BACKGROUND: Incidence of Crouzon syndrome is 1 per 25.000-31.000 newborns. This syndrome is extremely rarely accompanied by optic canal stenosis. OBJECTIVE: To present a patient with Crouzon syndrome and optic canal stenosis, to discuss the management of such patients considering own and literature data. MATERIAL AND METHODS: A 6-year-old boy presented with Crouzon syndrome (verified by molecular genetic research, i.e. FGFR2 gene mutation). The patient underwent 3 surgeries for craniosynostosis and hydrocephalus. Nevertheless, visual acuity progressively decreased despite patent ventriculoperitoneal shunt. Examination revealed severe decrease in visual functions with optic disc congestion under secondary atrophy. MRI data on subarachnoid CSF accumulation over both optic nerves potentially indicated optic canal stenosis. This assumption was confirmed by 3D CT. RESULTS: The patient underwent decompression of both optic canals with subsequent improvement of visual functions. CONCLUSION: Vision decrease following Crouzon syndrome may be due to optic canal stenosis. Decompression may be effective, even in long-term course of disease, and improve visual functions.