Chronic vomiting revealing Joubert syndrome: A case report.

Joubert syndrome is a rare autosomal recessive disorder characterized by the presence of the molar tooth sign on imaging. We report the case of a 5-year-old girl diagnosed with Joubert syndrome during the investigation of chronic vomiting. The patient presented with neuropsychomotor delay, a history of neonatal respiratory disorders, and hydrocephalus treated with a ventriculoperitoneal shunt. Brain magnetic resonance imaging revealed a deepened interpeduncular fossa, thickening and horizontalization of the upper cerebellar peduncles, and vermian hypoplasia, resulting in the characteristic "molar tooth" appearance. The neuropsychomotor delay was attributed to Joubert syndrome, while the chronic vomiting was linked to hyperdrainage. This case underscores the potential for clinical signs of Joubert syndrome to confuse clinicians and highlights the importance of recognizing the pathognomonic molar tooth sign in imaging, which all radiologists should be familiar with.