Understanding the Charles Bonnet syndrome: An updated review

Area of Science:

• Neuroscience
• Ophthalmology
• Psychiatry

Background:

• Charles Bonnet Syndrome (CBS) is underrecognized, affecting visually impaired individuals with preserved cognition.
• It involves complex visual hallucinations, often confusing for patients.
• Existing definitions and diagnostic criteria lack consistency.

Purpose of the Study:

• To review evolving definitions, epidemiology, risk factors, and pathophysiology of CBS.
• To highlight diagnostic inconsistencies and multifactorial origins.
• To explore differential diagnoses and therapeutic strategies.

Main Methods:

• Comprehensive literature review of studies on CBS.
• Analysis of epidemiological data and risk factors.
• Examination of pathophysiological models and therapeutic approaches.

Main Results:

• CBS affects up to 10% of visually impaired individuals, with variable prevalence due to inconsistent definitions.
• Risk factors include visual acuity, sex, social isolation, and medications, though evidence is inconclusive.
• Pathophysiological theories involve sensory deprivation, cortical imbalances, and predictive coding models.

Conclusions:

• CBS requires clearer diagnostic criteria and further research into neurobiological mechanisms.
• Early recognition and patient reassurance improve outcomes, despite the lack of standardized treatment.
• Longitudinal studies are needed to understand CBS prognosis and its link to cognitive decline.