Disclosed medical data processing method for planning an external ventricle drainage placement, wherein the method comprises executing, on at least one processor (3) of at least one computer (2), the following steps: a) patient image data describing at least one image of an anatomical structure of a patient is acquired (S1); b) atlas data describing a model of the anatomical structure is acquired (S2); c) mapping data describing a mapping of the patient image data to the atlas data is determined (S3); d) spatial relationship data is acquired (S4) which describes a predetermined spatial relationship between at least one potential trajectory for placing the external ventricle drainage in the anatomical structure on the one hand and a surface of the anatomical structure on the other hand; e) entry point data is determined (S5) which describes the position of an entry point (13) of the external ventricle drainage on the surface of the anatomical structure based on the mapping data and the spatial relationship data.