The Present State of Charles Bonnet Syndrome

Abstract

Abstract: This review attempts to integrate the present, somewhat confusing, state of the research on Charles Bonnet syndrome (CBS). After a brief introduction giving the history of CBS and its diagnostic criteria, relevant case reports and studies are reviewed. As a result of this review, it is revealed that CBS may have heterogenous causes: peripheral (visual impairment), central (organic brain lesion), and both. The neuroimaging findings on CBS are inconsistent, but in the pharmacotherapy for CBS, it has been found that anticonvulsants may be effective, although randomized controlled studies are needed. Moreover, the time course of CBS seems to vary: remission, continuation, development into dementia, and so on. With respect to a possible association between CBS and dementia, it is suggested that clinicians follow such patients up longitudinally, because the available diagnostic criteria for CBS are almost exclusively based on cross‐sectional observations.