光动力疗法对兔正常声带损伤的影响

Experimental study on the impact of photodynamic therapy on the normal vocal cord injury

目的研究光动力疗法（photodynamictherapy，PDT）中不同光敏剂浓度和不同光照剂量对兔正常声带的反应性特点及损伤修复的影响，为光动力疗法在临床上治疗慢性声带炎症（chronicinflammationofthevocalcords）及癌前病变（precancerouslesions）做前期研究。方法将25只普通级日本大耳白兔按随机数字表法均分为5组，低功率低浓度组A[100mw，10％盐酸氨酮戊酸溶液（aminolevulinicacidhydrochloride，5-AIA）]、高功率低浓度组B（200mW，10％5-ALA）、高功率高浓度组C（200mW，20％5-ALA）、低功率高浓度组D（100mW，20％5-ALA）及正常对照组E（自然光，等渗盐水），5组分别在干预后1d、3d、7d、14d、28d观察比较组织损伤及损伤修复情况。结果光镜下A、B、C、D组出现不同程度的黏膜炎症反应，A组反应较轻，C组反应最重，B、D介于A、C之间，A、B、C、D组第1天出现上皮细胞脱落，3d出现成纤维细胞增生，声带固有层中胶原纤维、透明质酸、纤维连接蛋白含量出现升高，第7天含量最高，与正常对照组比较差异有统计学意义（P〈0．05），28d声带固有层各成分含量趋于正常稍高水平，排列与正常对照组类似，电镜下PDT干预后28d，A、B、C、D组声带基本修复。结论兔声带在一定浓度（10％～20％）的5-ALA和光照功率范围（100～200mW）内，浓度越大，功率越高，损伤越严重，这种损伤基本上可逆的。经过PDT干预后出现可恢复的损伤修复的过程，兔声带于第7天开始出现修复，28d基本修复。

Objective To investigate the reactive characteristics of normal vocal cord tissues to photodynamic therapy （PDT） and the damage effects of different concentration of photosensitizer and different light on normal rabbit vocal cord. Making the preliminary research of PDT in clinical treatment of chronic inflammation of the vocal cords and precancerous lesions. Methods Twenty-five healthy Japanese big ear experimental rabbits were randomly divided into 5 groups： low work rate low dose group A（ 100 roW, 10%5-ALA ）, high work rate low dose group B（200 mW,10%5-ALA）, high work rate high dose group C （ 200 mW ,20% 5-ALA ）, low work rate high dose group D（ 100 mW ,20% 5-ALA） and normal control group E. The issue damage and wound recovery were observed in 1 d, 3 d, 7 d, 14 d, 28 d after intervention. Results A severe inflammation reaction was observed in group A, B, C, D after intervened with PDT compared to normal group. The reaction of group A was lighter, and the reaction of group C was the most serious. The content of collagenous fiber, hyaluronic acid and fibronectin in vocal fold lamina layer was significantly higher than that in normal group （P 〈 0. 05 ）. Different degrees of fiber proliferation were observed in all groups. The content of each component of vocal fold lamina layer tended to be normal slightly higher level in 28 d. Observation by electron microscope showed that there were no significant differences in A, B, C, D, E in 28 d after intervention. Conclusion Recoverable damage repair process can be detected in rabbit vocal after intervened with PDT, which began in 7 d and basically completed in 28 d. In a certain concentration （10% -20% ） and dose range （100 -200 mW）. The higher of photodynamic dose, the more serious of the damage. And the damage was basically reversible.