Search

Objectives: The aim of the study was to analyze whether the fixation of the stereotactic frame is stable and whether the location of the treated target coincides with its anatomical location during Gamma Knife surgery (GKS). Materials and methods: Stereotactic MR examinations using the same high-resolution MRI protocol were performed before and after GKS in 18 consecutive patients. The stereotactic (x,y,z) coordinates for three different anatomical landmarks were independently defined three times in each study for each landmark of the images taken before and after GKS by two of the authors, resulting in a total of 648 coordinate definitions. Results: The uncertainty in the readings of the coordinates for the anatomical landmarks was of the same magnitude as the difference in the coordinates before and after GKS in all but one patient. The differences in this one case were due to MR distortion and not to repositioning of the frame. The difference in the coordinates before and after treatment was not affected by the removal of one of the frontal fixation screws in one of the patients. Conclusions: The stereotactic frame position is stable and does not move. [ABSTRACT FROM AUTHOR]

To determine whether intratracheal (IT) lung protective manganese superoxide-plasmid/liposomes (MnSOD-PL) complex provided 'bystander' protection of thoracic tumors, mice with orthotopic Lewis lung carcinoma-bacterial βgalactosidase gene (3LL-LacZ) were studied. There was no significant difference in irradiation survival of 3LL-LacZ cells irradiated, then cocultured with MnSOD-PL-treated compared with control lung cells (D[sub 0] 2.022 and 2.153, respectively), or when irradiation was delivered 24 h after coculture (D[sub 0] 0.934 and 0.907, respectively). Tumor-bearing control mice showed 50% survival at 18 days and 10% survival at 21 days. Mice receiving liposomes with no insert or LacZ-PL complex plus 18 Gy had 50% survival at 22 days, and a 20% and 30% survival at day 50, respectively. Mice receiving MnSOD-PL complex followed by 18 Gy showed prolonged survival of 45% at 50 days after irradiation (P < 0.001). Nested RT-PCR assay for the human MnSOD transgene demonstrated expression at 24 h in normal lung, but not in orthotopic tumors. Decreased irradiation induction of TGF-β1, TGF-β2, TGF-β3, MIF, TNF-α, and IL-1 at 24 h was detected in lungs, but not orthotopic tumors from MnSOD-PL-injected mice (P < 0.001). Thus, pulmonary radioprotective MnSOD-PL therapy does not provide detectable 'bystander' protection to thoracic tumors. [ABSTRACT FROM AUTHOR]