Matching midbrain-sonography to its macroanatomic correlate

Introduction: Transcranial sonography (TCS) is a recently established neuroimaging technique that allows visualizing several brainstem structures including the substantia nigra (SN). Using TCS, an echogenic region can be detected at the suspected anatomical location of the SN and this echogenic area amounts to around 0.12cm2 in healthy controls. Although the location of SN-echogenicity is consistent with the location of the anatomical location, it remains unknown which part of SN is displayed because the rostro-caudal level of the 2-dimensional ultrasound plane in relation to the longitudinal axis of the SN has…