Photodynamic therapy for atherosclerotic stenoses in Yucatan miniswine.
OBJECTIVE
To determine the feasibility of treating atherosclerotic stenoses with photodynamic therapy (PDT).


METHODS
A prospective study with a 4-week follow-up.


METHODS
Twelve Yucatan miniswine, weighing between 25 and 35 kg.


METHODS
Aortoiliac atherosclerosis was created by a combination of balloon endothelial injury and dietary supplementation with 2% cholesterol and 15% lard for 7 weeks. Then the miniswine were given a porphyrin-type photosensitizer (Photofrin), 2.5 mg/kg intravenously, and treated with 630 nm light through an intravascular, cylindrical, diffusing fibreoptic probe, which was coupled to an argon-pumped dye laser to supply 120 J of laser energy.


METHODS
Differences in luminal narrowing before and after PDT.


RESULTS
Seven miniswine had an increase in luminal diameter, but five had no increase. Microscopy demonstrated a broad range of features in treated vessels, including areas with re-endothelialization and regions of platelet and blood cell adherence with absent or abnormal endothelium.


CONCLUSIONS
Although this study demonstrated resolution in stenoses for some miniswine, questions concerning light dosimetry, mechanism of action and long-term effects remain to be determined.
Hsiang
Y N
YN
Department of Surgery, University of British Columbia, Vancouver.
Crespo
M T
MT
Machan
L S
LS
Bower
R D
RD
Todd
M E
ME
D000818:Animals; D001012:Aorta, Abdominal; D001018:Aortic Diseases / Q000188:drug therapy / Q000473:pathology; D001161:Arteriosclerosis / Q000188:drug therapy* / Q000473:pathology; D017323:Dihematoporphyrin Ether / Q000008:administration & dosage; D004195:Disease Models, Animal; D005069:Evaluation Studies as Topic; D005260:Female; D007083:Iliac Artery; D053685:Laser Therapy; D008297:Male; D010778:Photochemotherapy / Q000295:instrumentation / Q000379:methods*; D017319:Photosensitizing Agents / Q000008:administration & dosage; D013552:Swine; D013556:Swine, Miniature
D017319:Photosensitizing Agents; D017323:Dihematoporphyrin Ether