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Complex visual hallucinations (Charles Bonnet syndrome) in the hemianopic visual field following occipital infarction

Pammal T Ashwin1, Marie D Tsaloumas

  • 1Department of Ophthalmology, University Hospitals Birmingham, Raddlebarn Road, Selly Oak, Birmingham, B29 6JD United Kingdom. pammal.ashwin@gmail.com

Journal of the Neurological Sciences
|June 26, 2007
PubMed

Insights

Charles Bonnet syndrome causes visual hallucinations in older adults with vision loss. A rare variant presents in a hemianopic field with intact vision, highlighting the syndrome's diverse manifestations.

Area of Science:

  • Neuroscience
  • Ophthalmology
  • Geriatrics

Background:

  • Charles Bonnet syndrome involves visual hallucinations in individuals with vision impairment.
  • It is crucial to differentiate it from psychiatric disorders in the elderly.
  • Hallucinations typically occur with significant vision loss or occipital cortex disruption.

Purpose of the Study:

  • To describe a rare variant of Charles Bonnet syndrome.
  • To detail hallucinations in a hemianopic visual field with preserved visual acuity.
  • To explore the etiology, treatment, and variations of this phenomenon.

Main Methods:

  • Case report of a patient with an occipital infarct presenting with hemianopic visual hallucinations.
  • Review of existing literature on Charles Bonnet syndrome variants.
  • Analysis of the patient's clinical presentation and visual field deficits.

Main Results:

  • The patient experienced complex visual hallucinations exclusively within their hemianopic visual field.
  • Visual acuity remained largely unimpaired.
  • This case challenges previous understandings of the syndrome's typical presentation.

Conclusions:

  • This rare variant expands the known spectrum of Charles Bonnet syndrome.
  • Increased awareness among healthcare practitioners is needed due to its potential underdiagnosis.
  • Patients' reluctance to report symptoms due to psychiatric concerns is a significant barrier.

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