Lateral positioning technique for the treatment of far-lateral targets with the Leksell gamma knife:: Technical note

OBJECTIVE: To describe a procedure for Leksell gamma knife (LGK) radiosurgery in a lateral position, for treatment of far-lateral intracranial lesions. METHODS: Positioning of the patient in the lateral decubitus position during LGK treatment switches the x and y axis coordinates. This increases the range of the x-axis, from 52 to 148 mm to 40 to 160 mm (i.e., 12 mm in each direction). RESULTS: Conversion of the coordinates of the isocenters is easily performed with simple mathematical algorithms and does not impair the precision of target positioning, at the isocenters during LGK radiosurgery. CONCLUSION: LGK treatment in the lateral decubitus position is a simple. accurate. procedure for the treatment of far-lateral lesions that cannot be reached with nor mal supine positioning.