The potential role of myofibroblasts in the obliteration of arteriovenous malformations after radiosurgery

摘要: Objectives To examine the structural changes in arteriovenous malformations (AVMs) after stereotactic radiosurgery and to identify cytoskeletal antigen phenotype of proliferating cells gain information about possible mechanism obliteration. Methods We conducted immunohistochemical electromicroscopic investigations surgical material that was removed from seven patients. The patients were harboring cerebral AVMs had been previously treated with gamma knife irradiation, they experienced subsequent bleeding 10 52 months treatment. Results Light microscopy revealed spindle-shaped cell proliferation connective tissue stroma subendothelial region vessels. ultrastructural characteristics these spindle identical those designated as myofibroblasts wound healing processes pathological fibromatoses. Whereas nonirradiated specimens AVMs, similar expressed vimentin desmin positivity, irradiated cases, alpha-smooth muscle actin activity also observed. Conclusion In view contractile myofibroblasts, generated by irradiation transformation resting into an activated form could be relevant shrinking process eventual occlusion radiosurgery.