Pathological changes in experimental saccular aneurysms in the carotid artery of the rat.

Although the reason for development of saccular aneurysms in humans has still not been elucidated, the process might be observed and explained using a reproducible aneurysm model in vivo. In this paper, a sequential pathological study of the experimental saccular aneurysms was made. No additional influential factors were applied. At all stages of the development between the induction and 6 months, the histology of the aneurysm wall was similar to that of human aneurysms. The imbalance of the degeneration and regeneration processes during the development of these experimental aneurysms is discussed according to the pathological findings in different periods. Haemodynamic stress and different regenerative speeds in different arterial tissues must be responsible for the saccular aneurysm formation and growth.