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Published on: April 11, 2025
Visual hallucinations during visual recovery after central retinal artery occlusion
Colin S H Tan1, Bernhard A Sabel, Kong-Yong Goh
1Eye Institute at Tan Tock Seng Hospital, National Healthcare Group, 11 Jalan Tan Tock Seng, Singapore 308433. colintan_eye@yahoo.com.sg
Archives of Neurology
|April 12, 2006
Summary
Charles Bonnet syndrome, causing visual hallucinations, was observed in two patients following central retinal artery occlusion. These hallucinations occurred during partial visual recovery, suggesting a link to brain plasticity.
Area of Science:
- Ophthalmology
- Neuroscience
- Visual Science
Background:
- Charles Bonnet syndrome involves complex visual hallucinations in individuals without psychiatric conditions.
- This syndrome has not been previously documented following central retinal artery occlusion.
Observation:
- Two patients experienced sudden, severe vision loss due to central retinal artery occlusion.
- Formed visual hallucinations, characteristic of Charles Bonnet syndrome, emerged days after vision loss.
Findings:
- Hallucinations occurred within and at the edges of remaining visual fields.
- The visual hallucinations coincided with periods of partial visual recovery and visual field expansion.
- Both visual recovery and hallucinations resolved concurrently.
Implications:
- The study suggests deafferentation as a cause for these hallucinations.
- The findings indicate that Charles Bonnet syndrome during visual recovery may reflect visual system plasticity.
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