The original point is locatedjust above the intersection point between the cranial 3/4 and the caudal 1/4 ofthe level of the third ventricle, between them a remarkable positive correlationexists and the formula of the linear regression is Y=1.37+0.64Xmm.

• 原点的位置约居第二脑室高的上3/4与下1/4交界处稍上方、两者呈正相关；直线回归方程为Y=1.；37+0