Aim. An analysis of 233 cases of unreal visual perceptions reported in the literature (except for 13 cases). Unreal visual perceptions, usually called hallucinations, according to the literature more frequent in females and in the elderly, are associated with visual impairment and brain dysfunction, especially of the visual tract, diencephalon (thalamus), and the brain stem. Prognosis is considered to be uncertain.
Methods. In the analysis of233 cases of visual hallucinations and parahallucinations reported mostly in the English-language publications in the years 1976-2004, the nature of these patients' organic changes and mental disorders, characteristics and type of their visual perceptions, as well as treatment methods and their efficacy were taken into account.
Results. Five groups of unreal visual perceptions can be distinguished: these related to diseases of the central nervous system, the Charles Bonnet syndrome, to mental disorders, and either drug-induced or associated with an ophthalmic surgery. In all the analysed groups females and individuals with some visual impairment predominated. A third of these patients were aged under 65 years. Brain lesions were situated in both hemispheres, thalamus, visual tract. Good results of treatment were attained in almost 80% ofpatients.
Conclusions. Only in some cases visual perceptions could be recognised as hallucinations due to the patients' lack of insight into their unreal nature. In almost half of cases the presence of insight indicated that such perceptions were parahallucinations (hallucinoids), or sensory automatisms. In the group ofpatients without diseases of the central nervous system neuroleptics were substantially more effective than other treatment methods. In the group with diseases of the CNS there was no such relationship.