Abstract: A medical guide (1, 15) is provided for guiding a medical instrument into a target site within a patient's body, for use in connection with a cross-sectional imaging technique such as magnetic resonance imaging or computed tomography. The medical guide comprises a base (2, 16) adapted to be positioned on the patient's body, a trajectory guide (5, 17) movably connected to the base, wherein the trajectory guide is provided with at least one distal marker (7, 22) and at least one proximal marker (8, 23) visible by said cross-sectional imaging technique, and the markers are separated by at least one portion not visible in a chosen cross-sectional imaging technique. Furthermore, the alignment markers are placed so as to optimize the trajectory path and facilitate the procedure of e.g. taking a biopsy sample using the selected cross-sectional imaging technique.