We studied the clinical and histopathological changes in twenty-seven cases of acute ischemic stroke, aged between 65 and 75 years. All deaths occurred within 30 days after stroke. The aim of our study was to establish the clinical and histological correlations in acute ischemic stroke to detect prognostic factors. Brain lesions after acute stroke were observed in all regions. Our study describes the heterogeneity of brain injury after acute ischemic stroke with the participation of all brain components and the chronology in which these lesions develop and evolve. By histological and immunohistochemical studies, we identified neuronal, glial and vascular damage. The neurons had undergone in the area of lesion a process of necrosis, ballooning or condensation process. In the ischemic penumbra, we observed the presence of red neurons. Vascular lesions were represented by the discontinuity of capillaries, always associated with a marked perivascular edema. The following clinical and morphological correlations were established: liquefactive necrosis, astrocyte gliosis, phagocytosis phenomena are the more intense the later the death of the patient; apoptosis phenomena are the more intense the faster the death of the patient; the entire cerebral microcirculation presented microscopic modifications following the ischemic strokes, regardless of the time since the lesion occurred and the histological examination was made; the major neurological complications of the ischemic stroke - the hemorrhagic transformation phenomena, cerebral edema, were microscopically objectified, regardless of the time since the lesion occurred and the histological examination was made.