Yu.A. Medvedev, B.M. Nikiforov, Zh.Z. Zakaryavichus, V.P. Bersnev, Yu.M. Zabrodskaya
(Polenov Research Neurosurgical Institute, Saint Petersburg)
There were 30 cases, who died during the 2nd-4th weeks after ruptures of cerebral bifurcation aneurysms. The material (arteries) was taken from a zone of spasm, diagnosed with the help of angiography, when they had been alive.
Conventional methods of examination (optic and electron microscopy) were used.
It was found out, that during a period, characterized by absence of dilatation therapy effects, smooth-muscle cells of segments of Willis circle arteries had been in a parabiotic state (dystrophy) or dead (necrosis). The greatest changes were typical of a contraction apparatus of muscular cells (thin and thick myofibrils). It was either subject to irreversible changes or perished with formation of peculiar "onion" ball-like structures, seen in semi-thin sections even in light microscopy. A degenerative-necrotic process was caused by a superdurable irreversible spasm-contracture.