| Popis: |
The purpose of this study was to determine whether the addition of Photodynamic Therapy (PDT) using the photosensitizer Photofrin * (P * ) following balloon angioplasty (BA) could prevent restenosis in an atherosclerotic animal model. Bilateral iliac atherosclerosis was created in 21 Yucatan miniswine. Six weeks later, P * 2.5 mg/kg was given IV 24 hours prior to BA (4 mm X 20 mm, 1 inflation). Following BA, swine were randomly allocated to receive PDT via a fiberoptic probe with laser energy or the same probe without laser energy. The fiberoptic probe had a 1 cm cylindrical diffusing tip and was passed co-axially through a custom catheter to ensure central location of the probe. A continuous wave argon ion-pumped dye laser tuned to 630 nm was used to provide a fluence of 100 J/cm 2 . Four weeks later, swine were sacrificed and vessels perfusion-fixed in-situ with glutaraldehyde and analyzed by ocular micrometry. Five occlusions occurred, all in the PDT + BA group. Percentage intimal thickness (mean +/- SD) was 51.0 +/- 29.5 in the BA group and 71.2 +/- 35.2 in the BA + PDT group (p equals 0.21). These results suggest that the addition of PDT following BA does not prevent restenosis. |
