The Prevalence and Clinical Characteristics of Charles Bonnet Syndrome in the Republic of Korea

Purpose: To report the clinical characteristics and prevalence of Charles Bonnet syndrome (CBS) in patients with retinal diseases in the Republic of Korea. Methods: Patients with deterioration of visual acuity or visual field or episodes of complex visual hallucination (cVH) with retinal diseases between March 2019 and June 2019 at the retinal outpatient clinic of the Chonbuk National University Hospital were selected to answer standardized questions to determine whether they had symptoms of CBS. Results: The selected 303 patients from the total of 2,916 patients were comprised of 163 males (53.8%) and 140 females (46.2%). The mean age of the patients was 66.0 +/- 15.1 years. six patients (2.4%) of 245 with no response to initial question in 301 with best-corrected visual acuity less than finger counting and two patients with experience of cVH were diagnosed with CBS. Most patients had seen a wide variety of hallucinations, including objects, people, and scenery, with negative emotions, for > 1 year. The hallucinations were experienced daily with the same frequency. Negative feelings such as fear and worry improved when they received appropriate patient education about the hallucinations. Conclusions: The prevalence of CBS in the Republic of Korea is higher than previously reported. We found that relatively young patients with visual impairment could experience cVH from CBS. CBS patients experienced negative emotions for long periods due to the hallucinations which decreased their quality of life. CBS should be considered during the differential diagnosis of cVH in patients with visual impairment due to ophthalmic diseases. We should also provide appropriate patient education to assist them in understanding more fully the clinical characteristics of CBS.