[Chiasmal syndromes (author's transl)].
Klíčová slova
Abstraktní
Chiasmal syndromes (characterized by bitemporal field defects, decrease of vision and simple optic atrophy) are not only caused by tumors within the chiasmal region, but also occur in inflammatory, toxic, demyelinizing and hereditary-atrophic processes of the chiasm, respectively the optic nerve. In the presence of classic bitemporal visual field defects the probability of a tumor within the sellar region is very great. Apart from the most frequent pituitary adenoma one has to consider the craniopharyngioma, the meningioma of the tuberculum sellae, the olfactory meningioma and the meningioma of the sphenoid wing. The specific symptomatology of these sellar, supra- or parasellar tumors is discussed. In the presence of atypical or incipient bitemporal visual field defects, as they occur also in the early stages of tumors of the chiasmal region, one has first of all to exclude all other possible causes for such field defects such as refraction scotomas, tobacco-alcohol-amblyopias, dominant hereditary optic atrophies, the uni- or bilateral optic neuritis and the intoxications of the optic nerves. In the differential diagnosis of tumors of the sellar region one has to consider infra- and supraclinoidal aneurysms, tumors of the chiasm (gliomas of the chiasm), the distant effect of a hydrocephalus of the IIIrd ventricle on the chiasm and the optochiasmatic arachnoiditis.