Photodynamic Therapy for Esophageal Varices using δ-Aminolevulinic acid

点击翻译按钮获取中文摘要

Objectives : To observe the hemodynamics and histological changes of the rabbit auricles following PDT and to evaluate feasibility that PDT could be a useful adjunct to other methods for esophageal varices treatment. Methods : Photofrin (photosensitizer) and an argon-dye laser (630 nm, 300 mW/cm2) were used. Twenty rabbits were classified according to Photofrin dose : group I (2.0 mg/Kg, n : 10) ; group II (1.0 mg/Kg, n : 6) ; group III (0.2 mg/Kg, n : 4). Rabbit auricular veins were classfied according to laser illumination time : V0, no illumination ; V5, 5 min. ; V10, 10 min. ; V15, 15 min. The hemodynamics were observed with a laser Doppler blood flowmeter. The histological features of the auricles following PDT were evaluated by light microscopy. Results : The rabbits in group I and II showed a significant decrease in blood flow in V15 following PDT, but not in group III.We found a significant difference in the grade of thrombus between V5 and V15 in group I and II, and between V10 and V15 in group II.There was a significant difference in the grade of venous dilation (congestion) in V15 between group I and III (p < 0.05, Kruskal-Wallis test). Conclusions : Although further investigation is necessary to evaluate the safety and potential efficacy of phototherapy for esophageal varices, endoscopic PDT may improve outcomes beyond those achieved by any therapy alone (e.g., sclerotherapy or band ligation).