PT  - JOURNAL ARTICLE
AU  - Arrigoni, F.
AU  - Romaniello, R.
AU  - Peruzzo, D.
AU  - De Luca, A.
AU  - Parazzini, C.
AU  - Valente, E.M.
AU  - Borgatti, R.
AU  - Triulzi, F.
TI  - Anterior Mesencephalic Cap Dysplasia: Novel Brain Stem Malformative Features Associated with Joubert Syndrome
AID  - 10.3174/ajnr.A5360
DP  - 2017 Dec 01
TA  - American Journal of Neuroradiology
PG  - 2385--2390
VI  - 38
IP  - 12
4099  - http://www.ajnr.org/content/38/12/2385.short
4100  - http://www.ajnr.org/content/38/12/2385.full
SO  - Am. J. Neuroradiol.2017 Dec 01; 38
AB  - SUMMARY: In Joubert syndrome, the “molar tooth” sign can be associated with several additional supra- and infratentorial malformations. Here we report on 3 subjects (2 siblings, 8–14 years of age) with Joubert syndrome, showing an abnormal thick bulging of the anterior profile of the mesencephalon causing a complete obliteration of the interpeduncular fossa. DTI revealed that the abnormal tissue consisted of an ectopic white matter tract with a laterolateral transverse orientation. Tractographic reconstructions support the hypothesis of impaired axonal guidance mechanisms responsible for the malformation. The 2 siblings were compound heterozygous for 2 missense variants in the TMEM67 gene, while no mutations in a panel of 120 ciliary genes were detected in the third patient. The name “anterior mesencephalic cap dysplasia,” referring to the peculiar aspect of the mesencephalon on sagittal MR imaging, is proposed for this new malformative feature.AMCDanterior mesencephalic cap dysplasiaCSTcorticospinal tractIQIntelligence QuotientJSJoubert syndromeSCPsuperior cerebellar peduncle