Crouzon Syndrome and Craniosynostosis - A Review for the Twenty-First Century.

Crouzon syndrome (CS) is a syndromic craniosynostosis most often caused by heterozygous activating variants in fibroblast growth factor receptor 2, leading to premature fusion of cranial sutures and progressive craniofacial dysmorphology. Premature suture fusion alters cranial growth patterns and modifies cranial base anatomy, increasing the risk of raised intracranial pressure, ventriculomegaly or hydrocephalus, and hindbrain crowding; shallow orbits cause ocular proptosis with exposure keratopathy, strabismus and amblyopia; midface (maxillary) hypoplasia results in class III malocclusion and nasopharyngeal narrowing, contributing to sleep-disordered breathing; and middle ear disease and external canal stenosis contribute to conductive or mixed hearing loss. This narrative review aims to highlight clinical features and treatment for patients with CS. This narrative review was formulated by critically evaluating and synthesising a range of existing literature, particularly focusing on review articles published between 2007 and 2026. Diagnosis is based on clinical and radiological assessment, confirmed by molecular testing. Management is staged and multidisciplinary: cranial vault expansion - posterior and/or fronto-orbital - is usually performed in late infancy to protect the brain and vision; midface advancement during later childhood or adolescence addresses ocular exposure, airway obstruction and malocclusion; ongoing ophthalmological, audiological, orthodontic and sleep-medicine management aims to reduce functional impairment. A rarer variant, CS with acanthosis nigricans, results from pathogenic variants in fibroblast growth factor receptor 3 and is characterised by distinctive skin findings and a higher risk of choanal anomalies. With timely diagnosis, structured surveillance and coordinated reconstruction within specialist craniofacial centres, long-term functional outcomes and life expectancy are generally positive.