What is the best plan of care for an elderly patient with Charles Bonnet syndrome (CBS) experiencing visual hallucinations?

Management of Charles Bonnet Syndrome in Elderly Patients

The cornerstone of managing Charles Bonnet syndrome is patient and family education with reassurance, as this alone often provides significant relief and decreased anxiety without requiring pharmacological intervention. 1

Initial Assessment and Diagnosis Confirmation

Before implementing treatment, confirm the diagnosis by verifying the four characteristic features of CBS 1:

• Recurrent, vivid visual hallucinations in the context of vision impairment 1
• Preserved insight that the images are not real 1, 2
• Absence of other neurological or medical explanations for the hallucinations 1
• Some degree of vision loss (can be reduced acuity, contrast sensitivity, or visual field loss, including monocular loss) 1

Red flags requiring alternative diagnosis consideration include lack of insight despite CBS education, hallucinations that interact with the patient, or accompanying neurological signs 1, 2. These atypical features should prompt comprehensive neurological evaluation with brain MRI and consideration of conditions like dementia with Lewy bodies, Parkinson's disease, or primary psychiatric disorders 3.

First-Line Management: Education and Non-Pharmacological Strategies

Education is therapeutic in itself 1. The American Academy of Ophthalmology emphasizes that discussion with patients and caregivers about the benign nature of CBS hallucinations leads to significant relief 1. Explain that these phantom visions result from cortical-release phenomena due to lack of visual input, affecting 15-60% of visually impaired patients depending on the population studied 1.

Self-management techniques that may reduce hallucinations include 1:

• Eye movements
• Changing lighting conditions
• Distraction techniques

These methods have limited evidence from case series but can be recommended as they are safe and may provide benefit 1.

Vision Rehabilitation Referral

Refer patients to vision rehabilitation services to optimize remaining vision and address psychological aspects 1. The American Academy of Ophthalmology provides moderate-quality evidence that psychological therapies and support groups benefit vision-related quality of life and depression in visually impaired patients 1.

Vision rehabilitation should address 1:

• Maximizing remaining vision through lighting modifications, magnification, and contrast enhancement
• Preventing social isolation and depression
• Providing peer support groups where patients can discuss their experiences

Pharmacological Intervention: When and What to Use

Pharmacological treatment is NOT first-line and should be reserved for patients with severe distress despite education and non-pharmacological measures 1, 4. Currently, there is no significant evidence of efficacy for any pharmacological agent in typical CBS 1.

If medication is considered necessary, the evidence is limited to case reports 1:

• Donepezil may be considered, particularly if cognitive decline emerges, as one case report showed improvement in both hallucinations and cognitive function in a patient developing dementia 5, 6
• Donepezil has fewer adverse effects than anticonvulsants or antipsychotics, making it a safer option for elderly patients 6
• Avoid antipsychotics unless there is loss of insight or development of true psychotic features, as these represent atypical CBS or alternative diagnoses 7

Monitoring for Complications

Screen for depression and anxiety at follow-up visits, as vision loss significantly increases risk of mental health deterioration 1. Professional psychiatric assessment should be recommended for patients reporting severe mood changes, interference with daily life, or suicidal ideation 1.

Monitor for loss of insight, which suggests progression to dementia or development of a primary psychiatric disorder rather than typical CBS 5, 7. This requires reassessment of the diagnosis and consideration of alternative or comorbid conditions.

Common Pitfalls to Avoid

• Do not prescribe antipsychotics reflexively for CBS hallucinations, as typical CBS patients maintain insight and the hallucinations are benign 1, 4
• Do not overlook medication-induced causes such as anticholinergics, steroids, or dopaminergic agents that may contribute to hallucinations 3
• Do not miss treatable ophthalmologic conditions like cataracts that, when corrected, may reduce hallucinations 4
• Do not dismiss the psychological impact of vision loss itself, which requires addressing through rehabilitation and support services 1