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

György T. Szeifert, Andras A. Kemeny, Walter R. Timperley, David M.C. Forster

Research output: Contribution to journalArticle

59 Citations (Scopus)


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

Original languageEnglish
Pages (from-to)61-66
Number of pages6
Issue number1
Publication statusPublished - Jan 1 1997



  • Arteriovenous malformations
  • Gamma knife
  • Immunohistochemistry
  • Myofibroblast
  • Stereotactic radiosurgery

ASJC Scopus subject areas

  • Surgery
  • Clinical Neurology

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