FDG-PET Scanning Shows Distributed Changes in Cortical Activity Associated with Visual Hallucinations in Eye Disease

Endocr Metab Immune Disord Drug Targets. 2019;19(1):84-89. doi: 10.2174/1871530318666180830112709.

Abstract

Background and objective: Charles Bonnet Syndrome (CBS) has been defined as complex visual hallucinations (CVH) due to visual loss. The underlying mechanism of CBS is not clear and the underlying pathophysiology of the visual hallucinations in CBS patients and pure visually impaired patients is still not clear.

Methods: In our study, we have scanned three patients with eye disease and CBS (VH+) and three patients with eye disease without CBS (VH-) using FDG-PET.

Results: Our results showed underactivity in the pons and overactivity in primary right left visual cortex and inferior parietal cortex in VH- patients and underactivity in left Broca, left inf frontal primary visual cortex and anterior and posterior cingulate cortex in VH+ patients relative to the normative 18FFDG PET data that was taken from the database consisting of 50 age-matched healthy adults without neuropsychiatric disorders.

Conclusion: From this distributed pattern of activity changes, we conclude that the generation of visual hallucination in CBS is associated with bottom-up and top-down mechanism rather than the generally accepted visual deafferentation-related hyperexcitability theory.

Keywords: 18F-FDG PET scanning; Visual hallucination; age-related macular degeneration; charles bonnet syndrome; diabetic retinopathy; glaucoma; visual deafferentation theory..

Publication types

  • Case Reports

MeSH terms

  • Aged
  • Cerebral Cortex / diagnostic imaging*
  • Charles Bonnet Syndrome / diagnostic imaging*
  • Diabetes Complications / diagnostic imaging
  • Eye Diseases / complications*
  • Eye Diseases / diagnostic imaging*
  • Female
  • Fluorodeoxyglucose F18
  • Hallucinations / complications*
  • Hallucinations / diagnostic imaging*
  • Humans
  • Male
  • Parietal Lobe / diagnostic imaging
  • Pons / diagnostic imaging
  • Positron-Emission Tomography
  • Radiopharmaceuticals
  • Risk Factors
  • Visual Cortex / diagnostic imaging

Substances

  • Radiopharmaceuticals
  • Fluorodeoxyglucose F18