Histopathological study of vascular changes after intra-arterial and intravenous injection of N-butyl-2-cyanoacrylate.

OBJECTIVE: To assess the histopathological vascular changes after injection of N-butyl-2-cyanoacrylate into the vessels of adult rabbits.
METHODS: The animals used were 42 pure-blood New Zealand white rabbits weighing 2-3 kg. 0.2 mL cyanoacrylate with lipiodol was injected into the external jugular vein and femoral artery of each rabbit. Tissue specimens were obtained for histopathological study at 3 days, 7 days, 2 weeks, 3 weeks, 4 weeks, 2 months and 3 months after injection.
RESULTS: The vessels were obliterated immediately after the injection. The main manifestation of histopathology at 3 days to 2 weeks was an acute inflammatory reaction; this progressed to subacute vasculitis at 3 weeks and a chronic granulomatous foreign body reaction developed at 4 weeks. The glue mass essentially disappeared in 2-3 months, replaced by fibrotic tissue with partial vascular recanalization. At 3 weeks after injection, the elastic fibrils of the arterial wall proliferated distinctly, resulting in narrowing of the lumen with subsequent obliteration, whereas the venous wall still showed inflammation and necrosis without hyperplasia of elastic fibrils. Extrusion of glue was observed over 1-3 months in both arteries and veins and was obvious in the latter.
CONCLUSIONS: The histopathological changes after injection of N-butyl-2-cyanoacrylate were similar in the arteries and the veins with the exception of hyperplasia of elastic fibrils in the arterial wall and inflammation and necrosis in the venous wall at 2-3 weeks. Glue extrusion was seen in both arteries and veins.