Purpose: Incidentally detected asymptomatic Dandy-Walker syndrome (DWS) is sparsely reported in literature at extremes of age (from 1 to 75 years) in association with different diseases. Precipitating factors causing DWS in these cases to manifest in late adulthood are still unidentified. We tried to hypothesize the aetiology and the natural course of disease based on review of literature
Material and methods: Twelve cases of asymptomatic DWS were selected retrospectively in this study while being treated for some unrelated disease over a period of 15 years.
Results: All the cases had vermian hypoplasia with sizeable fourth ventricular cyst (more than 3 cm), large posterior fossa and with no or borderline ventriculomegaly on CT/MRI. The age ranged from 1 to 65 years. Five cases presented with head injury and four cases presented with enlarged head size with suboccipital protuberance (noticed in children more than 5 years). Remaining cases presented with either occipital encephalocele or right trigeminal neuralgia or fixed atlantoaxial dislocation. They were asymptomatic for DWS following treatment of the presenting complaints on follow-up of average duration of 4.5 years.
Conclusion: Presentation at extremes of age signifies that slow degenerative changes in communicating channels between fourth ventricular cyst and surrounding basal cisterns may cause asymptomatic DWS to manifest, but cases having good communication between these structures can remain asymptomatic throughout their life.