Abstract: There is described a computer-implemented method for designing a stent, comprising: providing for display a first image of a 3D model of at least a portion of a body part comprising an aneurysm; receiving a position for each one of a plurality of reference points chosen along the body part; inserting in the first image a visual marker at the position of each reference point, thereby obtaining a second image; providing the second image for display; for each reference point, calculating a respective diameter; calculating at least one length using the positions of the reference points; and outputting the respective diameter and at least one length.