Fig. 2. Derivation of MRI-guided stereotactic coordinates for cannula implantation in a spontaneously arising brain tumors.
A, Transverse section on a T2-weighted MRI demonstrating a tumor in the left hippocampus. Tumor margins are enclosed by a dashed line. The intersection between the olfactory bulb/frontal lobe border and the midbrain was used as a reference point to determine the coordinates on the Y-axis (a) and the X-axis (b). B, Coronal section on a T2-weighted MRI for calculation of the depth coordinates, i.e. Z-axis (c). In the provided example, values for a, b, and c were 7.6, 3, and 1.3 mm, respectively. C–D, Postmortem MRI showing track of the microdialysis probe in the tumor in the X and Y axes (red arrow), and on the Z-axis (yellow arrow). E, Hematoxylin and eosin staining confirming probe location in the targeted area (yellow dots limit tumor margins, blue dashes limit cannula track, and red dashes limit probe track; lines were drawn with Adobe Photoshop V11.0).