Abstract

Background: The styloid process is a slender bony projection of the temporal bone that varies considerably in length, morphology, and calcification. When it becomes abnormally elongated, it can produce a symptomatic condition broadly known as Eagle syndrome, with craniofacial pain, dysphagia, and, less often, neurovascular compromise. Objective: To review the anatomical variations of the styloid process reported in the peer-reviewed literature and to relate these to symptomatology, diagnostic imaging, and management. Methods: A PubMed database search using the Boolean string: (“elongated styloid process” OR “styloid process elongation” OR “elongated styloid” OR “Eagle syndrome”) AND (“anatomical variation” OR “morphological variation” OR “styloid length” OR “styloid morphology” OR “calcified stylohyoid ligament”) AND (“clinical relevance” OR “clinical significance” OR “clinical symptoms” OR “dysphagia” OR “neuralgia”) filtered automatically by date, free full text, English language, and human studies, then screened and synthesised narratively. Risk of bias was appraised using the Joanna Briggs Institute checklists for case reports/ series and the Newcastle–Ottawa criteria for cross-sectional and retrospective studies. Results: Of 93 records identified, 14 studies met the eligibility criteria. Reported normal styloid length ranged from roughly 20–32 mm, with elongation thresholds of 30 mm most often applied and individual elongated processes measuring up to 75–80 mm. Morphological variants like continuous, segmented, and pseudo-articulated were most often classified using the Langlais system. Clinical presentations clustered into three overlapping phenotypes: classic oropharyngeal/cervicofacial pain with dysphagia; stylocarotid/neurovascular compression (transient ischaemic attack, stroke, carotid dissection, aneurysm); and styloidogenic jugular compression (headache, intracranial venous hypertension). Three-dimensional CT was the diagnostic reference standard throughout. Surgical styloidectomy achieved remission of symptoms. Conclusions: Elongation and morphological variation of the styloid process are anatomically diverse but clinically important, producing a recognisable yet frequently under-diagnosed spectrum of craniofacial, pharyngeal, and neurovascular symptoms. Standardised measurement and greater clinical awareness are needed to reduce diagnostic delay; surgical shortening remains the most reliably effective treatment for symptomatic cases.

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