On the posterior infarct

Abstract

The article deals with infarctions in the territory of the posterior cerebral arteries. For a better understanding of pathoanatomical and pathogenetical factors influencing posterior cerebral infarctions embryological, orthological and pathological data on the posterior cerebral artery and on its leptomeningeal anastomoses to other cerebral arteries were reported in the first two chapters. Chapter 3 includes a review of findings on the predilection sites for occlusions of the posterior cerebral artery, on the relative incidence and also on pathogenetical factors of posterior cerebral infarctions. The few papers especially dealing with the posterior cerebral infarctions in the CCT were indicated likewise. Chapter 4 contains our own findings on 180 patients with posterior cerebral infarctions, who were all examined with CCT (the slices were done parallel to the fronto-occipital line); data on age, sex and hemispheric distribution of the sample and on combinations with other cerebral infarctions were reported. 159 posterior cerebral infarctions (of 144 patients including 15 with bilateral infarctions) could be described "anatomically". As to the maximum infarction areas referred to 8 defined slice levels, differences to the findings reported so far in the literature were observed; they comprise the (ventro-) lateral borders of the infarction areas including the longitudinal fibre projections (e.g. the optic radiation), the cranial extension of the posterior cerebral infarctions and the splenial as well as thalamic lesions. The posterior cerebral infarctions were classified as uni-territorial, bi-territorial and subtotal subtypes. Among the uni-territorial posterior cerebral infarctions calcarine infarctions outweighed those in the territory of the posterior temporal (temporo-occipital) artery and of the parieto-occipital artery by a ratio of 2:1:1. The overlap areas of the uni-territorial posterior cerebral infarctions are shown in figures. The second, less frequent bi-territorial subtype is a combination of infarctions in the territories of the calcarine and the parieto-occipital arteries. The calcarine, the medio-basal and the subtotal subtype occurred in about 23% of the "anatomically" evaluated posterior cerebral infarctions. At length, thalamic and splenial infarctions associated with any of the subtypes were observed in about a quarter of all posterior cerebral infarctions. As to the subtotal posterior cerebral infarctions additional thalamic and splenial infarctions can be expected in about 40%.