Beyond the Molar Tooth: A Review of Imaging Findings in Joubert Syndrome and Related Disorders

Joubert syndrome and related disorders encompass a group of ciliopathies that present with variable neurologic and systemic phenotypes. The diagnosis of Joubert syndrome and related disorders is based on a combination of clinical features and imaging findings, the classic being the “molar tooth sign” that arises from cerebellar hypoplasia. However, multiple additional imaging findings have been reported in the case literature. In this article, we present an overview of the imaging techniques and a review of the imaging findings that the neuroradiologist should be aware of when evaluating a study for a patient with Joubert syndrome and related disorders.

Learning Objective: To discuss the genetics and clinical phenotypes of Joubert syndrome and related disorders and describe the varied neuroimaging findings that can be seen in these patients.