Charles Bonnet Syndrome: A Review of the Literature

Charles Bonnet syndrome (CBS) commonly occurs in older adults with visual impairments, particularly those with age-related macular degeneration. It is characterized by complex visual hallucinations in individuals without mental disorders. The authors explore diagnostic criteria, demographic characteristics, clinical features, theories of pathogenesis, and management options for people who are diagnosed with CBS. A substantial number of older adults without mental disorders but with age-related visual impairments experience formed visual hallucinations that are due to a condition known as Charles Bonnet syndrome (CBS; Teunisse et al., 1999). CBS is particularly common in people with agerelated macular degeneration (AMD) (Kahn, Shahid, Thurlby, Yates, & Moore, 2008; Lannon et al., 2006) and has been reported in persons with diabetic retinopathy (Holroyd, Rabins, Finkelstein, & Lavrisha, 1994; Teunisse, Cruysberg, Verbeek, & Zitman, 1995; Teunisse, Zitman, Cruysberg, Hoefnagels, & Verbeek, 1996), glaucoma (Nesher, Nesher, Epstein, & Assia, 2001), and cataract (Teunisse, Zitman, & Raes, 1994; Teunisse et al., 1995). Historically, visual hallucinations have been associated with the negative stigma of mental disorders. Menon, Rahman, Menon, and Dutton (2003) stated that individuals who grasp the unreality of the visual hallucinations may be disturbed by the possibility of imminent insanity, and because of their fears, they may be reluctant to discuss their experiences with physicians or allied professionals. It is important for clinicians and those in allied professions to be knowledgeable about CBS in order to avoid misdiagnoses and consequent unsuitable therapies or recommendations. It has been suggested that informing a client that the hallucinations are not a result of mental illness may have a therapeutic effect (Lannon et al., 2006; Menon et al., 2003; Nadarajah, 1998).