Clinics in diagnostic imaging (118)

Subramanian S, Hari S, Santosh Kumar S
Correspondence: Dr Subramanian Subramanian, drsubbusmc@yahoo.co.in

ABSTRACT
An 18-month-old boy presented with delayed milestones, hypotonia, strabismus and an episode of seizure. Magnetic resonance (MR) imaging of the brain revealed abnormally-oriented and thickened superior cerebellar peduncle, giving rise to the characteristic molar tooth sign on axial images. The isthmus was thinned out, with widened interpeduncular cistern and hypoplastic vermis. The clinical and MR imaging features were diagnostic of Joubert syndrome.

Keywords: congenital brain abnormalities, hypoplastic cerebellar vermis, Joubert syndrome, magnetic resonance imaging, molar tooth sign
Singapore Med J 2007; 48(9): 869–873