Diagnosis of Joubert syndrome via ultrasonography.

Joubert syndrome (JS) and related disorders (JSRD) are a group of multiple congenital anomaly syndromes in which the diagnostic hallmark is the molar tooth sign (MTS), a complex midbrain malformation visible on brain imaging. Detection of the MTS should be followed by a diagnostic protocol to assess multi-organ involvement. The incidence of JSRD ranges between 1/80,000 and 1/100,000 live births, although these values may represent an underestimate.