The prevalence and clinical characteristics of Charles Bonnet Syndrome in Danish patients with neovascular age‐related macular degeneration

Abstract

To investigate the prevalence and clinical characteristics of the Charles Bonnet Syndrome (CBS) in a group of Danish patients with neovascular age-related macular degeneration (AMD) and to study whether CBS is associated with a specific retinal morphology. Three-hundred consecutive patients with neovascular AMD attending assessment consultations following variable series of ranibizumab therapy were actively asked whether they had symptoms of CBS. If they responded positively, a detailed questionnaire was orally administered to inquire into the details of the symptoms. Detailed optical coherence tomography and autofluorescence was performed. A comparison was made between retinal morphology of a randomly selected equal number of patients without CBS to patients with CBS. Twenty-five (8.3%) patients of 300 had hallucinations attributable to CBS. The median lesion size - measured as total area with increased autofluorescence - in the CBS group (median 14.2 mm(2)) was not significantly different from the non-CBS group (median 16.2 mm(2)); however, the patients with CBS had significantly larger areas of geographic atrophy (median 2 mm(2)) compared to patients without CBS (median 0.3 mm(2)) (p = 0.002). CBS is not uncommon in an unselected population with neovascular AMD, and symptoms of CBS may be associated with larger areas of geographic atrophy.