Clinical Characteristics of the Charles Bonnet Syndrome in Patients with Neovascular Age-Related Macular Degeneration: The Importance of Early Detection

Abstract

We investigated the characteristics, prognosis, and clinical outcome of the Charles Bonnet syndrome (CBS) in patients with neovascular age-related macular degeneration (AMD). Methods: Five hundred psychiatrically healthy patients with neovascular AMD were screened for CBS. The individuals that fulfilled the inclusion criteria were systematically interviewed using a structured questionnaire that covered the impact, prognosis, risk factors, phenomenology, symptoms, and knowledge about the syndrome. A control group of 45 patients was used for comparison. Demographic data, current medication, and ocular risk factors were collected in all patients. Results: Forty-five patients with CBS were identified. The majority of patients reported images that consisted of colored (62%) animals (44%) or faces (42%) that lasted for seconds (53%). Most patients reported a selflimited disease with a median duration of symptoms between 9 and 11.5 months, with only 7% knowing about CBS at symptom onset. The degree of visual deficit did not predict the characteristics, complexity, frequency, duration, or impact of visual hallucinations. One-third of patients reported negative outcome, which was associated with shorter duration of CBS (p = 0.023), fear-inducing images (p < 0.001), and impact on daily activities (p = 0.015). Conclusion: The prevalence of CBS in neovascular AMD patients is high and clinically relevant. Patients with recent onset of visual hallucinations and describing fear-inducing images are at greater risk for negative outcome. Periodic screening may minimize the negative consequences of this disease.

Impact of Charles Bonnet Syndrome on visually impaired older adults’ ability to engage in physical activity: A scoping review

“…One case report found that CBS did not interfere with daily function, reflecting findings in other studies -not everyone experiences difficulties linked to visual hallucinations (Cox & Ffytche, 2014;Esteves Leandro et al, 2020). As the purpose of medical case reports is to detail the diagnostic process, in-depth exploration about how CBS effects everyday function is not a priority, or may not be reported.…”

“…Esteves Leandro et al (2020) also looked at the clinical impact of CBS, focusing on patients with neovascular age-related macular degeneration. Out of 500 eligible patients attending an eye clinic, 45 screened positive for CBS and completed a structured, face-to-face questionnaire based on Cox and Ffytche’s (2014) survey items.…”

“…As ‘moving about’ was not analysed as a discrete entity, it is not possible to identify an association between CBS and mobility difficulties via existing studies. Cox and Ffytche (2014) and Esteves Leandro et al (2020) grouped mobility and other comparatively sedentary activities such as watching TV, under the over-arching category ‘abilities’: a significant association between one or more daily abilities affected by CBS and negative outcome CBS was found. Scott et al (2001) used the composite CDS score incorporating ADLs, IADLs, and mobility subscales to measure functional status.…”

“…CBS affects some people with sight loss, causing spontaneous external visual hallucinations (Ffytche et al, 1998) that the individual realises are unreal, although initially, contextually relevant percepts may be difficult to differentiate from reality (Menon, 2005). The nature of CBS varies from person to person: visual hallucinations are typically complex (people, distorted faces, animals, and whole scenes) (Hamedani & Pelak, 2019), static or dynamic (Schultz & Melzack, 1991), and can last for seconds or present continuously (Esteves Leandro et al, 2020). Duration from symptom onset varies, but a large-scale survey found that three quarters of respondents with CBS had experienced visual hallucinations for 5 years or longer (Cox & Ffytche, 2014).…”

Prevalence of Charles Bonnet syndrome in patients with glaucoma: a systematic review with meta‐analyses

“…Generally, awareness of CBS among patients is limited (Singh et al 2014). When the patient is unaware of the nature of CBS, these phenomena may induce fear and anxiety (Esteves Leandro et al, 2020). It may further complicate the issue, that these experiences may be difficult to talk about given the taboo and difficulties concerning having a psychiatric disease or dementia.…”