Successfully reported this slideshow.
We use your LinkedIn profile and activity data to personalize ads and to show you more relevant ads. You can change your ad preferences anytime.

Imi beta-probe-vp-sound


Published on

SHAPE Society

Published in: Health & Medicine
  • Be the first to comment

  • Be the first to like this

Imi beta-probe-vp-sound

  1. 1. Intravascular Characterization of Atheroscleotic Lesions with 18 F-FDG & A Novel Intravascular Beta Probe A. Tawakol*, D. Elmaleh*, H. Gewirtz*, J. Muller*, A. J. Fischman*, & F. Daghighian† *Harvard Medical School and *Massachusetts General Hospital, Boston, MA † IntraMedical Imaging Inc., Los Angeles, CA.
  2. 2. • An intravascular method is needed to detect vulnerable plaques (VP). • VP contain abundant inflammatory cells, which in turn accumulate 18 F- Fluorodeoxyglucose (FDG). Introduction:
  3. 3. Objective: To test the hypothesis that a catheter- mounted scintillation detector can detect experimental atherosclerotic lesions after injection of FDG.
  4. 4. Methods: • Atherosclerotic Animal Model: – New Zealand rabbits – Balloon injury of the infradiaphragmatic aorta – High cholesterol diet for 10 weeks. • At 10 weeks, 1 mCi/kg FDG was administered to atherosclerotic and control rabbits. • 3-4 hours after FDG, rabbits were sacrificed, and aortas removed as a single segment.
  5. 5. Intra-Vascular Beta Probe • More sensitive to positron emissions than γ rays • A 1 mm diameter, 2 mm-long plastic scintillator was optically coupled to a PMT via a 40 cm long fiber. • Over-all diameter of probe is 1.6 mm. IntraMedical Imaging Inc. LA, CA
  6. 6. Measurement in Animals: • The flexible beta probe was inserted into the abdomino-thoracic aortae. • Measurements made : – At sites of grossly visible plaque, – At non-injured sites in the cholesterol fed rabbits, – In corresponding areas in control aorta, – Each, in triplicate, (at 2 sec/measurement), • The queried aortic segments were then excised and examined using standard well counting.
  7. 7. Results: • Sensitivity of the probe was 850±11 cps/microCi • Catheter-determined activity correlated with well counting measurements:
  8. 8. Results: Beta Probe Counts Plaque Non-plaque 5 10 BetaProbeCounts(cps) n=9 n=15 (P<0.001) 15
  9. 9. Conclusions: • Atherosclerotic plaques can be readily distinguished from non-injured regions by the beta probe. • This newly developed intravascular detector, together with FDG, has promise for the in vivo detection of vulnerable plaques
  10. 10. Discussion • Thinner, more sensitive beta probes are being developed at IntraMedical. • Combination of detection and therapy may enhance the clinical applicability of this technique.
  11. 11. Contacts Ahmed Tawakol, M.D. Mass. General Hospital, Boston, MA Farhad Daghighian, PhD IntraMedical Imaging Inc. LA, CA