A STUDY ON LASER-INDUCED AUTOFLUORESCENCE FROM COLONIC CARCINOMA

已有研究表明，激光照射能够诱导组织的自体荧光。点组织荧光被用来区分正常粘膜和结肠腺瘤。然而，荧光物质在组织中的定位还不一定确定，这使得对荧光光谱变化的解释变得模糊。本研究的目的是确定诱导荧光的组织来源，并确定在结肠腺瘤组织中发生荧光衰减的原因。为此，对34例腺瘤和10例正常粘膜进行了325 nm激光荧光分析。正常粘膜表面的荧光光谱的峰值波长为450 nm。而来自粘膜肌层或粘膜下层的荧光光谱在380和440 nm处有双峰。连续激光照射10s，450 nm处的峰值强度不降低，而380或440 nm处的峰值强度在10s时衰减到初始强度的70%以下。这些发现表明，这三种荧光成分归因于特定结肠层中的三种不同的荧光粉。腺瘤表面的荧光光谱也在450 nm处有相同的峰值波长。而峰值强度减弱到正常粘膜的1/2以下。峰值强度与发育不良粘膜的大体形态或粘膜厚度无关。此外，粘膜下层的荧光对观察到的荧光没有影响。腺瘤表面的峰值强度减弱可能是由于与正常粘膜相比固有层内的荧光物质减少所致。

It has been shown that laser irradiation is able to induce autofluorescence from tissues. Point tissue fluorescence has been investigated to distinguish normal mucosa from colonic adenoma. While, the localization of fluorescent materials in the tissue has not been necessarily established, which made the interpretation of changes in fluorescence spectra obscure. The aim of this study was to determine the histological origin of induced fluorescence and to determine the cause of fluorescence attenuation occurring in the tissue of colonic adenoma. For this purpose, 325 nm-laser fluorimetry was performed by using 34 adenomas and 10 normal mucosa. Fluorescence spectrum form the normal mucosal surface exhibited a peak wave length at 450 nm. While, fluorescence spectrum form the muscularis mucosae or submucosa had biphasic peak length at 380 and 440 nm. A peak intensity at 450 nm was not reduced by a continuous laser irradiation of 10 sec, while those at 380 or 440 nm decayed to less than 70 % of the initial intensities by irradiation of 10 sec. These findings suggest that the three orescence components are attributed to three different phosphors in specific colonic layer. Fluorescence spectra from the surface of adenoma had also the same peak wave length at 450 nm. While, peak intensity was attenuated to less than 1/2 of that from the normal mucosa. The peak intensity was found to be not correlated with gross morphology of dysplastic mucosa, or the mucosal thickness. Furthermore, the fluorescence in the submucosa did not influence on the observed fluorescence. The attenuated peak intensity from the surface of adenoma may be attributed to reduced fluorescent material in the lamina propria compared with the normal mucosa.