Statistics from Altmetric.com
A blind, otherwise healthy female (50 years old) was referred to our hospital with visual complaints concerning ongoing sensations of colour and movement. She had suffered from bilateral eye disease (retinopathy), resulting in irreversible blindness 22 years ago. Ever since, she perceived visual sensations in the entire visual field, consisting of changing colours and a semitransparent flow. The movement sensations showed a regular cyclic pattern: changing direction every 2 days, being slow when directed to the right and fast when directed to the left. In particular, the first day with flow to the left was very disturbing. One year after the start of the visual sensations, both eyes were removed and replaced by prostheses, which of course had no effect on the visual sensations. Antiepileptic and antipsychotic drugs had no effect either. An equivalent of Charles Bonnet syndrome is suggested.1
F18-fluorodeoxyglucose positron emission tomography and functional magnetic resonance imaging
F18-fluorodeoxyglucose positron emission tomography (FDG-PET) and functional magnetic resonance imaging (fMRI) were performed to gain a further insight in mechanisms underlying these visual sensations and to define a possible focus for therapeutic rTMS. Cerebral FDG-PET showed bilaterally reduced occipital-, superior parietal and thalamic metabolism (figure 1A). Using fMRI, we localised brain regions specifically involved in either visual motion or colour perception, by verbally instructing the patient to focus attention to either colour or movement. In a …
If you wish to reuse any or all of this article please use the link below which will take you to the Copyright Clearance Center’s RightsLink service. You will be able to get a quick price and instant permission to reuse the content in many different ways.