Morphology of the obliteration of an experimental сerebrospinal fluid fistula after laser irradiation of its walls

Abstract

The researchers created an experimental model of a chronic granulating liquor fistula in rats. 90 animals with CSF fistulas were divided into 2 groups: main and control with 45 animals each. In the main group fistula walls were exposed to high-level laser light (laser device «IRE-Polus», wavelength 970 nm, lightguide diameter 0.4 mm, power 0.7W, exposure 5 seconds). The obliteration process in fistulas was assessed in dynamics within one month using standard morphological techniques with morphometry. Experimental animals were examined immediately after the catheter removal and in 1, 3, 7, 14, 21, 30 days. The lumen of fistulas was closed in 14 days in the main group after laser irradiation and in 21 days in the controls. More rapid healing in the main group is explained by the reduced component of hemorrhagic inflammation and less cell infiltration in fistula walls as well as by more intensive increase in fibroblast level and collagen fibers what had been seen since the 7th day. The researchers also observed more rapid maturation of granulation tissue in the fistula area. One month later, a significant increase of micro vascular area in specimens was found in the experimental group, indicating a better formation of vessels in the microcirculatory flow, as compared to the controls.