A new animal model for monitoring the early cerebral vasospasm after subarachnoid haemorrhage.

AIM: Spasm of cerebral arteries is a complication associated with subarachnoid haemorrhage. The aim of the present work is to find an experimental model of reliable, simple and in vivo monitoring of ''early'' basilar artery spasm after subarachnoid haemorrhage (SAH). Early spasm occurs within minutes of the SAH, its duration is approximately 1 hour. The need of different morphological and haemodynamic methods to evaluate experimental early spasm is reported.

METHODS

To overcome intracranial surgical manipulations and biological of contrast and fixation media we designed a model that allows in vivo functional monitoring of basilar blood flow far away from the spasm without direct surgical and chemical interferences. Seventeen adult Burgundy rabbits were studied.

RESULTS

Under homeostatic monitoring ''on-line'' carotid blood flow (carotid BF) .changes produced by SAH in cisterna magna of 12 (plus 5 sham treated) animals were studied from the common carotid artery after external carotid artery occlusion before, during SAH up to the end of the experiments. All the animals underwent digital subtraction cerebral panangiography (CPA) after SAH obtaining a significant increase of carotid BF only when basilar vasospasm was shown by CPA.

CONCLUSIONS

Carotid BF increase during basilar vasospasm was defined ''functional. monitoring'' of early spasm.