asterion

The asterion is a meeting point between three sutures between bones of the skull. It is an important surgical landmark. Structure In human anatomy, the asterion is a visible (craniometric) point on the exposed skull. It is just posterior to the ear. It is the point where three cranial sutures meet: the lambdoid suture. parietomastoid suture. occipitomastoid suture. It is also the point where three cranial bones meet: the parietal bone. the occipital bone. the mastoid portion of the temporal bone. In the adult, it lies 4 cm behind and 12 mm above the center of the entrance to the ear canal. Its relation to other anatomical structures is fairly variable.