Assessing Photofrin uptake in atherosclerosis with a fluorescent probe: comparison with photography and tissue measurements

• Published in: Lasers in surgery and medicine Vol. 13; no. 3; p. 271
• Main Authors: Hsiang, Y, Stonefield, M, Bower, R D, Fragoso, M, Tsang, V, Crespo, M T, Lundkvist, A
• Format: Journal Article
• Language: English
• Published: United States 1993
• Subjects: Animals; Aortic Diseases - metabolism; Aortic Diseases - pathology; Arteriosclerosis - metabolism; Arteriosclerosis - pathology; Female; Fluorescence; Hematoporphyrin Derivative - administration & dosage; Hematoporphyrin Derivative - analysis; Hematoporphyrin Derivative - pharmacokinetics; Iliac Artery - chemistry; Iliac Artery - metabolism; Iliac Artery - pathology; Injections, Intravenous; Lasers; Male; Microscopy, Fluorescence; Photography - instrumentation; Photography - methods; Spectrometry, Fluorescence; Swine; Swine, Miniature
• ISSN: 0196-8092
• DOI: 10.1002/lsm.1900130303

The purpose of this study was to assess Photofrin porfimer sodium (P*) concentration in atherosclerotic plaque (ASP) using a fluorescence detector (Fluoroprobe) compared with fluorescent photography and chemical extraction of P*. ASP was created in the aortoiliac segments of Yucatan miniswine by a combination of balloon endothelial injury and 2% cholesterol and 15% lard diet for 7 weeks. At that time, swine were given P* I.V. in one of the following single dosages: Group I, 2.5; Group II, 1.0; or Group III, 0.5 mg/kg. Swine were sacrificed 24 hours later and aortoiliac and control carotid artery segments removed. Fluorescence was determined from these segments using photographic techniques, the Fluoroprobe, and a spectrofluorometer after chemical extraction. ASP were identified in all swine using photography and the Fluoroprobe. The intensity of fluorescence measured with the Fluoroprobe for Groups I to III was 1,098 +/- 524, 471 +/- 337, and 295 +/- 173 units, respectively (P < 0.01). The tissue concentration of P* in ASP from each group was 130.4 +/- 82.7, 10.0 +/- 1.2, and 9.1 +/- 0.6 ng/g, respectively (P < 0.01). There was a linear correlation between the fluorescence intensity measured with the Fluoroprobe and the extracted tissue concentration (r = 0.88, P < 0.0001). This study showed that a fluorescent detector such as the Fluoroprobe accurately detects the uptake of P* into atherosclerotic plaque.