＊耳介前点の場所

brainstormのページより

neuroimage.usc.edu/brainstorm/CoordinateSystems

Pre-auricular points (LPA, RPA)

The proper definition of the preauricular point is: "a point of the posterior root of the zygomatic arch lying immediately in front of the upper end of the tragus". The problem with this definition is that it can be really difficult to localize precisely on the MRI. It can lead to severe misregistration between MRI and MEG/EEG.

Our proposition is to use instead the junction between the tragus and the helix, marked with a red dot in the following figure. It can be located much more precisely both anatomically and on the MRI slices.