Immunohistochemical analysis of a cerebral arteriovenous malformation obliterated by radiosurgery and presenting with re-bleeding. Case report.
The purpose of this study was to analyze immunohistochemical characteristics of the cell population in a radiosurgically obliterated cerebral arteriovenous malformation (AVM) after recurrent hemorrhage. Immunohistochemical reactions were carried out on paraffin-embedded histological sections for von Willebrand factor (FVIII), CD34 endothelial antigen (CD34), vimentin and alpha-smooth-muscle actin (SMA) cytoskeletal proteins. Histopathological analysis revealed that the majority of AVM channels were replaced by hypocellular scar tissue. However some of them still disclosed thrombus organization by granulation tissue seven years after radiosurgery. FVIII and CD34 reactions revealed vessel neoformation in thromboses. Proliferating spindle-shaped cells with SMA and vimentin expression were identified in the granulation tissue. These histopathological findings suggest the role of re-canalization in recurrence of hemorrhage following radiosurgical obliteration of the AVM. Contribution of myofibroblastic elements in the vessels' occlusion after radiosurgery is also demonstrated.
Centre Gamma Knife, Université Libre de Bruxelles, Hôpital Académique Erasme, Brussels, Belgium.
György T
GT
Szeifert
Isabelle
I
Salmon
Danielle
D
Balèriaux
Jacques
J
Brotchi
Marc
M
Levivier
D000328:Adult; D002543:Cerebral Hemorrhage / Q000175:diagnosis / Q000503:physiopathology* / Q000517:prevention & control / Q000601:surgery*; D003937:Diagnosis, Differential; D006801:Humans; D007150:Immunohistochemistry; D002538:Intracranial Arteriovenous Malformations / Q000175:diagnosis / Q000503:physiopathology* / Q000601:surgery*; D008297:Male; D016634:Radiosurgery / Q000379:methods*; D055502:Secondary Prevention