An abnormal appearance of the midbrain in axial magnetic resonance imaging in which the elongated superior cerebellar peduncles give the midbrain an appearance reminiscent of a molar or wisdom tooth. [ https://orcid.org/0000-0002-0736-9199 http://www.ncbi.nlm.nih.gov/pubmed/14657304 ]
Synonyms: Molar tooth sign on imaging Molar tooth sign on brain imaging Molar tooth sign
Term information
- UMLS:C1865060
Molar tooth appearance results from a lack of normal decussation of superior cerebellar peduncular fiber tracts which in turn leads to enlargement of the peduncles, which also follow a more horizontal course. The absence of crossing fibers also leads to a reduction in the anteroposterior diameter of the midbrain and deepening of the interpeduncular cistern.