISSN: 1563-4086