a-d Molar tooth sign in JBTS. Axial (a), coronal (b) and sagittal (c) T1-weighted images show large, thickened, elongated superior cerebellar peduncles (arrows). Note a deep interpeduncular fossa (white arrowhead) and the vermian cleft (black arrowhead). Midsagittal (d) T1-weighted image shows vermian hypoplasia (white arrowhead). e-f Ectopic posterior pituitary lobe. Postcontrast sagittal and coronal T1-weighted images show a posterior pituitary lobe (arrow) located at the level of the upper infundibulum. A very thin infundibulum is seen (asterisk) (magnified in the right upper corner of E).