Joubert syndrome

Case contributed by Adan Radiology Department
Diagnosis certain


Ataxia and developmental delay.

Patient Data

Age: 6 years
Gender: Female

Non enhanced MRI


Thickened and elongated superior cerebellar peduncles give a ‘molar tooth sign. There is also reduced anteroposterior diameter of the midbrain with deepening of the interpeduncular cistern and hypoplasia of the cerebellar vermis. The rest of the cerebellum and brain stem appear normal.

Both cerebral hemispheres appear normal with preserved grey/white matter differentiation. Normal appearance of the corpus callosum. A normal ventricular system, basal cistern, Sylvian fissures and convexity sulci.


Thickened and elongated superior cerebellar peduncles giving ‘molar tooth signs and hypoplasia of the cerebellar vermis is in keeping with Joubert syndrome.

Case Discussion

Joubert Syndrome is an autosomal recessive disorder with a prevalence of 1 in 100,000. Vermian hypoplasia and molar tooth sign of the midbrain is the disease's neuroimaging hallmarks, although several other associated findings have been reported.

This patient did not have any family members with a similar condition and no related disorder was identified.

 Case courtesy Dr Aneeta Susan.

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