The 'molar tooth sign' in Joubert syndrome.
The molar tooth sign is seen in very few conditions and is a very rare paediatric central nervous system congenital anomaly. Molar tooth sign is the result of cerebellar vermis hypoplasia, thick and maloriented superior cerebellar peduncles, and an abnormally deep interpeduncular fossa. In Joubert syndrome this is seen in about 85% of patients. We present a case of 13 months old baby boy with recurrent episodes of fits and hyperpnoea, regression of milestones and developmental delay. MRI examination showed the characteristic molar tooth sign with apposition of cerebellar hemispheres, batwing-shaped fourth ventricle communicating through a thin fissure with foramen of Magendie, cerebellar vermis agenesis and deep interpeduncular fossa consistent with diagnosis of Joubert syndrome.
Rehman
Imaad ur
Iu
Radiology and Paediatrics Department, The Aga Khan University Hospital, Karachi, Pakistan.
Bett
Zablon
Z
Husen
Yousuf
Y
Akhtar
Ali Syed Muhammad
AS
Khan
Faisal Aziz
FA
D001933:Brain Stem / Q000473:pathology*; D002526:Cerebellar Diseases / Q000473:pathology*; D002531:Cerebellum / Q000473:pathology*; D002658:Developmental Disabilities / Q000473:pathology; D006801:Humans; D007223:Infant; D008279:Magnetic Resonance Imaging; D008297:Male; D013577:Syndrome